ph.d thesis

A

RepuMinisAndAl-MuColleDepa

E

Asst.Pro

ublic of IRstry of HScientifiustansir

ege of Scartment o

ffect o

In

Ali M

of Dr. Na

Octob

RAQigher Edc Reseaiyah Uni

cience of Atmos

of Soon U

Depar

An partial

The de

Moham

M.S

Natiq Ahm

ber 2007

ducationrchversity

spheric S

omeUltrav

A Thertment o

ColleAl-Musta fulfillmeegree of

Atmos

mmed AB.Sc

Sc (Atmo

Su

med Zak

7

Sciences

Atmviolet

sis submof Atmosege of S

ansiriyahent of thf doctorspheric S

By Abdulc(Physicsospheric S

upervise

ki Ass

s

ospht Rad

mitted tospheric sScienceh Univerhe requirof philoSciences

lrahmas) 1994 Sciences)

ed by

st.Prof D

Ram

heric diatio

osciences

rsityrementssophy ins

an AL-

s) 2002

Dr. Kais

madan 14

Facton

s

s for n

-Salihi

s Jamil A

428

ors

i

Al-Jumaaily

بسم اهللا الرحمن الرحيمبسم اهللا الرحمن الرحيمهو الذي جعل الشمس ضياء والقمر نورا وقدره منازل هو الذي جعل الشمس ضياء والقمر نورا وقدره منازل

ذلك إال بالحق ذلك إال بالحق اهللاهللالتعلموا عدد السنين والحساب ما خلق لتعلموا عدد السنين والحساب ما خلق يفصل اآليات لقوم يعلمون إن في اختالف الليل والنهار وما يفصل اآليات لقوم يعلمون إن في اختالف الليل والنهار وما

..في السموات واألرض اليات لقوم يتقونفي السموات واألرض اليات لقوم يتقون اهللاهللاخلق خلق

صدق اهللا العظيمصدق اهللا العظيم

))66--55أية أية ( ( يونس يونس ةةسورسور

SUPERVISION CERTIFICATION

We certify that this thesis entitled “Study of Atmospheric parameters Effect on Ultraviolet Radiation transfer” was prepared under our supervision in the Department of Atmospheric sciences, College of Science Al-Mustansiriyah University as a partial fulfillment of the requirements for the degree of Doctor of philosophy in Atmospheric sciences.

Signature Dr. Kais Jamil Al-Jumaily Assist. Professor (Supervisor) Dept of Atmospheric Sciences Date:

Signature Dr. Natiq Ahmed Zaki Assist. Professor(Supervisor) Dept of Atmospheric Sciences Date:

In view of the available recommendation, I forward this thesis for debate by the examination committee.

Signature Dr. Kais Jamil Al-Jumaily Assist. Professor Graduate Studies Coordinator Date:

COMMITTEE CERTIFICATION

We, the members of examining committee certify that after reading the present thesis in titled “Effect of Some Atmospheric Factors on Ultraviolet Radiation” and we have examining the student “Ali Mohammed AbdulRahman Al-Salihi” in its content, and in who connected with it, and that in our opinion it meets the standard of thesis for degree of Doctor of Philosophy in atmospheric science, with excellent degree

Signature Name: Dr. Rasheed H. Al-Naimi Title: Professor Date: (Chairman)

Signature Name: Dr. Hassan H. Salman Title: Professor Date: (Member)

Signature Name: Dr. Nadir Fadil Habobi Title: Professor Date: (Member)

Signature Name: Dr. Husain Zaidan Ali Title: Expert Date: (Member)

Signature Name: Dr. Talib Abd Zaid Title: Senior Researcher Date: (Member)

Signature Name: Dr. Natiq Ahmed Zaki Title: Assistant Professor Date: (Supervisor)

Signature Name: Dr. Kais Jamil Al-Jumaily Title: Assistant Professor Date: (Supervisor)

Approved by the council of the college of science, Al-Mustansiryah University Signature: Dr. Kadhum H. Al-Musawi

Dean of the college of science Date:

AAcckknnoowwlleeddggeemmeennttss

First and foremost I thank ALLAH for bringing me his grace and

mercy; I am forever grateful to my God.

I would like to seize this opportunity to thank my supervisor,

Assistant professor Dr. Kais. J. AlJumaily for his time and continuous

support during the period of my study in the college. Dr. AlJumaily

has created a deep interest within myself to explore the different

potential in the field of ultraviolet radiation and has also inspired me

to carry out further research in this field.

I am deeply indebted to Assistant professor . Dr. Natiq Ahmed Zaki

,without his support, I would not have been able to complete this work.

Also I would like to express my thanks to the Administration of the

Department of Atmospheric science and College of science for giving

me the chance to complete my study.

I am also grateful to all my classmates for their valuable support.

Special thanks to Dr. Ahmed Sami for providing me the data which

were used in this work. I would like to thank Dr. Jay Herman for

providing me (TOMS) data from NASA.

Also I would like to express my gratitude to my great friends; Mr.

Jasim Hamid, Dr. Abdulhadi, Dr. Osama Tariq and my close friend

Mr. Ayad Abdul Karim.

Finally I would like to thank all my family members for their patience

during my Study.

Ali M AL-Salihi [email protected]

I

Abstract The increased understanding of the factors effecting the UV levels reaches on

earth surface has become an important concern which deals with ozone

depletion.

Modeling of the radiative transfer in the atmosphere has become an important

tool for estimating the radiation at ground level for different altitudes in the

atmosphere. Modeling has became an important tool for understanding the

complex variability related to solar radiation and factors influencing the solar

radiation spectral at ground. Radiative transfer models make it possible to

estimate the radiation available for the photochemistry in the atmosphere when

models are run.

This thesis focuses on SMARTS 2.9.5 model which is widely used in this field ,

this package contains a set of FORTRAN codes with a lot of possible input

information. The model used in this thesis gives both the diffuse and direct

radiation in the UV, visible and infrared Radiation as output, It offers many

options for different input parameters such as extraterrestrial radiation,

atmospheric trace components such as ozone, aerosols, atmospheric

composition, and ground conditions such as surface type and albedo.

This thesis performs the work model evaluation and determination of the above-

mentioned model. The SMARTS 2.9.5 model achieves correlation coefficient

close to (0.91) while comparing it's calculation with measurements with over

estimation close to (%5) and compared with TUV model which achieves

correlation coefficient (0.86). Sensitively study of different atmospheric

parameters such as: solar Zenith angle on global irradiance, albedo on global

irradiance, ozone on global irradiance, altitude on global irradiance have been

made. The aerosol as Impact on global UV and cloud cover effecting on global

UV level uses different solar elevation through the cloud cover conditions.

Finally an empirical relation for ultraviolet cloud modification factor (Fuv) with

R=0.93 has been obtained.

II

The Contents Title

Page Number

Chapter One: General Overview 1.1 Introduction 1

1..2 Nature of Ultraviolet Radiation 2

1.3 Absorber in the ultraviolet spectrum 3

1.4 Scattering of Direct solar radiation 4

1.5 Previews studies 6

1.6 Aim of thesis 8

1.7 Thesis organization 9

Chapter Two: Theoretical Concepts 2.1 Radiometric quantities 10 2.2 Extinction and emission 12 2.3 Angstrom’s Turbidity Formula for all Aerosols 15 2.4 Surface Reflection: The BRDF 16 2.5 Ozone Absorption 17 2.6 Uniformly Mixed Gases Absorption 18

Chapter Three: Instrumentation and Measurements 3.1 Introduction 19

3.2 Total Ozone Mapping Spectrometer (TOMS) Sensor 19

3.3 TOMS Instrument Description 20

3.4 Radiometric Calibration 20

3.5 Epply pyranometer and Ultraviolet data sets. 21

3.6 Automatic weather station and global UV sensor 22

3.7 Method of Statically Tests 24

3.7.1 Mean Bais Deviation 24

3.7.2 Root Mean Square Deviation 25

3.7.4 Correlation Coefficient 25

III

Chapter Four: Results and Discussions 4.1 Introduction 26

4.2 SMARTS2.9.5 model description 27

4.3 T.U.V4.4 model description 30

4.4 T.U.V4.4 model evaluation 31

4.5 SMARTS2.9.5 model evaluation 34

4.6 Sensitivity Studies and Atmospheric Parameters Impact on Spectral Ultraviolet.

37

4.6.1 Effect of solar zenith angle. 37

4.6.2 Effect of albedo. 39

4.6.3 Effect of altitude 40

4.6.4 Effect of ozone 44

4.7 Test of diurnal behavior of smarts output in UV-range. 46

4.8 Ozone influence on UV-B 49

4.9 Impact of aerosols and clouds on ground base ultraviolet measurements and the seasonal behavior of UV-B with seasonal behavior of ozone.

54

4.10 Impact of cloud cover on global UV irradiance. 60

Chapter Five: Conclusion and Suggestion

5.1 Conclusion 70

5.2 Suggestions and Future Works 71

References 73

Appendix

IV

List of Abbreviations Symbol Meaning

A Angstrom (10-10 meter) G Global radiation (W/m2) m.a.s.l Meter above sea level MBD Mean bais deviation NASA National Administration Space Agency O3 Ozone

RMSD Root mean square deviation S.Z.A Solar Zenith Angle SMARTS Simple Model Atmospheric Radiative transfer of

Sun Shine TOMS Total Ozone Mapping spectrometer TUV Troposphere ultraviolet and visible model UV Ultraviolet Radiation (W/m2) UVA Ultraviolet Radiation corresponding wavelength rang

between (315-400 nm) UVB Ultraviolet Radiation corresponding wavelength rang

between (280-315nm) UVC Ultraviolet Radiation corresponding wavelength rang

between (200-280 nm) WHO World Health Organization WMO World Meteorological organization λ wavelength GSFC CC

Goddared Space Flight Center Correlation Coefficient

V

List of Figures

PageTitle 1 Solar Spectrum 1.1. 3 Ozone concentration with altitude. 1.2 5 Scattering of electromagnetic radiation. (a) Rayleigh scattering

(b) mie scattering. 1.3

10 Illustration at the definition of spectral radiance 2.1 11 Illustration of the calculation of the spectral irradiance by

integrating the spectral radiance over the hemisphere above the shaded horizontal surface

2.2

13 A beam, or pencil of radiation travelling a distance ds from A1 of unit area to surface A2

2.3

17 Geometry and symbols for the definition of the BRDSF, [the α is the backscattering angle]

2.4

22 Epply Global ultraviolet Radiometer and Global solar Radiation Radiometer

3.1

23 Ultraviolet sensor maintained on the Automatic weather station in AL-Mustansiriyah university

3.2

23 The Automatic weather station in Al-Mustansiriyah university 3.3 33 Comparison of UV global irradiance based on measured and

calculations using TUV 4.4 model. 4.1

36 Comparison of UV global irradiance base on measured and calculations using SMARTS 2.9.5 Model

4.2

37 The variation of direct irradiance with wavelength at different solar zenith angles in the absence of aerosols.

4.3

38 The variation of direct irradiance with wavelength at different solar zenith angles in the presents of aerosols.

4.4

40 The variation of global irradiance with wavelength at different surface albedo in the absence of aerosols

4.5

41 The variation of global irradiance with wavelength at different surface albedo in the presents of aerosols .

4.6

42 The variation of global irradiance with wavelength at different altitude with absence of aerosols.

4.7

43 The variation of global irradiance with wavelength at different altitude& with presents of aerosols.

4.8

44 The variation of the global irradiance with wavelength at different total ozone column with absence of aerosols.

4.9

45 The variation of global irradiance with different total ozone column with presents of aerosols.

4.10

46 The variation of extinction at a monochromatic wavelength of 305 nm with altitude.

4.11

VI

48 Comparison of diurnal behavior of UV global on measurements and calculations using SMARTS 2.9.5. Model presented on subfigures (a, b, d and e) in 10 January, 11 February, 26 march, 1september23 June, 8 July 1998.

4.12

49 UV-B irradiance calculations as a function of total ozone. 4.13 51 Correlation for 50º solar zenith angle for selected clear days of the

year 2002. 4.14

52 Total ozone column and UV-B irradiance seasonal behavior for 50º solar zenith angle for selected days of year 2002

4.15

52 Seasoned behavior of ozone and UV-B percentage variation in relation to its average for 50º solar zenith angle for selected days for year 2002.

4.16

55 The annual course of Total ozone column based on TOMS data over Baghdad city in the year 2002.

4.17

56 .The annual course of UV-B irradiance based on Meteor data base for the year 2002

4.18

57 The annual course of global UV, UV-B irradiance and Total ozone column for the year 2002.

4.19

58 Comparison between measurements and calculated diurnal variation of global UV radiation on 3 June 2007.

4.20

58 Comparison between measurements and calculated diurnal variation of global of global UV radiation on 28 June 2007

4.21

59 Comparison between measurements and calculated diurnal variation of global UV radiation on June 2007.

4.22

61 Ultraviolet global irradiance vs. cloud cover for different solar elevation angles.

4.23

62 Ratio of global ultraviolet irradiance to total solar irradiance UV/G vs cloud covers for different solar elevation angles.

4.24

64 Ratio of global ultraviolet irradiance to total solar irradiance UV/G and hemispherical ultraviolet transmittance K tuv, vs. cloud cover for different solar elevations

4.25

65 UV global irradiance Vs optical air mass 4.26 65 Ultraviolet cloud cover modification factor FUV vs cloud cover for

different solar elevation angles. 4.27

68 Ultraviolet cloud modification factor, FUV total global cloud modification factor FG

4.28

69 Ratio of UV global cloud modification factor FUV to total global cloud modification factor FG vs cloud cover

4.29

VII

List of Tables

Title page

Chapter Three

3.1 Characteristic of total ozone column database 20 3.2 Apply ultraviolet pyrometer specifications 21

Chapter Four

4.1 Values for the characteristic parameters for the standard models and Braslou and Davels., 1973 model included in SMART 2.9.5

29

4.2 The models depending on relative humidity 30 4.3 Values for the characteristic parameters of the

model TUV 4.4 31

4.4 Statically results concerning TUV 4.4 model behavior

32

4.5 Considering the modification suggested by Bosca et.al., (1997)

33

4.6 Statically results concerning TUV 4.4 model behavior with modification of Bosca et.al., (1997)

34

4.7 Statically results concerning SMARTS 2.9.5 model behavior with different aerosol models

35

4.8 Correlation coefficient (R) and their confidence level (CL), A and B values for linear fit (y=A+BX) for each solar zenith angle

54

4.9 Statically parameters for cloud modification factor for different cloud cover

67

Chapter One General Overview

1

CChhaapptteerr 11 GGeenneerraall oovveerrvviieeww

1.1 Introduction The sun emits energy across the electromagnetic spectrum which is shown in figure (1.1), but mainly in wavelength between 200 and 400 nm. Energy emitted as a function of wavelength is very similar to what is expected from a black body with a temperature of 6000 K , which is close to the sun's photosphere temperature, while the averaged energy flux density emitted at the photosphere is 6.2×107 W/m2 (Weeb et al ,1980), The distribution of radiation depending on wavelength (the so-called spectrum of emission) covers ranges (or bands) called infrared (larger than 720 nm), visible (VIS) (between 400 and 720 nm) and ultraviolet (UV).The ultraviolet radiation having wavelength in three bands in the range 200-400 nm, UVC corresponds to wavelength from 200-280 nm, UVB corresponds from 280 to 315 nm and UVA corresponds to wavelengths from 315 nm to the visible lower limit (400nm) (Webb,1998).

Figure 1.1: Solar Spectrum [WMO, 2002].


2

Human eyes can detect wavelength in the region of spectrum from 400 nm to

700 nm, i.e. they can detect the visible region of the spectrum. All the seven

colors of light fall inside a small wavelength band and visible light have

wavelength in order of billionths of a meter. The red light is at the end of the

visible spectrum with wavelength of 630 nm and in the opposite side of the

spectrum is the blue light with 430 nm. The blue light is more energetic than

the red light and less energetic than the violet light which has even shorter

wavelength (WMO, 2002).

1.2 Nature of Ultraviolet Radiation According to the previously mentioned limits of ultraviolet radiation

divisions. the boundary between UVB and UVA is somewhat ambiguous, and

some authors set it at 320 nm, based on the significant biological effects of

radiation with wavelength between 315 and 320 nm. However, most

international agencies and scientific research centers such as; World Heath

Organization (WHO, 2002); European Union's Action (Taalas et al ., 2000),

and according to Frederek et al., (2000), radiation in the UV band is received

at the top of the atmosphere is 8.3% of the total solar radiation.

When radiation is emitted by the sun enters into the earth's atmosphere,

Radiation is modified by several phenomena which will be explain in the

next section of this chapter, which are classifies them into absorption and

scattering (which together cause the beam extinction).

One of the most important phenomena that influence UV radiation is the

absorption by photochemical reactions, those phenomena in general are

involved in the ozone creation-destruction cycle which take place basically in

the stratospheric, virtually absorb all radiation in the UVC band even if

stratospheric ozone greatly reduced, all UVC which would still be totally

absorbed as shown in figure(1.2) (Mardonich et al ., 1998).However,


3

radiation within the UVB and UVA bands is not totally absorbed in the

stratosphere in amount depend relatively on tropospheric ozone content and

the presence of other trace gases , aerosols and clouds.

Figure (1.2): The Ozone concentration with altitude

(WMO, 2002).

1.3 Absorbers in the Ultraviolet Spectrum The ozone (O3) is the principal absorber in the UV. Atomic oxygen and

nitrogen absorbs x-rays and other short-wave radiation continuously are up

to 85.0 nm. As these two gases are found high in the atmosphere, no radiation

of wavelengths less than 85.0 nm passes through to the lower atmosphere.

Oxygen and Nitrogen absorb solar radiation in a number of overlapping

bands in wavelengths below 200 nm. Since the upper (beyond 90 km) and

lower atmospheres are composed primarily of these gases (atomic and

molecular oxygen and nitrogen), no radiation below 200.0 nm reaches the

surface of the earth. This is fortunate, because this far-UV radiation degrades

materials colors, which are harmful to human beings. Ozone exhibits a


4

number of absorption bands beyond 200.0 nm in the UV, and Ozone has a

strong absorption band from 200.0 to 300.0 nm, weaker bands from 300.0 to

350 nm.

1.4 Scattering of Direct Solar Radiation The scattering of electromagnetic energy in the atmosphere is a complex

process. The smallest scattering particles are molecules which can be

considered to be much smaller then wavelength of even visible light.

Rayleigh scattering describes the scattering by atmospheric molecules at all

wavelengths. When the scattering particles get larger, so they become at least

comparable in size to the wavelength, Mie scattering must be used. When the

particle size is of the order of the wavelength of the incident radiation, Mie

theory is applicable. For mathematical treatment, a convenient parameter to

express the size of the scattering particle is π D/λ, where D is the particle

diameter. Let n be the index of refraction and λ the wavelength in

micrometers. It is considered that;

(1) When πD/λ < 0.6/ν, scattering is governed by Raleigh's theory, and in a

cloudless atmosphere applies to air molecules, most of which have a size of

about 1Å.

(2) When πD/λ > 5, scattering is chiefly a diffuse reflected process seldom

occurring in the Earth’s atmosphere.

(3) When 0.6/n < πD/λ < 5, scattering is governed by Mie’s theory and

applies to scattering by particles of a size greater than 10Å, such as aerosols.

Figure1.3 shows the difference between the Rayleigh and Mie modes of

scattering. In the Rayleigh mode (figure1.3a), the scattering process is

identical forward and backward directions. In addition, scattering is

maximum in forward backward directions. It is minimum at 90 to the line of


5

incidence. Greater scattering occurs when incident radiation is of a shorter

wavelength. In Mie scattering (figure 1.3b), more energy is scattered in a

forward direction than in the backward direction. Furthermore, as the particle

size increases, so does forward scattering, and shape of the scattering

"balloon" is altered Iqbal, [1983]. The radiation which is scattered by one

particle strikes other particles in the medium, and this process, called multiple

scattering, continues in the atmosphere. In a clean dry atmosphere, about half

of the energy thus scattered goes back into space and the other half reaches

the ground as scattered radiation. In an atmosphere containing dust particles,

more scattered energy reaches the ground because of greater forward

scattering. The largest atmospheric scatterers are the raindrops and hailstones.

Their scattering must be calculated using Mie theory at all wavelengths. Most

other scatterers are treated by Rayleigh scattering approximation at longer

wavelengths.

Figure (1.3): Scattering of electromagnetic radiation.

(a)Rayleigh scattering. (b) Mie scattering.

Even Mie scattering is an approximation for almost all particles found in the

atmosphere. Few particles are spheres or ellipsoids, the shapes of particles

assumed in the Mie scattering theory. The Mie formulation takes absorption


6

into account, and lacking any other practical method for calculating scattering

by non-spherical particles, is frequently used by approximating complex

shaped aerosols as distribution of spheres. Just how well this distribution

approximates the actual scatterers is largely unknown.

Seldom has a scattering experiment provided measurements at more than a

small number of angles. Even more seldom, probably never, has the actual

distribution of aerosols been known. The angular scattering function can be

complex. There is really no good way for categorizing the shapes and sizes of

atmospheric aerosols. Rayleigh developed his scattering theory on the basis

of the charge polarization produced in the scattering particle by the

electromagnetic wave. The redistribution of the charge on the particle can be

regarded as a current issue. The interaction of this current (rapidly changing

current produces electromagnetic waves) and the incident electromagnetic

wave interact produce an altered wave. The modified Rayleigh assumes that

the particle was much smaller than the wavelength being scattered. Instead of

going through a derivation of Rayleigh, the same result can be obtained as the

small particle limit of the Mie theory. This allows the index of the refraction

to be complex, something not possible with Rayleigh scattering (Kyle, 1991).

1.5 Previews Studies The measurement of solar ultraviolet (UV) radiation has increased

tremendously in the past 25 years, both from interest in UV itself and its role

in climate changes, The effect of increased UV-B radiation on plants and

terrestrial ecosystem, which might arise from stratospheric ozone depletion,

have been studied using a variety of experimental and modeling systems. The

point relevant radiation quantity of many biological systems which represents

a total radiation incident, was investigated by Mordonich , (1984), then the

same author (Mardonich, 1987) who studied the climatology of (UV) at the


7

earth surface and lower atmosphere. Ilyas,(1987) investigated the relation

between cloud cover effect on UV irradiance. There are several studies

utilizing empirical study of the cloud effect on UV radiation as a direct

function of cloud cover such as Kuchinke et al ., (1991) ; Martinez et al .,

(1994) studied the ratio of UV/G which provide the relative importance of UV

irradiance on total solar irradiance at the earth surface Instrumentation to

measure the spectral solar ultraviolet radiation researched by Müller et al.,

1996; kudish et al., (1997) has made an analysis of UV radiation in Dead Sea

basin. Webb , (1999) studied the change in strospheric ozone concentration

and Mayer et al., (1997) investigated the climatology of spectral UV with

long term using UV measurements and UVSPEC modeling, Manual et al .,

[1998] compromised of cloudless sky ultraviolet radiation at two sites in

southwest Sweden, Foyo-Mereno et al ., (1998) showed that UV radiation

exhibits daily seasonal and local variability associated with cloud cover

variation and also studied the cloud effect as a function on solar spectral

range. Krzyscin, (2000) investigated the effect of stratospheric ozone profile

variability on ultraviolet radiation trends in Poland.

A number of campaigns have been employed in order to achieve some

measurements of the spectral solar ultraviolet radiation (Hofzumahaus et al .,

1999; Shetter and Müller, 1999). Kylling et al., (2000) determined the surface

albedo Impact on global and direct UV irradiance measurements: Zenfer etal

(2000) estimated UV-B doses from the satellite observation.

Dubronvsky, (2000) analyzed UV-B measurements at two stations in the

Czech Republic. Barrtlet, (2000) studied the changes in ultraviolet radiation in

the 1990 in reading [England] Webb, (2000) presented the ozone depletion

impact on environmental UV-B radiation. Tena, (2000) estimated the direct

ultraviolet spectral irradiance in Valencia (Spain) and compared its

calculations with measured values.


8

Josefsson et al., (2000) estimated the effect of hydrometers in the atmosphere

such as cloud amount, type and precipitations on global UV irradiance.

Lokkala (2001) studied a decade of spectral UV measurements at saodankyla

(Finland), Christain, (2003) used a moderate bandwidth multichannel

instrument to measurement UV.

Malinovic et al., (2003) used NEOPLANTA model to estimate solar

ultraviolet irradiance [290-400 nm] model evaluation study. Civen et al.,

(2003) employed a long – term global earth surface UV radiation exposure

derived from TOMS satellite measurements. Wendisch, (2003) studied the

vertical distribution of spectral solar irradiance in the vertical distribution of

spectral solar irradiance in the cloudless sky conditions. Josefsson, (2004) has

measured UV radiation in Ncrrkőping between 1993-2003. Bernhard et al.,

(2004) used a network data in order to study UV and ozone climatology at

South Pole. Gusrnieri , (2004) investigated the anti correlation of ozone and

UV-B at fixed solar zenith angel in southern Brazil. Miguel , (2005) studied

the ultraviolet radiation at a rural area of Spain. Tadros et al., (2005) has made

a comparison study between SPECTRAL and SMARTS model and employed

the direct normal solar irradiance in different bands for Cairo and Aswan in

Egypt. Pinedo, (2006) showed the spectral signature of ultraviolet solar

irradiance in Zacatecos.

1.6 Aim of Thesis The main objective of this work is to test and compare the output of the used

models in this thesis with the available measurements and to create an

evaluation for these models and shows their flexibility on using various

atmospheric parameters input. The present work will focus on the sensitivity

studies of different atmospheric parameters that would be performed.


9

Sensitivity studies on the effect of solar zenith angle on direct irradiance, the

effect of ozone on global irradiance, estimating the attenuation of direct

irradiance in the atmosphere, the effect of altitude on global irradiance and

the effect of aerosols on direct irradiance would be carried out. The general

purpose of this thesis is to obtain a clear understanding of ultraviolet radiation

because it became an important detection of the depletion of ozone caused by

anthropogenic sources.

1.7 Thesis Organization Chapter1 presents a general introduction to solar spectrum and describes the

properties of Ultraviolet radiation and its wavelength range, The next part of

this chapter reviews the previous studies then explains the aims of the thesis

Chapter 2 reviews the theoretical concepts Chapter 3 provides information

about the measurements of Ultraviolet radiation and satellite data obtained

from TOMS, METEOSAT data, UV sensor maintained on Energy and

environmental researches center on Al-jadiriyah location and on AL

Mustansiriyah automatic meteorological station. Chapter 4 presents the

experiments which were made using [SMARTS2.9.5 and TUV4.4] and the

comparison between Models output and real measurements in order to

evaluate the performance of these models in order to employ them in this

work to assess the solar zenith angle, albedo, ozone, aerosols, altitude effect

on Ultraviolet radiation , This chapter also investigates the impact of Ozone

on UVB and obtains the strong anitcorrelation between these factors. Finally,

the effect of cloud cover on global UV is presented.

Ch

2.1Sev

me

The

uni

the

me

pho

r: a

lie

freq

the

hapter Tw

1 Radiomveral diffe

asurement

e spectral

it area. Pe

waveleng

asured in

otons eme

as shown

within a c

quencies l

photons.

F

wo

metric Qferent, but

t of radiat

l radiance

r unit soli

gth λ. at

Wm2nm-1

rging from

in Figure

cone of sm

lie betwee

Figure 2.1:

CTheo

Quantitiet related,

tion. The m

e (or mon

id angle, p

a point r1 The spec

m a small

2.1 . Con

mall solid

en ∆

Illustratio

10

Chapteroretical s

quantitie

most impo

nochromat

per wavel

r. in the

ctral radia

area ∆ w

nsider thos

angle Ω∆

∆ . Then

n at the de

r TwoConcep

es are us

ortant once

tic radian

ength inte

direction

ance can b

with unit n

se photon

centered

∆ Ω∆

finition of s

Theor

pts

sed in th

e are descr

nce) L(r,s)

erval in th

of the u

be visualiz

normal s,

ns whose m

on the dir

is the ene

spectral ra

retical Co

e descrip

ribed as fo

) is the p

he neighbo

unit vector

zed in term

centered a

momentum

rections an

ergy trans

adiance.

oncepts

ption and

ollows.

ower per

orhood of

r s. It is

ms of the

at a point

m vectors

nd whose

ferred by

Ch

The

in t

wav

The

uni

λ,

obt

one

wh

The

thro

the

hapter Tw

e radiance

the directi

velength.

e spectral

it area, per

at a poin

tained from

e side of th

ere dΩ is t

Figu

e irradian

ough a sur

integral o

wo

e L(r,s) is

ion of the

l irradianc

r unit wav

nt r throug

m the spe

he surface

the elemen

ure 2.2 : Illu by abo

nce (or flu

rface of n,

of the radia

the powe

unit vecto

,

ce (monoc

velength i

gh a surf

ectral radi

e:

,

nt of solid

ustration ofintegrating

ove the sha

ux density

, i.e., the i

ance over

11

er per unit

or s; in ot

,

chromatic

interval in

face of no

iance by t

,

d angle as

f the calculg the spectraded horizo

y) F(r,n) is

integral of

a hemisph

t area, per

her words

c irradianc

n the neigh

ormal n;

the integr

. Ω

shown in

lation of thral radiancontal surfac

s the pow

f a point

here:

Theor

r unit solid

s it is the

(2.1)

ce) ,

hborhood

its unit i

ation over

(2.2)

figure 2.2

he spectral ice over the ce.

wer per uni

over wa

retical Co

d angle at

integral o

is the p

of the wa

is Wm-2

r a hemis

)

2 :

irradiance hemispher

it area at

avelength,

oncepts

a point r

f over

power per

avelength

It is

sphere on

re

a point r

, and also

Chapter Two Theoretical Concepts

12

, , λ L r, s . Ω (2.3)

its unit is Wm-1.

Irradiance has specific direction associated with it; for example, if the surface

in question is horizontal and the normal n points upwards, then the irradiance

under consideration is associated with upward-moving photons.

2.2 Extinction and Emission Consider a beam of radiation of unit cross-sectional area, moving in a small

range of solid angles about the directions; as shown in Figure2.3. If the

photons experience absorption or scattering in a small distance ds along the

beam, due to the presence of a relatively active gases (or gas containing a

suspension of solid particles or liquid droplets), then the spectral radiance

will reduced.

The physics of the process is complex; however, it may be summed up in

Lamberi’s law, which states that the fractional decrease of a spectral radiance

is proportional to the mass of absorbing or scattering material encountered by

the beam in a distance ds. Since the beam has unit cross-sectional area, this

mass is ,ds, where , is the density of the radioactively active gases (or gas

containing a suspension of solid particles or liquid droplets), so

2.4

The quantity is the extinction coefficient; it is the sum of an absorption

coefficient and scattering coefficient defined in an obvious manner in

terms of the contribution to . from the absorption and scattering,

respectively:

Ch

The

and

an

con

pho

of E

into

con

Inc

obt

hapter Tw

e extinctio

d it can be

emperical

ntaining a

otons of w

Equation

o the bea

nvenient to

luding bo

tained:

wo

Figure 2.3

on coeffic

e regarded

l quantity

suspensio

wavelength

(2.4), to

am. This t

o write it

oth extinc

3 :A beam, ds from A

cient ge

d as a calc

y, to be d

on of soli

h λ , an ex

represent

term will

as

ction and

13

, or pencil’ Al of unit a

enerally d

culable fro

erived fro

id particle

xtra term m

the addit

be propo

, whe

d emission

(2.

of radiatioarea to surf

depends on

om detaile

om measu

es or liqui

must be a

tional pow

ortional to

ere (s) is

n the rad

Theor

5)

on travellinface A2.

n tempera

ed quantum

urements.

id droplet

added to th

wer per un

o the mas

s called th

diative-tra

(2.6)

retical Co

ng a distanc

ature and

m mechan

If the ga

ts) is also

he right -h

nit area in

ss s,

he source f

ansfer equ

oncepts

ce

pressure,

nics or as

s (or gas

emitting

hand side

ntroduced

, so it is

function.

uation is


14

If , and are given as functions of distance, a formal solution of the

radiative- transfer equation can be obtained as follows. The optical path ‘is first

introduced and is defined as

′ ′ d ′ (2.7)

where

2.8

is the start of the path; then Equation (2.6) can be written as (2.8)

using the integrating factor exp( ).

Equation (2.7) is integrated to obtained:

(2.9)

if spectral radiance equals at the point so the

′ (2.10)

In the absence of emission the spectral radiance falls exponentially, decreasing

by a factor of e over a distance corresponding to unit optical path. A region is

said to be optically thick at a wavelength λ if the total optical path through

the region is greater than 1 and optically thin if the total optical path is less

than 1. A photon is likely to be absorbed or scattered within an optically thick

region, but likely to traverse an optically thin region without absorption or

scattering [Andrews, 2000].


15

2.3 Angstrom’s Turbidity Formula for All Aerosols From moon’s coefficient for dust attenuation, the number of particles per unit

volume can be varied. However, the coefficient is independent of the size of

dust particles. The next step, then, is to incorporate the particles size in the

attenuation formula, Furthers since attenuation effects of scattering and

absorption by dust are difficult to separate. Angstrom suggested a single

formula generally known as Angstrom‘s turbidity formula is given by the

following:

2.11

where , is called Angstrom turbidity coefficient, is the wavelength

exponent, and the wavelength is in micrometers. It is called “turbidity” because

scattering of solar radiation by dry air molecules is called turbidity of the

atmosphere (in the optical sense). Consequently includes attenuation due

to “dry” as well “wet” dust particles. i.e. all aerosols.

In Equation (2.11), which varies from 0.0 to 0.5 or even higher, is an index

representing the amount of aerosols present in the atmosphere in the vertical

direction. The wavelength exponent a is related to the size distribution of the

aerosol particles. Large values of indicate a relatively high ratio of small

particles to large particles. Generally, a has a value between 0.5 to 2.5: a value

of 1.3 is commonly employed, since it was originally suggested by Angstrom.

A good average value for most natural atmosphere is a 1.3 0.5

At a fixed value of a lower value of signifies higher visibility i.e., higher

atmospheric transparency. By inference it can be concluded that lower values

of (larger average particle size) would result in higher amounts of solar

radiation reaching the ground.

Using Angstrom’s turbidity formula, aerosol transmittance can be written as


16

(2.12)

where ma is the optical path length [Iqbal, 1983].

2.4 Surface Reflection: The BRDF The concepts of reflectance and transmittance are more complicated than those

of emittance or absorptance. Since they depend upon both the angles of

incidence and reflection or transmission. Referring to figure2.4, we consider a

downward-moving angular beam of radiation with intensity Iλ(Ω ) within a

cone of solid angle d around Ω . Then the energy incident on a flat surface

whose normal is directed along the z axis (figure2.4) is Ω cos

Denoting by dIλr+(Ω ), the intensity of reflecting light leaving the surface

within a cone of solid angle around the direction Ω , we define the

bidirectional reflectance distribution function (BRDF), as the ratio of the

reflected intensity to the energy in the incident beam:

, Ω,Ω = Ω′

Ω (2.13)

We note that dIλr+(Ω ) is a first-order differential quantity that balances the

differential in the denominator, so that is a finite quantity. Adding the

contributions to the reflected intensity in the direction Ω from beams incident

on the surface in all downward directions, we obtained the total reflected

intensity

Ω′)= Ω′ cos , Ω,Ω Ω′ (2.14)

Ch

Th

dire

obs

2.5

The

wh

abs

hapter Tw

us, the re

ections tim

servation a

Figure 2.4

5 Ozone

e Bouguer

ere

is optical

sorption co

wo

eflected in

mes the B

angles und

4: Geometr the backsc

Absorpt

r law is us

I

mass,

oefficient.

ntensity i

BRDF for

der consid

ry and symbcattering an

tion

sed to dete

s the ozon

is reduc

17

s the inte

r that part

deration.

bols for thengle].

ermine the

ne optical

ced path l

egral of th

ticular com

e definition

e ozone ab

thickness.

length (in

Theor

he energy

mbination

n of the BRD

bsorption a

(2.15)

.

atm - cm

retical Co

y in each

n of incid

DF,[The an

as follows

m), is

oncepts

incident

ence and

ngle is

:

s spectral


18

Ozone absorbs strongly in the UV. Recent spectroscopic laboratory data from

Daumont et.al. [1992] are available for the Hartley – Huggins bands at 0.01 nm

resolution.

The original data were smoothed in 1 nm steps. Up to 344 nm. From 345 to

350 nm, data from Moline,[1986] were downgraded from their original

resolution of 0.5 nm between 351 and 355 nm, data from Cacciani et.al. [1989]

were smoothed to 1 nm. The same procedure way was performed between 356

and 365 nm where the absorption coefficients were derived from the data in

MODTRAN2.

2.6 Uniformly Mixed Gas Absorption

Some atmospheric constituents known as the "mixed gases" (Principally O2

and CO2) have both monotonically decreasing atmospheric concentration with

altitude and significant absorption bands in the infrared. Using the analysis of

pierluissi ,[1986] and Tsai ,[ 1987], the mixed gas transmittance is defined as:

(2.16)

where is the gas mass, is the spectral absorption coefficients, and is

the altitude – dependent gaseous scaled path length. The exponent a was

obtained by averaging the data tabulated by Pierluissi Tsai [1986, 1987] where

a = 0.5641 for λ < 1 µm

Chapter Three Instrumentation and Measurements

19

Chapter Three

Instrumentation and Measurements 3.1 Introduction This chapter, introduces the measurements and types of radiometers, which are

used to obtain the measurements employed in this work.

Generally, we employ various types of measurements such as UV doses

measured by Epply pyrnometer in Al-Jadiriyah location and UV sensor mounted

on AL-Mustansiriyah meteorological station also we used ozone and UV-B data

from total ozone mapping spectrometer (TOMS) and meteor-3 data base

respectively additionally we employ the observations of cloud cover obtain from

Iraqi meteorological office.

3.2 Total Ozone mapping spectrometer (TOMS) sensor TOMS instrument developed by National Aeronautics & Space Administration

(NASA) Goddard Space Flight Center (GSFC). The TOMS instrument was

designed to enable long-term daily mapping of global distribution of the earth’s

atmospheric Ozone. They have been such missions, and this deals with data

obtained from TOMS on board Earth Probe (1997-2005) missions.

TOMS makes 35 measurements every 8 seconds each covering a width of 30 to

125 miles (50-200 km) on the ground, strung along a line perpendicular to the

satellite path motion.

TOMS uses the ratio of back scattered earth radiance to solar irradiance at

specific wavelength to infer total ozone and Table (3-1) shows details of the

TOMS ozone data (Herman et al .,1996).


20

Table (3-1): Characteristics of the total Ozone column datasets

Satellites Earth Probe

Instrument Total Ozone mapping spectrometer (TOMS)

Parameter Total Ozone column

Temporal coverage 1997-2005

Temporal resolution Daily data

Special coverage Global

Special resolution 1.25 (latitude) × 1.25 (Longitude)

3.3 TOMS Instrument Description The TOMS Ultraviolet sensors on board the Meteor-3 satellite measured incident

solar radiation and backscattered global ultraviolet and Ultraviolet-B.

Total ozone was derived from these measurements. To map total ozone, TOMS

instruments scan through the sub-satellite point in a direction in perpendicular to

the orbital plane.

Backscatter ultraviolet instrument measures the response to solar irradiance by

developing ground aluminum diffuser plate reflects sunlight into the instrument

(Herman, et al ., 1996).

3.4 Radiometric Calibration The calibration of the TOMS measured earth radiance and solar irradiance may

be considered separately. The earth radiance can be written as a function of the

instrument coefficient counts in the following way:

Im(t) = Cr Kr Gr fins(t) (3.1)

where

Im(t) : derived earth radiance


21

Cr : counts detected in earth radiance mode

Kr : radiance calibration constant

Gr : gain range correction factor

fins(t): correction for instruments changes

The measured solar irradiance Fm can be written as:

Fm(t) = Ci Ki Gi fins(t) ⁄ g Ω(t) (3.2)

where

g : relative angular correction for diffuser reflectivity

Ω(t): solar diffuser plate reflectivity

3.5 Epply Pyrometer and Ultraviolet Data Sets There are many types of sensor can be used to measure ultraviolet radiation.

Epply ultraviolet radiometer (photometer and global solar radiation shown in

Figure (3.1) is used for meteorological purposes and consisting of western

selenium barrier-Layer photoelectrical with a sealed-in quarters window. A band

passes through the filter to restrict the wavelength response of the photocell

according the selectable range (295-385 nm). Table(3-2):Epply Ultraviolet Pyrometer specifications

Sensitivity 150 µ volt/wm-2

Response time 1 seconds

Linearity ± 2% from 0 to 70 w/m2

Size 5.75 inch diameter, 6.75 inch heights

Cosine response ± 2% from 0 to 70 solar zenith angle

weight 6 pounds


22

Figure (3.1): Epply Global Ultraviolet Radiometer and Global Solar

Radiation Radiometer.

The data from a radiometric station which is installed by the Environmental and

Energy research center in Al-Jadiriyah location (33.34No, 44.45Eo, 34 m .a.s.l).

The measurements were taken hourly.

In this work, we employ nine months of hourly measurements that allows us to

cover a relative wide range of different solar elevations and seasonal conditions.

3.5 Automatic Weather Station and Global UV Sensor

Global ultraviolet measurement used in this work was obtained by Davies UV

sensor which is shown in figure (3.2) mounted on the automatic weather station

which is shown in figure (3.3) installed on the roof of the Department of

Atmospheric science in Al-Mustansuriyah university (Lat 3.33No long 44.44Eo

34 masl).


23

The equipment measures the broad band radiation in the interval of (280-400nm)

that corresponds exactly to global UV range.

Figure (3.2): Ultraviolet sensor maintained on

the Automatic Weather Station in

Al-Mustansiriyah University

Figure (3.3): The Automatic Weather Station in

Al-Mustansiriyah University


24

The equipment consists of a sensor associated with optical parts such as quartz

fillers. The sensor output corresponds to a DC voltage level propertied to global

ultraviolet radiation incident on the diffuser, located inside the quartz dome.

The equipment is connected with wireless connection to a data logger able to

collect data for a period of about 28 days.

The data are recorded at a sample rate of one measurement per 15 minutes.

3.7 Method of Statitical Tests This thesis employs two models for predicting or estimating the radiation

reaches earth surface. Comparison of an individual calculated value against a

measured value is not a sufficient test of accuracy of a predictive model rather it

is necessary to analyze a large number of data.

For solar radiation models , a number of useful statically tests are based on the

calculation of Mean Bais Deviation (MBD), Root Mean Square Deviation

(RMSD), Correlation Coefficient (r), these statically tests are defined below.

3.7.1 Mean Bais Deviation The MBD is an indication of the average deviation of the predicted value from

the measured value. It is defined by:

∑ (3.1)

Where predicted value , measured value, and N the number of

observations. Ideally a zero of MBD should be obtain (Willmott,1982).


25

3.7.2 Root Mean Square Deviation The RMSD is the measure of the variation of the predicted value around the

measured value which is defined as follows:

∑.

(3.2)

The RMSD is always positive ; However a zero is ideal. It may be noted that a

few large variations of the calculated amount of radiation from the measured

radiation can substantially increase RMSD (Willmott,1982).

3.7.3 Correlation Coefficient The correlation coefficient is a test of the linear relationship between the

calculated and measured value which is defined by

∑∑ ∑ . (3.3)

Where yi is the estimated value , xi is the measured value , , are the mean

value of the estimated and measured values respectively and N is the number of

the values (Willmott,1982).

Chapter Four Results and Discussion

26

Chapter Four

Results and Discussion 4.1 Introduction Since the discovery of the ozone depletion in Antarctic and the globally

declining trend of stratospheric ozone concentration, public and scientific

concern has been raised in the last decades. A very important consequence of

this fact is the increased broadband and spectral UV radiation in the

environment and biological effects and health risk that may take place in the

near future. The absence of wide spread measurement of this radio metric flux

has led to the development and use of alternative estimation procedures such

as the parametric approached. Parametric models compute the radiant energy

using the available atmospheric parameters. Some of these parametric models

compute the global solar irradiance at surface level and different altitudes by

the addition of its direct beam and diffuse components. This study presents a

comparison between two models that deal with cloudless sky

parameterization schemes, both models provide an estimation of solar spectral

irradiance that can be integrated spectrally within the limits of interest.

For this test we have used data recorded in a radiometric station located at

Baghdad city (33.34 °N, 44.45°E, 34.m.a.s.l) in Aljadiriyah location. The

data base includes hourly values of global UV measurement covering the

selected measurements (Four times a day for three months) of the year 1998.

Ultraviolet radiation (UV) is detrimental to various types of organisms,

including humans, animals and plant. According to the degree of damage, UV

radiation which is divided into three bands: UV-A (315-400 nm). UV-B (280-

315 nm), and UV-C (200-280 nm). UV-A is the least energetic and may cause

suntan, whereas UV-C is the most powerful, which can cause mutations and

even death of a small amount of exposure.


27

The damage caused by UV-B is somewhere in between. Until recently, the

Earth's atmosphere allowed for some UV-A, a little UV-B and no UV-C

radiation reaching the ground gases (CO2, N2, etc.), However, the shielding

effect of ozone layer is diminishing due to ozone depletion, and surface –

observed UV-B which has shown a significant upward trend (WMO, 1998).

4.2 SMARTS Model Description The SMARTS model (simple model of Atmospheric Radiative Transfer of

sunshine) was first proposed by Gueymard , (1993) being the last version of

the result of series of additional improvements by Gueymard , (1995),then

after about ten years the final version proposed in December 2005. One of the

features in this version include more input parameters selection such as the

altitude above ground addition to height above sea level (Geuymard, 2005).

These options provide additional calculation of solar irradiance for different

altitudes. Two new synthetic spectra are possible to use, one is based on the

most up-to-date data (Gueymard, 2004), and the other one is interpolated

from the standard spectrum (ASTM, 2000) and two new aerosol models have

been added: DESERT-MIN (for beach ground desert conditions) and

DESERT-MAX (for sand storm conditions), altitude input as additional input

variable has been added to describe the vertical position of the object (e.g.

aircraft).

This model calculates the direct beam and diffuses radiation components

considering the separate parameterization of the various extinction processes

affecting the transfer of short wave radiation in cloud less atmosphere. The

solar extraterrestrial used in the model covers the wavelength range 280nm

and 4020nm with a resolution of 1nm and 0.5 nm in the range between 280

nm – 400nm (Gueymard , 2005).


28

The model permits the consideration of different aerosol model (standard

models and models depending on relative humidity) or the choices of a

particular model define by the user. The model has eleven aerosols model,

two models are proposed by (Breaslau and Dave ., 1973), B & Dc (aerosol

type C) and B & D (aerosol type C1) additionally, there are four models

proposed by Shettle and Fenn ., (1979) that depend on relative humidity:

MAR (maritime), QUR (rural), URB (urban) and TRO (troposheric), the last

three models correspond to standard atmospheres [ASTM,2000], SCONT

(continental), SMART (maritime) and SURBAN (urban), DESERT_MAX

and DESERT_MIN. The estimation of atmospheric turbidity has been carried

out from the available board band radiation following the procedure

developed by (Gueymard, 1998). This method is especially interesting

because the four widely used turbidity coefficients (Angström, Linke Schüepp

and Unsworth-Montieth) can easily interrelate without using any empirical

radiation. Gueymard ., (1998) has shown that the Unsworth-Monteith

coefficient slightly depends on both zenith angle and water vapor, the Linke

coefficient slightly depends on zenith angle but considerably on water vapor

and the Angström and Schüepp depend only on aerosols. In this way, the data

concerning the turbidity information are introduced by means of the

Schüepp's turbidity coefficient (at 0.5μm) although the model offers different

possibilities. The user can choose among the aerosol optical thickness

at(0.5μm), Angstrom's turbidity coefficient at(1μm), meteorological range or

prevailing visibility as observed airports. The aerosol models include two

average values of Angstrom's wavelength: 21 ∝∝ and for wave bands

separated by (0.5 μm) respectively, thus Angstrom's exponent ∝ is the

average value. Table (4-1) presents the value for the characteristics

parameters of the three standard aerosol models and the two models from

Braslau and Dave, (1973).


29

Table (4-1): values for the characteristic parameters for the standard models and Braslau and Dave's.,(1973) model included in SMARTS 2.9.5.

MODEL 1∝ 2∝ W0 G

B&DC -0.311 0.265 1 0.8042

B&DC1 0.311 0.265 0.9 0.8042

SMARTS 0.283 0.265 0.6 0.7471

SCONT 0.940 1.138 0.6 0.6541

URBAN 1.047 1.260 0.6 0.6085

Several of these values correspond to average value while others are fixed

value included in the models. All these models consider the Angstrom's

wavelength exponents ( 21 ∝∝ and ) and the corresponding∝ as fixed values.

For the standard models, the aerosols symmetry factors (g) present a

dependency with the wavelength in the form:

° (4.1)

(4.2)

Where the coefficients are fixed values which differ according to the

considered model. The model of Braslau and Dave ,(1973) assigns a fixed

value to w0 but the version B & DC1 includes a wavelength dependency

different from that of the standard models. Finally, both models assign a fixed

value for g.

The models depending on humidity consider the parameters 21,∝∝ and

consequently ∝ variables, that is as a function of the relative humidity, on the

hand, ω0 and g depends on both the relative humidity and the wavelength. The

dependency on wavelength is calculated through equation (4.1) and equation

(4.2), but with coefficients depending on the relative humidity.

Table (4-2) shows the minimum and maximum values and the averages values

of these parameter


30

Table (4-2): the models depending on relative humidity MODEL Mean 1∝ Mean 2∝ Mean W0 Mean G

MAR 0.43 ± 0.06 0.57 ± 0.09 0.979 0.71

RUR 0.93 ± 0.02 1.43 ± 0.02 0.6 0.68

URB 0.83 ± 0.02 1.18 ± 0.03 0.67 0.71

TRO 0.01 ± 0.02 2.37 ± 0.05 0.6 0.67

The dependency of the coefficients ( 21 ∝∝ and ) with relative humidity are:

⁄ 1 (4.3)

1 (4.4)

Where X is

cos 0.9 (4.5)

And U is the relative humidity.

Therefore, the main difference between SMARTS 2.9.5 and TUV 4.4 models,

is the capability of the former to select the aerosols model from a set of built

in models.

A common feature of both models in order to estimate UV global irradiance is

the required input data regarding ozone and aerosols characteristics. The total

ozone data have been provided by (NASA Total Ozone Mapping

Spectrometer, TOMS on the Nimbus7 satellite).

TUV 4.4 Model Description The TUV 4.4 model employed in our study corresponds to the spectral model

proposed by Madronich , [1998] which made improvements to the simple

model approached by Bird , [1984] including comparisons with results

rigorous radiative transfer and with measured spectra [Madronich, 1999].


31

The model uses the extraterrestrial spectral irradiance presented by Frohlich ,

(1981) with 1nm resolution in range 280-410 nm in order to cover the

spectral range of our data needed. The required input parameters are local

geographic coordinates, total ozone column, pressure and temperature,

perceptible atmosphere water vapor and aerosol information, the aerosol

information required by the model is the aerosol optical depth at 500 nm, the

model uses fixed values for the remaining optical features of the aerosols such

as Angstrom's exponent ∝ or the signal scattering albedo. In other words, we

can say that the model includes its own aerosol model.

Table (4-3) presents these values, where Fc is forward scattering, ∝ is

Angstrom's exponent, g is aerosol asymmetry factor, w0 is aerosol signal

scattering albedo, w0.4 is signal scattering albedo at 0.4μm, w1is wavelength

variation factor and ρ is the ground albedo.

Table (4-3): values for the characteristic parameter of the model TUV 4.4

Fc α G ω 0 ω 0.4 ω ρ

0.81 1.14 0.65 0.57 0.945 0.095 0.15

TUV 4.4 Model Evaluation This simple parametric model computes broadband transmittance for the

different atmospheric extinction process.

The use of this transmittance allows the computation of the direct beam

component and diffuse component, and the global irradiance is obtained by a

combination of the horizontal projected direct and diffuse irradiance.

The model was evaluated at Baghdad city. Table (4-4) shows the results

obtained including correlation coefficient r2, slope b, and intercept a, of the

linear regression of UV global irradiance estimated versus measurement data.

The model performance has been evaluated about its predictive capability

using mean bias deviation (MBD) and root mean square deviation (RMSD)


32

both as percentage of the mean experimented values. These statistics allow

the detection of both the differences between experimented data and model

estimates. These statistical indicators are defined by:

∑ (4.6)

∑.

(4.7)

In which and are the estimated and measured values

respectively, and N is the number of the data.

From the Table (4-4), show that the results are satisfactory; the overall

performance is rather good with a slight over estimation approximately close

to 5% and RMSD close to 16%.

Table (4-4): Statically results concerning TUV 4.4 model behavior

Locality a B r2 MBD% RMSD%

Baghdad 0.815 0.968 0.87 4.8 15.6

Figure (4.1): shows the scatter plot of estimated versus measured value. The

points rather become near to the prefect fir line:

(r2 = 0.87, A= 0.815, B = 0.968)


33

Figure.(4.1): Comparision of UV global irradiance based on measured and calculated using TUV4.4 model.

Bosca' et al.,(1997) have proposed a modified version of the TVU 4.4 code,

among other innovations; these authors propose the implementation of the

TUV 4.4 code. In this way, one can expect the rest of the aerosol model

parameters corresponding to MRC and MR are close to those fixed in original

version of TUV 4.4 code.

Table (4-5): considering the modification suggested by Bosca etal., [1997].

The general underestimation is obtained when TUV 4.4 used with the aerosol

models included in table (4-6).

MODEL FC W0 W0.4 ∝ g

MCR 0.78 0.94 0.96 1.4 0.60

MR 0.81 0.9 0.95 1.3 0.65

RU 0.84 0.81 0.64 1.3 0.70

PU 0.87 0.59 0.74 1.1 0.75


34

Table (4-6): Statistically results concerning TUV 4.4 model behavior with modifications of Bosca et al., [1997] MODEL a b r2 MBD% RMSD%

MCR 0.58 0.96 0.91 -4.1 8.9

MR 0.58 0.96 0.89 -3.8 9.1

RU 0.58 0.96 0.92 -8.9 13.0

MU 0.58 0.96 0.94 -9.9 14.5

PU 0.58 0.95 0.90 -12.9 18.1

4.5 SMARTS 2.9.5 Model Evaluation As mentioned , this model permits the choice among eleven aerosol models.

Three models correspond to the standard radiation atmosphere (WMO, 1986).

Four models depending on relative humidity have been proposed by Shettle

and Fen, (1979), and two models have been proposed by Braslau and Dave,

(1973). And finally, two models deal with Desert conditions and sand storms.

This code requires as input parameters such as the local geographical

parameters (site's latitude and altitude). The code permits the introduction of

ground meteorological date, although it allows the choice of ten different

Atmospheric reference if this information is not available to the user using a

set of aerosol models that have been described in table (4-5). The models

available are MRC (maritime – rural - clear), MR (Mean Rural), RU (Rural -

Urban), MU (Mean Urban) and PU (Polluted Urban).

Utrillas et al., (1998) have checked the complete modified version of this

model with spectral data.

In our study we have considered the convenience of introducing additional

flexibility to the SMARTS2.9.5 code, allowing the selection among different

aerosol models. Thus the aerosol models described by Bosca' et al., (1997)

have been included as possible choice in the code.


35

Table (4-6): shows the results obtained by TUV 4.4 code when run with the

different aerosol model. All models shows under estimate with MBD

oscillating between 4.1 and 12.9% and RMSD ranging between 8.9 and

18.1%. The worst results correspond to the polluted urban model. On the

other hand, the Maritime – Rural – Clear model and Mean – Rural provide

similar results with MBD close to 4% these results are worse than those

obtained by the built – in aerosol model included in original code.

The code calculates the total NO2 absorption, without distinction between the

tropospheric and stratospheric contributions. The total column abundance of

NO2 is calculated with a correction for reference atmosphere, which is by

default U.S.A the perceptible water can be determined by different methods,

being possible to use climatological averages or empirical equations from

surface data of temperature and humidity, we have used this last method.

We have evaluated SMARTS 2.9.5 at Baghdad using the different aerosol

models.

Table (4-7): Statistically results concerning SMARTS 2.9.5 model behavior with different aerosol models

MODEL A b r2 MBD% RMSD%

SURBAN 0.89 0.86 0.79 +7.3 17

URBAN 0.88 0.99 0.91 +3.6 16.1

RURL 0.12 0.97 0.82 +6.6 18.5

Maritime 0.55 0.92 0.67 +24.6 33.9

Tropospheric 0.93 0.98 0.84 +9.4 19.8

Table (4-7) through a graphic analysis estimated versus measured data, We

have detected a noticeable overestimation for all the aerosol models,

including the urban aerosol models. The last model shows the lowest over

estimation, about 3.6% as a general feature, all the models present that differ

in a ratio of 13% with a range (0.86-0.99), with the urban model having the


36

best fir line. The lowest RMSD correspond to the urban model, thus, we may

conclude that SAMARTS 2.9.5 provides estimations of the solar global

ultraviolet radiation with systematic deviation, within the experimental error,

if the urban aerosol model are selected.

Figure.(4.2): Comparision of UV global irradiance based on measured and calculated using SMARTS2.9.5 model.

Figure (4.2) shows the scatter plot of the estimated versus measured values

for the urban aerosol model. The spread of the points around the perfect fit

line 1:1 is accordance with t

he RMSD and MBD values shown in table (7-4). In our study of

SMARTS2.9.5 model, a separate analysis concerning the model has been

performed. The analysis indicates that there is a correlation indicates that

there is a correlation of the bias with aerosol load. In the case of low aerosol

load, the model shows a slight overestimation as the aerosol load increases,

the overestimation became larger.


37

4.6 Sensitivity Studies and Atmospheric Parameters Impact on Spectral Ultraviolet

4.6.1 Effect of Solar Zenith Angle The influence of solar zenith angle on direct irradiance was investigated by

running the SMARTS 2.9.5 model using the following input parameters;

surface albedo was set 0.1, ozone column was set at 300 DU and the day of

the year was set as 1. The varied parameter in this section is solar zenith angle

which is changed from 0.1° to 80.1° degree with an interval of 10 ° for each

run while the other parameters (albedo, ozone column, day of the year) were

kept constant at this stage; aerosols were not introduced into the model .The

US. Standard atmosphere is used in the model .The results of these studies are

shown in figure (4.3).

Figure(4.3): The variation of direct irradiance with wavelength at diffrent solar zenith angles in the absence of aerosol.


38

Figure (4.3) clarifies that the direct irradiance varies with wavelength in

different values of solar zenith angles. The direct irradiance decreases with

the increase of solar zenith angle . The irradiance on a horizontal surface is Ib

cos (4.8)

Where In is irradiance on the horizontal surface and is the solar zenith

angle [Iqbal , 1983]. So as the solar zenith angle increases the irradiance on

horizontal surface decreases. At solar zenith angle of 0.1°, the irradiance has a

value around 87.8 m w/m² for the wavelength between (280-400).

In the wavelength range between (280-300)nm the irradiance ranged between

(3.2×10-14 to 6.5 m w/m²).The irradiance with solar zenith angle 60° increases

with wavelength from around zero at wavelength of 280 nm to 325 mw/m² at

wavelength of 400 nm. The influence of solar zenith angle on direct

irradiance was studied again using the same parameters used before but in this

stage aerosols were introduced into the model (using Urban aerosol model)

and the results of this sensitivity studies are shown in figure (4.2).

Figure (4.4): The variation of direct irradiance with wavelength at different solar zenith angle in the presents of aerosols.


39

The direct irradiance decrease as the solar zenith angle increases but the direct

irradiance In figure (4.2) as compared to figure (4.1) results is reduced about

17% for the same solar zenith angle and this is due to scattering by aerosols.

The irradiance generally increases with all wavelengths from around zero at

the wavelength of 280 nm to 269 m w/m² at wavelength of 400 nm.

4.6.2 Effect of Albedo The influence of surface albedo on global irradiance was studied by running

the SMARTS 2.9.5 model using the following input parameters; solar zenith

angle was set at 60, ozone column was set at 300 DU and the day of the year

was set at 1. The albedo was changed from 0.0 to 1.0 with interval of 0.1

whilst the other parameters (solar zenith angle, ozone column, day of the

year) were kept constant and at this stage aerosol was not introduced into the

model. The U.S. Standard atmosphere is used in the model .The result of

these studies is shown in Figure (4.5) which shows how the global irradiance

varies with wavelength at different values of the surface albedo.

The global irradiance increases as the surface albedo increases. This is due to

the fact that as the albedo increases, more solar radiation is reflected from the

surface of the ground into space. It should be clear that, when talking about

albedo, we are referring to diffuse radiation; this means that for an ideal

diffuser surface the radiation reflected is independent from the angle of

incidence. The direct beam component of the global irradiance independent of

the albedo. The global irradiance at a solar zenith angle has a value of about

484 mW/m2nm at a wavelength of 330 nm when the albedo is 1.0 but it

decreases to about 276 mW/m2nm at the same wavelength when the albedo is

zero. The irradiance generally decreases from its peak at 330 nm to about zero

at 280 nm.


40

Figure(4.5):The variation of global irradiance with wavelength at different surface albedo in the absence of aerosol.

The influence of surface albedo on global irradiance was studied again using

the same parameters as before but this time aerosol was introduced into the

model. The same type of aerosols were introduced as in the sensitivity studies

of the effect of solar zenith angle and the result is shown in Figure (4.4)

The irradiance increases as the albedo increases but the irradiance as

compared to the irradiance in Figure (4.6) is significantly reduced due to the

scattering of the radiation by aerosol. The peak value at 330 nm is 209

mW/m2nm whereas it was 484 mW/m2nm in the absence of aerosols.


41

Figure(4.6):the variation of global irradiance with wavelength at diffrent surface albedo in the presents of aerosols.

4.6.3 Effect of Altitude The impact of altitude on global irradiance was studied by running the

SMARTS2.9.5 model using the following input parameters; surface albedo

was set at 0.1, ozone column was set at 300 DU, solar zenith angle was set at

60.1 degrees. The altitude was however changed from 0 to 16 km with an

interval of 2 km whereas the other parameters (albedo, solar zenith angle,

ozone column) were kept constant, and at this stage aerosol was not

introduced into the model. The U.S. Standard atmosphere is used in the

model. The result of these studies is shown in Figure (4.7).


42

Figure(4.7):the variation of global irradiance with wavelength at diffrent altitudes with absence of aerosols

This shows how the global irradiance varies with wavelength at different

altitude. The irradiance generally increases with altitude. The irradiance on

the ground increases from 9.56×10-19 mW/m2nm at a wavelength of 280 nm to

357 mW/m2nm at a wavelength of 329.5 nm. From 330 nm to 350 nm the

irradiance is close to 328 mW/m2nm but there are sharp falls at 337 nm (247

mW/m2nm) and at 344.5 nm (267mW/m2nm). At an altitude of 16 km, the

irradiance increases significantly: the irradiance at 329.5 nm is 575.1

mW/m2nm and those at 337 and 344.5 become 385 mW/m2nm and 396.6

mW/m2nm respectively.

The impact of altitude on global irradiance was studied again using the same

Parameters which were used before but this time aerosol was introduced into

the model and the irradiance decreases sharply on the ground as shown in

figure (4.8).


43

Figure(4.8):The variation of global irradiance with wavelength at diffrent

altitudes with presents of aerosols

The peak value at the wavelength of 377 nm falls to 612 mW/m2nm and the

irradiance in the wavelength region of 320 to 350 nm falls to about 266

mW/m2nm. Also the irradiance at the wavelengths of 337 nm and 344.5 nm

are respectively 200 mW/m2nm and 215 mW/m2nm. The irradiance at the

height below 4 km decreases clearly and this is due to the high loading of

aerosols in region between altitude (4 to 6 km). At a wavelength 329.5 nm the

irradiance falls to 254 mW/m2nm from 357 mW/m2nm (in the absence of

aerosol) at earth surface. At a height of 6 km the irradiance falls to 413

mW/m2nm from 488 mW/ m2nm (in the absence of aerosol) at a wavelength

of 329.5 nm. The irradiance from the height of 8 km to 16 km is not so much

reduced and this suggests that most of the aerosols are located in altitude

ranging from 0 to 6 km and concentrated in range from 4 to 6 km, The

reduction in the irradiance is caused by scattering by aerosols.


44

4.6.4 Effect of Ozone The impact of ozone on global irradiance was studied by running the

SMARTS2.95 model using the following input parameters; surface albedo

was set at 0.1, solar zenith angle was set at 60 degrees . The ozone column

was however changed from 200 to 400 DU at an interval of 50 DU whilst

the other parameters (albedo, solar zenith angle , day of the year) were kept

constant and at this stage aerosol was not introduced into the model. The

U.S. Standard atmosphere is used in the model. Figure(4-9) shows that

there is a noticeable absorption of global Ultraviolet by ozone with

wavelength ranged between (292-337nm) and also shows a strong

absorption in monochromatic wavelength such as (305,312,318nm)

Figure (4.9):The variation of global irradiance with wavelength at different total ozone column with absence of aerosols.

The influence of ozone on global irradiance was studied again using the same

parameters as before but this time aerosol was introduced into the model. The

same type of aerosols were introduced as in the sensitivity studies of the

effect of solar zenith angle and the result is shown in Figure (4.10). There is a


45

noticeable absorption of ozone starts with wavelength 292 nm and there is

absorption about (14-19%) in this wavelength for every 50 DU(from total

ozone column (200-400) and the effective ozone absorption ranged between

the wavelength (292-337) nm, According to these two stages which are

shown in the figures, we compare the resulted outputs and we notice that the

aerosols reduction is about (16 %) in global irradiance if we considered the

total ozone column is 300 DU.

Figure(4.10):The variation of global irradiance with wavelength at

diffrent total ozone colunm with presents of aerosol. The extinction in each layer (1 km) of the atmosphere (stairs) was studied at a

monochromatic wavelength of 305 nm by running SMARTS 2.9.5 model

introduced the result of this studies which shows how extinction coefficient at

a monochromatic wavelength of 305 nm changes with altitude. The extinction

coefficient increases sharply at an altitude of 30 km to 21 km (that is 0.033 to

0.099),this suggests that there is high ozone concentration in this profile

region . The increase in extinction below 7 km to 4 km (that is 0.147 to 0.334)

is due Rayleigh scattering. The extinction coefficient increases sharply at an


46

altitude of 3 km and below from 0.334 to 0.493 at an altitude of 1 km and this

indicates the location of high loading of the aerosols.

Figure (4.11):The variation of exticntion coefficinet at a monochromatic

wavelength of 305 nm with altitude

4.7 Test of Diurnal Behavior of SMARTS Output in UV-Range. The accuracy of SMARTS model was tested by comparing model out with

clear sky measured data recorded by Epply ultraviolet Radiometer used in Al-

Jadiriyah location Energy and Environmental research center (Lat 33.34 N,

Long 44.45 E, 34 m a.s.l).

Nearly clear sky condition was observed on 10 January, 11 February, 23

March, 23 June, and 8 July 1998 which is shown in figures (12.4) a, b, c, d

and e. Total ozone column obtained from the data base of TOMS, standard

atmosphere meteorological profile was employed by using the standard

humidity profile, because of the large portion of soil proportion and soot

presence in the air of the town.


47

Urban aerosol type considered, there is no aerosols optical depth

measurement, so averaged conditions are assumed, Global UV irradiance is

measured every hour.

All input parameters were assumed to be constant over the day. As can be

seen in figures (4.12) a, b, c, d and e the values of SMARTS model outputs

are higher than the measured especially with lower solar zenith angle, This

different is the results of uncertainty of the model input parameters.

The main source of these differences is boundary layer aerosol treatment that

has noticeable influence on model output.

There is a clear overestimation ranged between (4.47-6.4%) partially results

from the extinction of UV radiation by clouds the sky way not completely

cloud free i.e. the cloudiness is not an input parameter of SMARTS model

besides the lack of necessary aerosol measurement estimates give confidence

that this model provides a satisfactory presentation of the dentinal behavior of

Global UV reach earth surface.

It was found that the model calculations are slightly higher than the

measurements, and the main source of the difference is lack of necessary

measurement that can provide better input atmospheric conditions.


48

Figure (4.12): Comparison of diurnal behavior of UV global based on measurements and

calculations using SMARTS2.9.5 model presented on sub figures (a, b, c, d and e) in 10 January, 11 February,26 Mach, 23 June, 8 Julay1998 .


49

4.8 Ozone Influence on UV-B UV-B radiation values used in this part of the thesis were obtained using

SMARTS 2.9.5 model which calculate the board band radiation with internal

of 280-315 nm.

That corresponds exactly to the UV-B range we have calculated the UV-B

values for a fixed solar zenith angle with different days of the year 2002.

The daily ozone data used in this thesis in Dobson units (DU), were obtained

through TOMS/NASA which is installed on board band of NASA's Earth

probe satellite which has been measuring the total ozone column since 1996

in direct way, through mapping of ultraviolet light emitted by the sun and

scattered by earth's atmosphere back towards the satellite [LONDON, 1985;

NASA/TOMAS, 2000]. After collecting the daily ozone data and calculate

UV-B radiation intensities for each solar zenith (20° - 70°) with five degrees

interval angle with clear sky conditions, the direct comparisons between the

calculations were performed and presented in figure (4.13).

Figure(4.13): UV-B irradiance calculations as a function of Total Ozone


50

The correlation coefficients were calculated by using percentage of ozone

(DU) and UV-B (w/m2) in relation to the average of these parameters in the

analyzed group of the data obtained for each solar zenith angle.

Figure (4.13) and figure (4.14) present parentage variation of UV-B irradiance

and total ozone column for 50˚solar zenith angle which were calculated by

employing the following relations:

∆ (4.9)

∆ (4.10)

In these expressions∆ , and ∆ represent respectively, the deviation in

relation to ozone and UV-B radiation averages in percentage.

is TOMS daily data in Dobson unit, and UV-B in w/m2 for each fixed

solar zenith angle.

For better visualization of anticorrelation behavior, we chose the S.Z.A (50°)

(with A = 0.029 and r = 0.962) a linear fit (Y= A+B*X) adjustment which

was applied for more data points (n=100) for (50°) solar zenith angle, It was

determined that the slope of the line (B) and the point in the line are crossed

by the correlation coefficients (R),these values are presented in the legend of

figure (4.14).

It can be observed from the figure (4.14), that the function fit is a line

crossing closely to origin that the (A) value are very small and this mean that

A is near to zero i.e. (Y≈B×X), thus the (B) values correspond to an

estimation of the increase in UV-B percentage relative to ozone reduction of

about 1.1%.


51

It was also observed that the calculated correlation coefficients presented high

values resulting in R=-0.960 (R2 = 0.92) and lowest R= 0.64 (R2=0.795) for

solar zenith angle 50° and 70° respectively.

Figure(4.14):Correlation for 50˚ solar zenith angle for selected Clear days of the year 2002.

Fig (4.15) shows the total ozone column and UV-B radiation seasoned

behavior for the solar zenith angle 50° which achieved the heights ant

correlation coefficient (-0.96), one can clearly recognize the opposite

behavior between the plotted data. For instance, a very high ozone value equal

to 358 DU is corresponded to a very low UV-B radiation value equal to 0.435

w/m2, this mean so that the highest value of ozone correspond to the lowest

value of UV-B with clear sky conditions on 23 March 2002.


52

Figure(4.15):Total Ozone Colunm and UV-B irradiance seasonal behavior for 50˚ solar zenith angel for selected cear days for year 2002.

Figure(4.16): Seasonal behavior of Ozone and UV-B percentage variation xin realtion to its average for 50˚ solar zenith angel for selected

clear days for year 2002


53

Examining the above statistic analyses, we can expect that the increase of

ozone value is about 1.17% leads to decreasing UV-B values about 1% for

50° solar zenith angle.

Each point group and linear fit corresponds to an analyzed solar zenith angle.

The value, in parenthesis beside each S.Z.A is representing the percentage

variation caused in UV-B for ozone variation of about 1.27%. These values

were determined using the general slope (B) obtained by each fixed S.Z.A

which is shown in table (4-8).

In order to study ozone and UV-B correlations of other factors, a filtering

method was employed to remove the cloud effect (using data obtained only in

clear sky conditions) and geometrical effect of the solar angle (using fixed

solar zenith angle).

With the selection of clear sky conditions data group, considerable

improvements of the correlation coefficients (in relation to those obtained by

Basher et al., (1994) who reported a coefficients between (-0.93) and (-0.66)

for UV-B measurements in clear sky condition and ozone measured by

satellite) are observed

There is a large agreement with anticorrelation founded by Kirchnoff et.al .,

(1997) which achieved anticorrelation obtained by Wang et.al (2002) was

(-0.88) and the decrease of total ozone about 1% enhance UV-B about 1.23%

for 50° solar zenith angle whereas in our study the anticorrelation was (-0.96)

and the decreasing of 1% of total column will produce about 1.55% UV-B

enhancement for the same solar zenith angle.

Decreases in total ozone column values can produce considerable UV-B

enhancements.

This section calculates one percent of the ozone decreasing produced increase

of UV-B between (0.76-1.78 %) relative to the used solar zenith angle.


54

Table (4-8) Correlation coefficient (R) and their confidence levels (CL), A and B values for linear fit (y=A+Bx) for each solar zenith angle.

S.Z.A A B R CL%

20 0.26 -0.76 -0.902 99

25 0.23 -0.91 -0.880 99

30 0.41 -1.04 -0.903 99

35 0.69 -1.17 -0.930 99

40 0.46 -1.57 -0.910 99

45 0.64 -1.52 -0.910 99

50 0.029 -1.096 -0.9602 99

55 0.11 -1.78 -0.841 99

60 0.7 -1.34 -0.824 99

65 0.170 -1.51 -0.803 99

70 1.7 -1.76 -0.795 99

4.9 Impact of Aerosols and Clouds on Ground Base Ultraviolet Measurement and the Seasonal Behavior of UV-B with Seasonal Behavior of Ozone.

The measurement employed in this part is taken from the ultraviolet sensor

maintained above the automatic weather station which is illustrated of the

roof the Department of Atmospheric Sciences building. The UV sensor

measures the UV-doses every 15 minutes during the day.

Radiative transfer models are important complement to measurement,

Models are also an essential aid to identify the causes of observed UV-

changes to carry out sensitivity studies, and ultimately to predict future UV

environments under different atmospheric conditions.

Ultraviolet – B radiation (UV-B) is monitored for Baghdad city (33 34' N,

44, 45' E, 34 meters above sea level) using meteor data, the measurements of

UV-B irradiance were collected between 1/1/2002 and 31/12/2002, the

maximum UV-B irradiance measured was 2.94 w/m2. In this section, we will


55

employ these measurements to investigate the seasoned variation of UV-B

radiation to assess its response to ozone values.

The anticorrelation between total ozone column and UV-B radiation is well

established, Besides the sectional variation of the geometrical path length of

solar radiation through the atmosphere plays a dominate role, the objective of

this section is to focus light on the Global UV radiation levels reaching the

earth surface. The Global UV measurements employed in this section were

compared with radiative transfer model (SMARTS 2.9.5) calculation. The

input parameters for this radiative transfer model are date, time ozone

column, and surface albedo, for our calculations, default aerosols model were

used due to the lack of these data in Baghdad city.

The daily total column ozone content between 1/1/2002 to 31/12/2002 over

Baghdad city is measured by TOMS (Total Ozone Mapping Spectrometer)

which shown in figure (4.17).

Figure (4.17): The annual course of Total Ozone Column based on TOMS data base over Baghdad city in the year 2002.


56

The line is the best – fit linear trend of the mean value for this year is (296.2)

DU. The maximum value are usually recorded between April and May and

the minimum are between August and October.

The annual course of UV-B in Baghdad city for the year 2002 is shown in

figure (4.18). We presents UV-B irradiance at solar noon for all the days that

we could carry out the measurements the maximum and minimum values of

UV-B radiation are recorded with (2.94) w/m2 and (0.19) w/m2 in 19 August

and in 16 April respectively and this corresponds to the minimum and

maximum records of ozone (401) DU and (260) DU in 17 April and 27

October and this establish a good anticorrelation of UV-B with ozone values.

Figure(4.18): The annual course of UVB irradiance based on Meteor data base for the year 2002.

And for more virtualization we presents figure (4.19) which shows the clear

effect of ozone on UVB radiation behind the insignificant effect on Global

UV radiation if compared with effective on UVB radiation.


57

Figure(4.19):The anual cource of Global UV,UVB irradiance and Total Ozone Column for the year 2002.

In this part, we investigated the measurement of UV-sensor which is

maintained above the weather station in Al-Mustansiriyah University, in order

to study the Impact of aerosols and clouds on Global UV reaching earth

surface. But firstly we will make a test for the UV-sensor. We compare the

measurement with model calculation as shown in figure (4.20).

The results show a good agreement with the UV-sensor with slight over

estimation (about 5.4%) which can be considered in reduction calculation.


58

Figure(4.20):Comparison between measured and calculated durinal variation of global UV radiation on (clear day) 3 June 2007.

Figure(4.21):Comparison between measured and calculated durinal variation of global UV radiation on(high aerosols loading day) 28 June 2007.


59

Unfortunately, aerosols in Baghdad city have not been characterized yet,

making it very difficult draw more than qualitative conclusions. Preliminary

analysis of Global UV-Radiation of consecutive days with high aerosols an

important decrease in UV redaction.

The effect of clouds is focused on Global themselves because they depend on

many factors such as cloud type, thickness, cloud water content, droplet

number density conditions usually changes in short time making it very

difficult to analyze and predict its effect, in order to capture the rapid

variation in irradiance.

Figure(4.22):Comparison between meatured and calculated durinal variation of global UV radiation on 6 June 2007.

Different effects can be noticed in figure (4.22), one of these effects is the

decrease of intensity with cloudless condition days.

The decrease is the most common one and it can be as large as 38% for

heavily cloudy days. The increase due to case called broken cloud effect is


60

produced on practically cloudy when direct light is present and the diffuse sun

light is increased by scattering on the sites of white clouds.

4.10 Impact of Cloud Cover on Global UV Irradiance. In this section six months of continuous measurements of UV irradiance

recorded at Baghdad city, were combined with synoptic cloud observations in

order to establish a relative influence of cloud cover on UV irradiance. At a specific site, the main factor causing variation in solar elevation angle.

The observed daily and yearly variations are dominated by this factor.

The total ozone and clouds cover are of second- order importance for the

variation of the radiative flux. Atmospheric aerosols also affect the UV

irradiance, But their influence is small relative to cloud cover (lorente et

al.,1996; Diaz et al., 2001; wenny et at., 2001). A many of these factors

influencing the UV irradiance, cloud cover present a high temporal and spatial

variability.

It is certain that clouds can cause large year to year variability in UV radiation

and therefore possibility play an important role in determining long term

trends (Seckmeyer et al.,1998).

For the cloud effect, it is necessary to have knowledge of clouds optical

thickness and drop size distributions.

In this part of the thesis, we have examined the effect of cloud on UV

irradiance using the information routinely recorded by radiometric station in

Al-Jadiriyah location with concurrent fractional cloud cover in octas. This

usually recorded on a three hourly basis.

This section was carried out at Baghdad during the period October 1994-

March 1995. After analyzing variations in the UV irradiance due to

presence of cloud. We have studied the effect of cloud on UV irradiance

by considering a cloud modification factor, defined as the ratio between


61

the UV measurement and corresponding clear sky UV irradiance that

would be calculated for the same time period and atmospheric condition.

In our case, we used a model which tested previously to account for UV

irradiance under clear sky conditions. Thus, this model allows estimation

of cloudless UV irradiance.

The UV irradiance data were classified according to cloud cover

observations. Additionally, we split the data in several sun elevation

Categories. Four categories have been considered characterized by sun

elevation angles, θ(60˚< θ1,40˚< θ2 <60˚, 20˚< θ3 <40˚ and 10˚< θ4 <20˚)

for each sun elevation and cloud cover categories, we computed the mean

and standard deviation of UV irradiance Fig (4.22).Presents the

dependence of UV irradiance on cloudiness for the different sun elevation

ranges.

Figure(4.23):Ultraviolet global irradiance vs cloud cover for diffrent solar elevation angles.

The cloud effect is clear evident during high cloud cover but negligible for

fractional cloud cover below 3 octas suggesting that, for these cloud covers,


62

clouds tend to be located out of the line between the sun and sensor, it also

can be noticed in Fig (4.23). That the combination of high solar elevations

and overcast skies yields similar results to that associated with low solar

elevation and cloudless skies. The performance of UV irradiance under

cloudily conditions is similar to that followed by the solar irradiance in other

spectral rages (kasten and czeplak., 1980 ; alados et al ., 2000). It could be

useful to analyze the performance of a dimensionless ratio like that obtained

as the ratio of UV irradiance to the total solar radiation, G. total solar

irradiance. The ration UV/G provides insight into the relative importance of

UV irradiance of total solar irradiance at the surface. This ratio has been

studied by different authors (Martinez- Lorenzo et al ., 1994 ; Foyo-Monreno

et al., 1998 ; canda et al ., 2000), figure(4.24) shows the dependence of UV/G

on cloud cover for the same sun elevation angel categories considered in

previous analysis of UV irradiance.

A first result, evident from figure (4.24) is that the ratio UV/G increases with

cloud cover, and this increase is more evident for cloud cover greater than 4

octas. This means that there are some differences in the effect of cloud on

total solar irradiance and UV irradiance. The increase demonstrates the

spectral dependence of the cloud radiative extinction.

In this sense, a greater absorption in the near infrared region than in shorter

wavelength (Lenoble, 1993) causes an enhancement of the UV range relative

to the total solar spectrum (Ambach et al., 1991). On other hand, although the

differences are rather small, it seems that for higher solar elevations UV/G

presents greater values than for lower solar elevations, at least for cloudless

and partially cloudless conditions. The increase of UV/G with cloud cover is

greater for lower solar elevations and thus for over cast conditions the mean

UV/G value does not depend on the solar elevation analysis.


63

Figure(4.24):Rati of global ultraviolet irradiance to total solar irradiance

UV/G vs cloud cover for diffrent solar elevation angles.

To study this relationship further we have analyzed the index Ktuv, defined as

the ratio between the UV irradiance reaching the surface level and the

corresponding extraterrestrial flux UVext (Martinz – Lozano et al., 1994). That

is:

(4.9)

Where: UVext is the UV extraterrestrial solar radiation on a horizontal surface

given by:

(4-10)

And is the solar elevation and the sun-earth distance in astronomical

units.

The solar constant for UV, ISCUV, has been taken as 78 w/m2 from spectral

values given by Lenbole, (1993).

Figure (4-25) shows the dependence of UV/G ratio and Kt UV with cloud

coverage for data registered around noon and demonstrates the opposite

trends of this ratio as function of cloudless conditions, the Kt UV index had a


64

value of about 0.45 and the UV/G ratio was close to 4%. The different trends

for this ratio: as the cloud cover increased lead to an overcast value of about

5% for UV/G while the reduced value of Kt UV index was close to 0.2.

Figure(4.25):Ratio of global ultraviolet irradiance to total solar irradianc UV/G and hemispherical ultraviolet transmittance Ktuv, vs cloud cover for diffrent solar elevation angles.

Since the global irradiance (Ultraviolet or solar total radiation) varies widely

under different sky conditions, it's convenient to normalize the global

irradiance to minimize variability and maximize the generality of the results.

For this reason, we have analyzed the performance of UV global irradiance

normalized to the value under cloudless sky.

This parameter was defined as , where the subscript (0) refers to

cloudless sky. UV0 can be estimated by application of any simple radiative

transfer model (SMARTS 2.9.5) (Gueymard, 2005). We considered the cases

with zero octas cloud cover. We separated these data in optical air mass

categories, for each category the mean and standard deviation of the UV


65

radiation were computed. The empirical function describing UV0 is obtained

by a weighted fit of this mean values (Figure 4.26).

Figure(4.26):UV global irradiance vs optical air mass.

This UV0 functions has been used to obtain the corresponding FUV index that

can be considered as a cloud modification factor. Figure (4. 27) presents the

performance of this global UV cloud modification factor, as a function of

cloud coverage for different sun elevation angle ranges considered in this

study.

It can be seen that the behavior of FUV is similar for the different ranges of

solar elevations. Similar results were found by Josefsson and Landelius .,

(2000). This can be explained as a result of the reflection enhancement under

partial cloud cover conditions when geometric conditions are most favorable

for the reflection of UV radiation from cloud edges or between base of cloud

and the ground surface. For partial cloud cover, this factor presents greater

values when solar elevation is high.


66

Figure(4.27):Ultraviolet cloud modification factor ,FUV vs cloud cover for different solar elevation angles.

Under over cast conditions the results obtained for different sun elevation

angle ranges (0.48-0.56) according to solar elevations. Grant and Hersler .,

[2000] analyzed the UVB irradiance under variable cloud conditions and

found a similar trend with an overcast of 0.65, on other hand, Seckmeyer et al

., [1996] obtained a cloud modification factor that varies between 0.45 in the

UVA range and 0.6 in the UVB range.

This difference can be explained by the wavelength dependence of radiation

scattering with the cloud, by redistribution of UV radiation due to the cloud.

The standard deviations of the cloud modification factor in table (4-9), FUV,

increase with increasing of cloudiness, possibly as a result of variation in

cloud opacity. In fact cloud cover alone does not contain explicit information

on the optical transmission of clouds. When the sky is only partly cloudily the

irradiance values will vary depending on whether the sun in the clear or

cloudily portion of sky domes. The nonlinear dependence of FUV with

cloudiness is largely due to the relatively greater value for intermediate


67

cloudiness. Which can be due to reflection from the side of clouds that locally

enhanced the radiation levels?

Table (4-9) Statistical parameters for cloud modification factor for different

cloud covers.

Cloud

Cover

FUV mean

θ1

FUVsd

θ1

FUV mean

θ2

FUVsd

θ2

FUV mean

θ3

FUVsd

θ3

FUV mean

θ4

FUVsd

Θ4

0 1.14 0.086 1.07 0.081 1.03 0.089 1.02 0.11

1 1.16 0.067 1.08 0.064 1.04 0.086 1.01 0.9

2 1.12 0.072 1.05 0.091 1.01 0.120 0.99 0.12

3 1.13 0.088 1.04 0.013 0.97 0.130 0.98 0.132

4 1.04 0.190 1.02 0.132 0.92 0.131 0.96 0.135

5 1.02 0.166 1.01 0.128 0.87 0.160 0.94 0.141

6 0.9 0.163 0.92 0.215 0.77 0.196 0.96 0.143

7 0.87 0.189 0.73 0.221 0.71 0.218 0.74 0.223

8 0.48 0.280 0.52 0.219 0.53 0.230 0.65 0.22

FUV mean: mean values of FUV, FUVsd: corresponding standard deviations

As cloud cover increase beyond 4 or 5 octos, there is a greater chance that the

solar disk will be obscured by clouds and thus the attenuation of UV

irradiance increase.

Inspection of Figure (4.25) and Figure (4.27) reveals the similarity in the

dependence of Kt UV and FUV on cloud cover. This shows the predominance

of the cloud effect on UV radiation, evaluated through, FUV, over the whole

atmospheric effect, evaluated by means of Kt UV.

It is possible to compute a cloud modification factor for total solar irradiance,

FG = G/G0. In order to study the different influences by clouds on both

radiative fluxes in figure (4.28) we show the relation between dimensionless

factors (FUV = UV/UV0 and FG = G/G0).

A procedure similar to that followed in the evaluation of UV0 has been

considered in the estimation of G0. After an extensive examination of various


68

curves fitting option, the following functional dependence was found to be the

most appropriate:

FUV= - 0.016 + 1.106 FG – 0.079 FG2 – 0.05 FG

3

For the above relation (R= 0.93 with standard error of estimate =0.09). There

is evident departure from the line 1:1 that represent coincident factors, i.e., the

clouds does not transmit equally the UV global solar irradiance.

Figure(4.28): Ultraviolet cloud modification factor ,FUV vs total Global cloud modification factor FG.

Figure (4.28) shows that the total global irradiance suffers a proportionally

reduction than the UV global irradiance. A possible explanation for values,

could be the reflection of solar reflection of solar radiation at the edges of

Cumulus clouds (Mims and Frederich ., 1994) or very thin cirrus clouds that

act as UV green house (Madronich , 1987). Other authors have obtained

similar results in their analysis of biologically effective UV radiation; this is

the case Bordewirk et al .,(1995) and Matthijsen et al ., (2000) analyzing data

from the Netherlands.


69

Bodeker and Mckenzie ., (1996) also obtained similar relationship between

the cloud modification factors corresponding to the erythmal UV irradiance

and global irradiance with measurements made at Lauder (New Zealand).

Figure (4.29) shows the relation between the Ultraviolet cloud modification

factor FUV and the global cloud modification factor FG as a function of cloud

cover. In accordance with figure (4.24), clouds do not decrease UV radiation

as much as global radiation, a result also shown by Josefsson and Landelius .,

(2000)

Figure(4.29):Ratio of UV global cloud modification factor FUV to total global cloud modification factor FG vs cloud cover.

Chapter five Conclusion and Suggestions

70

Chapter Five Conclusion and Suggestion

5.1 Conclusion 1. There is a noticeable attenuation in direct irradiance when the solar zenith

angle becomes larger than 50˚ and this is due to the thickness of optical path

through the atmosphere which becomes larger for the zenith angle which is

larger than 50˚.

2. There is a clear impact of ozone variation on global irradiance reaching

earth surface especially within the wavelength ranged between (292-337nm)

and there is a strong absorption in monochromatic wavelength such as :

(305,312,and 318nm) and the effect of aerosols in ozone sensitivity

experiment reduces the global ultraviolet irradiance about (16%) and there is

an absorption about (14- 19%) for each 50 DU with (200-400DU) ozone

variation range.

3. The extinction of the atmosphere for monochromatic wavelength of 305 nm

has the largest value (0.33-0.49) for corresponding the altitude which is

ranged between (4-1km) and this is an indicator of high aerosols loading

existence corresponds to this altitude profile.

4. There are a good agreement between the calculated UV doses by

SMARTS2.9.5 and the measured UV doses with correlation coefficient (0.91)

and mean bias deviation (3.6%) and root mean bias deviation (16.1%), this

result also shows a good agreement with the results obtained from the diurnal

test of the SMARTS2.9.5 output in UV range which presents an over

estimation ranged between (4.47-6.4) for selected clear days of the year 1998.

There is an opposite behavior of UVB with ozone i.e. 1% decreasing of ozone

which can produce about 1.1% UVB radiation enhancement.


71

5. From satellite observation (TOMS and Meteosat) we can clearly notice that

the maximum value of UVB radiation (2.94 w/m2) corresponds the minimum

value of ozone (260 DU) and the minimum value of UVB radiation (0.19

w/m2) correspond the maximum value of ozone (401 DU) in 27 October and

17 April respectively and this establish a strong anitcorrelation of UVB with

ozone.

6.There is a clear impact of ozone on UVB radiation beside the insignificant

effect on global UV if compared with effective UVB radiation and this result

is obtained because of the UVB radiation is a part of global Ultraviolet as a

portion which does not exceed than (8.3%) in the best cases.

7. Aerosols can produce extinction about (24-32%) on diurnal behavior of

global ultraviolet.

8. Clouds can attenuate the global ultraviolet by (38%) for heavily cloudy

days.

9. In the final parts of chapter four we investigated the effect of cloudiness on

global UV irradiance intensity correspond with different solar elevation.

The effect of clouds begins with solar zenith angle greater than 20 and

cloudiness correspond with 4 or 5 octas.

10. The UV irradiance with 4 octas cloud cover conditions cannot be affected

because the cloud cover in this amount means separated clouds in the sky.

5.2 Suggestion and Future Works

1. Measure UV index using the UV sensors above Al-Mustansiriyah weather

station and compare it with values estimated by models in order to use these

models in regions that have a shortage of these sensors.

2. Measuring UV radiation using the sensor mounted on Al-Mustansiriyah

Weather Station for several years in order to obtain a relation with ozone data


72

measured by Total Ozone Mapping Spectrometer in order to estimate the

increase in UV doses reaching earth surface and the decrease of the

corresponded ozone values.

3. Installing a number of UV sensors in different regions in IRAQ in order to

create an Ultraviolet atlas for IRAQ.

4. Compare the values of UV dose measured using ground base sensors with

values estimated using Total Ozone Mapping Spectrometer in order to

evaluate the results obtained by this satellite sensors.

5. Study the effect of cloud type on Ultraviolet radiation.

6. Employ the SMARTS2.9.5 model in order to estimate irradiance in visible

and infrared bands.


73

73

References Alados, I., Olma, F.J. FOYO – Moreno .I (2000) Estimation of photo

synthetically active radiation under cloudily conditions. Agricult. Forest

Meteorology. 102,44-50.

Ambach,W., Blumthalar, M., Wendler, G (1991) Comparison of Ultraviolet

radiation at an arctic and an alpine site, solar Energy. 47, 121, - 126.

Andrews,G.D.(,2000) . An Introduction to Atmospheric physics, 61-65.

ASTM. 2000. Standard solar constant and zero air mass solar spectral

irradiance tables. Standard American society for Testing and materials.

Basher, R.E., Xzxeng, S.Nichol ., (1994). Ozone related trends in solar UV-B

series. J. Geophys. Res. 20, 2713-2716.

Bernhard, G., G. Seckmeyer, R.L. Makenzie (2004) Spectral quality control

tools for solar UV measurements, J. Geophys. Res., 103, 28855-28861.

Bird, R.E (1984) A simple solar spectral model for direct normal and diffuse

horizontal irradiance. Solar Energy, 32, 461-471.

Bosca, J.V., J.M. Pinago, J. Canada (1997) Modification of TUV4.4 code

estimation of spectral solar direct irradiation, diffuse and global in proceeding

of VIII congress of proto, Portugal.

Braslau, N., Dave, J.V (1973) Effect of aerosols on the transfer of solar

energy through realistic atmospheric models, J. Meteorological., 30, 601-619.

Canada, G., Pedros, G., Lopez, A., Bosca, J (2000) Influence of the clearness

index for the clearness index for the spectrum and of the relative optical air

mass on UV irradiance for two locations in the Mediterranean area, Valencia

and Cordoba, J. Geophys. 105, 4759-4766.

Ciren, P., Li, Z, Wang (2003) Long-term global earth surface ultraviolet

radiation exposure derived from TOMS satellite measurements. Agriculture

and Forest Meteorology. 120, 51-68.

74

Diaz, j. p., Exposito, F.J., Torres., C.J. Herra (2001) Radiative properties of

aerosols in Saharan dust out breaks using ground based and satellite data, J.

Geophys. Res. Atmos. 106, 18403-18416.

Dubronvsky. M (2000) Analysis of UV-B irradiance measured

simultaneously at two stations in the Czech Republic, J. Geophys. Res, 105,

4907-4913.

Foyo-Moreno, I., vida, J., Alados- Arboledos, L (1998) A simple of all of

weather model to estimate ultraviolet solar radiation (295-385nm),

J.Appl.Meteorol ,38,1020-1026.

Foyo-morrno, I., vida., J., Alados-Arboledos (1998) Ground based

ultraviolet (295-385 nm) and broad bond solar radiation measurements in

south-Eastren Spain. INT. J. climatological, 18, 1389-1400.

Frederick, J, E., Steele, H.D (1995) The transmission of sun light trought

cloudly skies analysis based on standared meteorological information. J.

Appl. Meteorology. 34, 2761-2775.

Frederick, J.E., J.R Sulsser., D.S.Bigelow (2000) Annual and inter annual

behavior of solar ultraviolet irradiance revealed by broad band measurements,

photo chem. photo boil. 72, 488-498.

Fröhlich. C (1981) Spectral distribution of solar irradiance from 25000 nm to

250nm. World Radiation center, Switzer land.

Grant, R.H., Heisler, G.M (2000) Estimation of ultraviolet- B irradiance under

variable cloud conditions. J. Appl. Meteorology, 39, 904-412.

Guarnieri, R. A ( 2004) Ozone and UV-B radiation anticorrelation at fixed

solar zenith angles in southern Brazil. INT, Geophys. 43, 17-22.

Gueymard ,C.,(1998). Turbidity Determination From Broadband Irradiance

measurements, J,Appl.Meteorol,37,414-435.

Gueymard, c., (1993). Development and performance assessment of a clear

sky spectral radiation model, proceeding. 22nd ASES conference. solar., 93,

Washington, DC, American solar Energy society, pp. 433-438.

75

Gueymard, C (1995). SMARTS 2, A simple model of the Atmospheric

Radiative Transfer of sunshine: A logarithms and performance assessment,

Florida, solar Energy center (FSEC),27, 532-538.

Gueymard, C(2003). direct solar transmittance and irradiance predictions

with broadband models. part I: detailed theoretical performance assessment.

Solar Energy, 74, 355-379.

Gueymard, C (2004). solar Radiation & day light models 2nd Edition,

Elsevier.

Gueymard, C (2005). SMARTS code, version 2.9.5, user manual, solar

consulting service, USA.

Herman, J., Bhatia. R.P Mcpetres (1996). Meteor-3 Total Ozone Mapping

Spectrometer (TOMS) Data products User's Guide, NASA Reference

Publications.

Hofgumahaus, A., A. Kraus., M. Mülle (1999). solar actinic flux

spectroradiometer: A tecknique for measuring photolysis frequencies in the

atmosphere, J. APPL. Opt., 38, 4443-4460.

Ilyas, M (1987). Effect of cloudiness on solar ultraviolet radiation reaching

the surface. Atmos. Envirom. 21, 1483-1488.

Iqbal, M (1983). An Introduction to solar Radiation. Academic press. New

York.

Josefsson, W (2004). Ultraviolet measurements in Ncrrköping between 1993-

2003. Report 24. Germany Institute of solar energy.

Josefsson, W., Land elius,T ( 2000). Effect of clouds on UV irradiance. As

estimated from cloud amount, cloud type, precipitation, global radiation and

sunshine duration, J.Geophys. Res. 105, 4927-4935.

Kasten, F., C.Z. eplak, G (1980). Solar and terrestrial radiation dependent on

the amount and type of cloud. Solar Energy, 24, 177-189.

Kirchhoff, V. W., F., zamorano, C. casiccia (1997). UV-B enhancements at

Punta Arenas, Chile. J. photo chem. Photobiol, 38, 174-177.

76

Krzyscin, J.W (2000). Impact of the ozone profile on the surface UV radiation

in Poland, J. Geophy. Res. 105, 5009-5015.

Kuckinke, c., Nunez, M (1999). Cloud transmission estimates of UV

irradiance, Theor. Appl. Climatol. 63, 144-161.

Kudish, A.I., Evseev. E (1997). The analysis of ultraviolet Radiation in the

Dead Sea basin, Int, J. Glimato, 17, 1697-1724.

Kyle, G.T (1991). Atmospheric Transmission, Emission and scattering, pp

111-112.

Kylling, A (1998). Effect of aerosol on solar UV irradiance during the photo-

chemical activity and solar Ultraviolet Radiation campaign J. Appl. Metorl.

26, 115-119.

Kylling, A., T. person., B. Mayer., T, Svenoe (2000). Determination of an

effective spectral surface abledo from ground – based global and direct UV

irradiance measurements, J. Geophys. Res. 105, 4949-4959.

Lakka, K (2001). Spectral UV measurements at Sodankyla during 1990-2001,

J. Geophys. 74, 1535-1541.

Lenoble, J (1993). Atmospheric Radiative transfer, Deepak publishing,

Hampton, VA, pp. 523

LONDON, J (1985). The observed distribution of atmospheric ozone and it's

variations. NEW YORK.pp. 11-18

Lorento. J., Redano. A., Decabo, X (1996). Influence of urban aerosol on

spectral solar irradiance. Appl. Meteorl, 33, 406-415.

Madronich, S (1987). Photo dissociation in the atmosphere, actinic flux and

the effect of ground reflections and clouds, J. Geophys. Res., 92, 9740-4752.

Madronich, S., R. L McKenzie (1998). Changes of biologically active

ultraviolet radiation reaching the earth surface. J. photochemical 40, 5-19.

Malinovic, S., Kapor, D., (2003). Estimating solar ultraviolet irradiance (290-

400 nm) by means of the NEOPLANTA model: model description and

77

validation. Fifth general conference of the Balkan physical Union ,August 25-

29,2003.Vrnjacka.Serbia and Montenegro.

Manuel, N., Chean, Deliany (1998). A comparison of cloudless sky Erythmal

Ultravaviolet radiation at two sites in southwest Sweden, Int, J.

cilmatolclimatol, 18, 915-930.

Martineg-Lozano, J.A., Casanovas, J., Utrills, M.P (1994). Comparison of

global ultraviolet (295-385 nm) and global radiation on measured during

warm season in Valencia, spain.INT. J. climatological, 14, 93-102.

Mayer, B., G, Seckmeyer, A. kylling (1997). Systematic long term

comparison of spectral UV measurements and UVSPEC modeling results, J.

Geophs. Res, 102, 8755-8767.

Meyer, A., Lipson, G (1998). Enhanced absorption of UV radiation due to

multiple scattering clouds Experimental evidence and theoretical explanation,

J. Geophys Res, 103, 31241- 31254.

Miguel, A.H.,J. Bilbao., P. Salvador (2005), A study of UV total solar

irradiation at rural area of Spain, Solaries, 2nd Joint conference, Athens

(Greece), 2-3, May, 2005.

Miguel, E.C (2005). Ultraviolet Radiation measurement at a rural region in

Spain, J. Geophys. Res. 106, 29832-29839.

Mims, F.M., Frederick, L.E (1994). Cumulus clouds and UV-B Nature. Solar

Energy, 71, 291-296.

Müller, M., A. Kraus., A. Hofzumahaus (1996). Photolysis frequencies

determined from spectroradiometeric measurements of solar actinic UV-

radiation. Geophys. Res. Lett. 22, 679-682.

NASA/TOMS (2000). Total Ozone Mapping Spectrometer home page on

line <http://Jwocky. gsfc nasa. gov>.

Pinedo. J.F. Mireles., Rios (2006). Spectral signature of ultraviolet solar

irrdiance in Zacatecas, J. Appl. Meteorl, 45, 263-269.

78

Seckmeyer, G., Erbb, R., Albold, A (1996). Transmittance of cloud in wave

length-dependent in the UV-range. Geophy. Res. Lett. 23,714-732.

Shetter, R., Müeller, M (1999). Photolysis frequency measurements using

actinic flux spectroradiomerty in the Tropics: instrumentation description and

some results.J.Geophys. Res, 104, 5647-5659.

Shettle, E.E.P., R.W. Fenn (1979). Models for the aerosols of the lower

atmosphere and effects of humidity variations on the optical properties,

Enviro. Res, 79, 214-219.

Taalas, P., G.T. Amantidis., A., Heikkila (2000). Atmospheric UV radiation

on European region, J. Geophys. Res, 105, 4777-4785.

Tadros, M., Metwally. M., Hamed, A (2005). A comparative study on spectral

2, SPCTR- 1881 and SMARTS2 models using direct normal solar irradiance

in different band on ultraviolet Radiation for Cairo and Aswan, Egypt, J.

Atoms and solar terrestrial physics, 67, 1343-1356.

Tena. F (2000). A preliminary estimation of the direct ultraviolet spectral

irradiance in Valencia (Spain): comparison with measured values. J. Nuclear

Technology, 91, 177-180.

Webb, A, R., Weihs, p., Blumathaler, M (1999). Spectral UV irradiance on

sloping surface: a case study. Photo chembiological , 68, 464-470.

Webb, A.,(2000). Ozone depletion and changes in Environmental UV-B

Radiation on, J, Enviro. Sci, 14, 4366-4372.

Webb, A.R (1998). Ultraviolet Instrumentation and applications. Reading,

UK, ISPN Report 104.

Webb, A.R., Stromberg., I.M., Li, H., Bartlett,. M (2000). Airborne spectral

measurements of surface reflectivity at ultraviolet and visible wave lengths, J.

Geophys. Res. 105., 4645-4948.

Webb, A.R.,B. Gardiner (1998). Guide lines for site quality control UV

monitoring Global atmospheric watch, Report No.126, 39 pp., World

Meteorological Origination.

79

Wendish, M., B. Mayer (2003). Vertical distribution of spectral solar

irradiance in cloudless sky, A case study, Geophys. Res. Lett., 30, 1183-1186.

Wenny, B.N., saxena, V.K (2001). Aerosol optical depth measurements and

their impact on surface level of ultraviolet-B radiation, Geophys.Res. 106,

17311-17319.

WHO (1986): A preliminary cloudless standard Atmosphere for radiation

computation. World climate programs WCP-112. WMO/TD-NO 24.world

meteorological organization, Geneva, Switzerland.

WHO (2002): Global solar UV index. A practical Guide. World Heath

Origination, Geneva, Switzerland.

Willmott , C.J (1982). some comments on the evaluation of model

performance . Bull. American Meteorological Society .64:1309-1313.

WMO (1998): Report of the WMO-WHO meeting of exports on

standardization of UV indicey and their dissemination to the public,

Switzerland, 21-24 July 1997. World Meteorological Organization Global

Atmospheric watch NO.127, WMO/TD-NO. 921.

WMO (2002): scientific assessment of ozone depletion: 2002 Global ozone

and Monitoring. Project, Report no, 47, Geneva, Switzerland

Zenfos, c., Nawi, A (2000). A note on the inter annual variations of UV-B

erythmal doses and solar irradiance from ground-based and satellite

observations. INT, J. climatology, 47, 3828-3834.

A‐1

Appendix A SMARTS MODEL, Version 2.9.5

C ****************************************************************************************************** C C CALCULATES CLEAR SKY SPECTRAL SOLAR IRRADIANCES FROM 280 TO 4000 nm. C C Research code written by C. GUEYMARD, Solar Consulting Services c C Version 2.0: November 1995 c Version 2.8: November 1996 c Version 2.9: February 2002 c Version 2.9.1: May 2002 c Version 2.9.2: March 2003 c Version 2.9.3: July 2004 c Version 2.9.4: November 2004 c Version 2.9.5: December 2005 C C C Consult the 'HISTORY.TXT' file and the 'New Features' C Section of the User's Manual for details about the C changes that occurred in the successive versions. C Some input cards may have changed content! C Consult the User's Manual for details and explanations C about the INPUT data cards and OUTPUT files! C C Program SMARTS_295 Double Precision TO3,TAUZ3,DIR,DIF0,DIF,GLOB,GLOBS,DIRH,FHTO,rocb Double Precision DIRS,DIFS,DIREXP,DIFEXP,DGRND,HT,DRAY,TH2O,TH2OP Double Precision TABS,TDIR,DAER,PFGS,PFD,PFB,GAMOZ,WPHT,GRNS Double Precision PPFG,PPFB,PPFD,PPFGS,PhoteV,PFGeV,PFBeV,PFDeV Double Precision PFGSeV,Avogad,evolt,sumd0,fht1,upward,TTP5 Double Precision DIRWL,SUMBN,SUMBX,SUMD,SUMDX,SUMBS,Difccs,Glob0 Double Precision BNORM(2002),GLOBH(2002),GLOBT(2002),DIRX(2002) Double Precision Tcoro3,tz3,AO4,TO4,TO4P,TxO3,TABS0,TABS0p,TAAP Double Precision Julian,dec,Longit,Latit,phi2,xlim,HTa Double Precision TO2,TO2P,TCO2,TCO2P,NLosch,Bw,Bp,Prod,AbO4 Double Precision Tmixd,TmixdP,Trace,TraceP,Phot,Rhor,Rhos,Roro,AO3 Double Precision AmO2,AmCO2,tauo2,tauco2,taa,tas,tat Double Precision AmH2O,wAmw,wAmp,tauw,Bmw,Bmwp,ww02 REAL RB0(4),RB1(4),RB2(4),RB3(4),RDHB(4),limit REAL VL(515),ETSPCT(2002),Output(54),Xout(54),time(2) Real Wvla1(3000),Albdo1(3000),Wvla2(3000),Albdo2(3000) REAL C1(4),C2(4),C3(4),C4(4),C5(4),C6(4),D1(4),D2(4),D3(4),D4(4) REAL BP00(4),BP01(4),D5(4),D6(4) REAL BP02(4),BP10(4),BP11(4),BP12(4),BP20(4),BP21(4),BP22(4) REAL BP30(4),BP31(4),BP32(4),BQ00(4),BQ01(4),BQ02(4) REAL BQ10(4),BQ11(4),BQ12(4),BQ20(4),BQ21(4),BQ22(4) REAL BQ0(7),BQ1(7),BQ2(7),AG41(4),AG42(4),WV(2002) REAL BP0(7),BP1(7),BP2(7),BP3(7),AG0(7),AG1(7),AG2(7),AG3(7)

A‐2

REAL AG4(7),AG00(4),AG01(4),AG02(4),AG10(4),AG11(4),AG12(4) REAL AG20(4),AG21(4),AG22(4),AG30(4),AG31(4),AG32(4),AG40(4) Real Bmx(2),Bmwx(2),intvl,KW REAL DECLI(12),RSUN(12) INTEGER IOUT(54),CIEYr,year,day,DayoYr,DayUT LOGICAL batch CHARACTER*2000 Path CHARACTER*100 FileIn,FileOut,FileExt,FileScn, Usernm CHARACTER*64 AEROS, Spctrm, Comnt Character*48 dummy, smart Character*24 Filen1, Filen2, Lambr1, Lambr2 CHARACTER*24 Load Character*24 Out(54), Seasn2 Character*12 Filter CHARACTER*6 SEASON, Area CHARACTER*4 Atmos, YesNo COMMON /SOLAR1/ WV,WLMN,wlmx,WV1,WV2 COMMON /SOLAR2/ BNORM,GLOBH,GLOBT,DIRX,ETSPCT Common /Solar3/ Dir,Aeros,Tauas,Taurl,Rhox,rpd,pinb,pix4,AmR,WVL, 2 wvln,nx,Znr,Zxr,va,vb,RH Common /Number/ NLosch c DATA O3REF/.34379,.33195,.37707,.34512,.37592,.27761,.3,.28,.33, c 1 .38,.34379/ c DATA UNREF/2.0443E-4,2.1841E-4,1.9867E-4,2.1569E-4,1.8678E-4, c 1 2.1119E-4,2E-4,1E-4,2E-4,1E-4,2.0443E-4/ DATA A0/-0.897/,A1/4.448/,A2/-2.77/,A3/0.312/,RD0/0.408/ DATA RB0/-3.364,3.96,-1.909,0./ DATA RB1/-12.962,34.601,-48.784,27.511/ DATA RB2/9.164,-18.876,23.776,-13.014/ DATA RB3/-.217,-.805,.318,0./ DATA RDHB/-.323,.384,-.17,0./ DATA C1/.4998,.27999,.049331,.57973/ DATA C2/45.236,55.642,7.9767,65.559/ DATA C3/96.233,1382.3,17.726,206.15/ DATA C4/-13.067,-132.47,-14.555,-26.911/ DATA C5/55.506,108.73,41.369,78.478/ DATA C6/83.115,1500.9,-18.384,166.38/ DATA D1/.86887,.69983,.039871,1.1194/ DATA D2/43.547,39.689,12.397,76.251/ DATA D3/-29.719,-26.736,98.641,129.32/ DATA D4/-1.8192,4.0596,-60.939,-17.537/ DATA D5/33.783,31.674,128.0,55.211/ DATA D6/-24.849,-16.936,-34.736,66.192/ DATA BP0/0.,0.,0.,0.,.84372,.64886,.96635/ DATA BP1/0.,0.,0.,0.,.30206,.13465,.073464/ DATA BP2/0.,0.,0.,0.,-.47838,-.30166,-.071847/ DATA BP3/0.,0.,0.,0.,.15647,.083393,.019774/ DATA BQ0/0.,0.,0.,0.,1.2853,2.9784,2.0006/ DATA BQ1/0.,0.,0.,0.,1.486,.61494,7.111/ DATA BQ2/0.,0.,0.,0.,2.8357,3.3122,3.0136/ DATA AG0/0.,0.,0.,0.,.75141,.66851,.77876/ DATA AG1/0.,0.,0.,0.,-.35648,-.20657,-.13625/ DATA AG2/0.,0.,0.,0.,.29982,.1468,.16092/ DATA AG3/0.,0.,0.,0.,-.081346,-.040565,-.056749/ DATA AG4/0.,0.,0.,0.,7.3038E-3,3.8811E-3,6.1178E-3/ DATA BP00/1.0151,.84946,.94016,.99926/ DATA BP01/-6.0574E-3,-9.7903E-3,-3.5957E-4,-5.0201E-3/

A‐3

DATA BP02/5.5945E-5,1.0266E-4,9.8774E-6,4.8169E-5/ DATA BP10/-1.2901E-1,-2.0852E-1,1.2843E-1,-5.5311E-2/ DATA BP11/2.1565E-2,1.2935E-2,1.2117E-3,1.8072E-2/ DATA BP12/-1.95E-4,-9.4275E-5,-2.7557E-5,-1.693E-4/ DATA BP20/2.0622E-1,3.9371E-1,-1.4612E-1,9.0412E-2/ DATA BP21/-3.1109E-2,-2.3536E-2,-8.5631E-4,-2.3949E-2/ DATA BP22/2.8096E-4,1.8413E-4,2.7298E-5,2.2335E-4/ DATA BP30/-8.1528E-2,-1.3342E-1,3.9982E-2,-3.9868E-2/ DATA BP31/1.0582E-2,7.301E-3,3.7258E-4,7.5484E-3/ DATA BP32/-9.5007E-5,-5.7236E-5,-9.5415E-6,-6.9475E-5/ DATA BQ00/-3.0306,7.5308,-3.7748,-4.4981/ DATA BQ01/.12324,-.15526,.13631,.17798/ DATA BQ02/-6.408E-4,1.0762E-3,-7.6824E-4,-9.9386E-4/ DATA BQ10/1.0949,-.88621,1.5129,-5.0756/ DATA BQ11/5.4308E-3,-7.2508E-2,1.5867E-2,.13536/ DATA BQ12/1.7654E-5,9.8766E-4,-1.2999E-4,-6.7061E-4/ DATA BQ20/2.5572,2.2092,2.8725,6.6072/ DATA BQ21/7.2117E-3,2.9849E-2,2.6098E-3,-8.1503E-2/ DATA BQ22/-2.5712E-5,-2.2029E-4,-9.2133E-6,4.5423E-4/ DATA AG00/.75831,.65473,.77681,.77544/ DATA AG01/9.5376E-4,6.0975E-3,-2.7558E-3,-3.1632E-3/ DATA AG02/-2.3126E-6,-4.3907E-5,3.635E-5,3.577E-5/ DATA AG10/6.5007E-2,1.0582E-2,-3.07E-1,-2.3927E-3/ DATA AG11/-1.9238E-2,-2.0473E-2,5.5554E-3,-3.8837E-3/ DATA AG12/1.6785E-4,1.9499E-4,-4.014E-5,2.8519E-5/ DATA AG20/-2.5092E-2,7.2283E-2,1.1744E-1,-9.6464E-3/ DATA AG21/1.5397E-2,1.3209E-2,3.7471E-4,5.8684E-4/ DATA AG22/-1.3813E-4,-1.3393E-4,-1.5242E-6,-4.3942E-6/ DATA AG30/-4.7607E-4,-3.3056E-2,-7.4695E-3,0./ DATA AG31/-4.0963E-3,-3.0744E-3,-1.0596E-3,0./ DATA AG32/3.6814E-5,3.191E-5,6.5979E-6,0./ DATA AG40/7.4163E-4,3.6485E-3,-1.381E-3,0./ DATA AG41/3.5332E-4,2.4708E-4,1.7037E-4,0./ DATA AG42/-3.146E-6,-2.544E-6,-1.0431E-6,0./ DATA RSUN /1.032,1.025,1.011,.994,.978,.969,.967,.975,.99, 1 1.007,1.022,1.031/ DATA DECLI /-20.71,-12.81,-1.8,9.77,18.83,23.07,21.16,13.65, 1 2.89,-8.72,-18.37,-22.99/ C Fundamental physical constants (CODATA, 1998) c c h=6.62606876(52)E-34 J*s (Planck constant) c c=2.99792458E+08 m*s-1 (speed of light) c Avogad= Avogadro number=6.02214199(47)E+23 mol-1 c NLosch=Loschmidt number=Avogad/Vm (m-3) c Vm=22.413996(39)E-03 m3*mol-1 c NLosch converted here to cm-3 c evolt=energy of a photon (J) c PHOT=1/(h*c) [J-1*m-1] c PHOT=5.03411762D+24 evolt=1.602176463D-19 Avogad=6.02214199D+23 NLosch=2.6867775D+19 c c------------------------------- c pinb=3.14159265 pi2=pinb/2. pix4=pinb*4. RPD=pinb/180.

A‐4

c c=================================== c c To obtain the command-line "batch" version, remove the comment sign c "c" on line 188! c batch=.FALSE. c batch=.TRUE. c c=================================== c c RANGE1=1./340.85 epsiln=1e-3 epsilm=1e-6 Iwarn1=0 Iwarn2=0 Iwarn3=0 Iwarn5=0 Iwarn6=0 Iwarn7=0 Iwarn8=0 Iwarn9=0 FileIn ='smarts295.inp.txt' FileOut='smarts295.out.txt' FileExt='smarts295.ext.txt' FileScn='smarts295.scn.txt' C C C Files (some with User-defined filenames) c c---------------------------------------------------------------------- c c c c c********************************************************************** c smart=' Welcome to SMARTS, version 2.9.5!' write(6,314,iostat=Ierr1) smart 314 format(/,35('*'),/,a48,/,35('*')) c if(batch)goto 313 c write(6,3001) 3001 format('$$$ SMARTS_295> ', 1 'Use standard mode with default input file?'/,' [If YES (or Y)', 2 ', execution will start immediately',/,'using the default ', 3 'input file smarts295.inp.txt]',/,' (Y/N) ==>') Read(5,*) YesNo If(YesNo.eq.'Y'.or.YesNo.eq.'y'.or.YesNo.eq.'yes'. 1 or.YesNo.eq.'YES')goto 3003 312 continue Write(6,3140) 3140 Format('$$$ SMARTS_295> What is the path to the input file?',/, 1 ' * Type only "." if in the same folder',/,' * Do NOT type ', 2 'the last "/" of the chain',/,' * 2000 characters max. ==>') Read(5,*) Path Write(6,315) 315 Format('$$$ SMARTS_295> Generic name for all input/output ', 1 'files ',/,' * without any extension',/,' * 100 characters ',

A‐5

2 'max.)? ==>') Read(5,*) Usernm Iname=Index(Usernm,' ') - 1 FileIn =Usernm(1:Iname)//'.inp.txt' FileOut=Usernm(1:Iname)//'.out.txt' FileExt=Usernm(1:Iname)//'.ext.txt' FileScn=Usernm(1:Iname)//'.scn.txt' Write(6,317,iostat=Ierr3) FILEIN,FILEOUT,FILEEXT,filescn 317 Format('$$$ SMARTS_295> You chose the following filenames:',/, 1 ' Input: ',A100,/,' Output: ',A100,/,' Spreadsheet-', 2 'ready: ',A100,/,' Smoothed results: ',A100,/, 3 '$$$ SMARTS_295> Is this OK? (Y/N) ==>') Read(5,*) YesNo If(YesNo.eq.'N'.or.YesNo.eq.'n'.or.YesNo.eq.'no'. 1 or.YesNo.eq.'NO')goto 312 if(Path.eq.'.')goto 3003 mname=Index(Path,' ')-1 FileIn ='/'//FileIn FileOut='/'//FileOut FileExt='/'//FileExt FileScn='/'//FileScn FileIn =Path(1:mname)//FileIn FileOut=Path(1:mname)//FileOut FileExt=Path(1:mname)//FileExt FileScn=Path(1:mname)//FileScn goto 3003 313 continue numarg = iargc() if(numarg.eq.0)goto 3003 if(numarg.eq.1)goto 3002 write(6,322) 322 format('*** ERROR ***',/,' Too many arguments given to SMARTS. ' 1 ,'Only one file name should be given. RUN ABORTED!') STOP 3002 call getarg (1, Usernm) Iname=Index(Usernm,' ') - 1 FileIn =Usernm(1:Iname)//'.inp.txt' FileOut=Usernm(1:Iname)//'.out.txt' FileExt=Usernm(1:Iname)//'.ext.txt' FileScn=Usernm(1:Iname)//'.scn.txt' c c********************************************************************** c c 300 continue TotTime = etime(time) OPEN (UNIT=14,FILE=FileIn,STATUS='OLD') OPEN (UNIT=16,FILE=FileOut,STATUS='NEW') OPEN (UNIT=22,FILE='Gases/Abs_O2.dat',STATUS='OLD') OPEN (UNIT=25,FILE='Gases/Abs_O4.dat',STATUS='OLD') OPEN (UNIT=26,FILE='Gases/Abs_N2.dat',STATUS='OLD') OPEN (UNIT=27,FILE='Gases/Abs_N2O.dat',STATUS='OLD') OPEN (UNIT=28,FILE='Gases/Abs_NO.dat',STATUS='OLD') OPEN (UNIT=29,FILE='Gases/Abs_NO2.dat',STATUS='OLD') OPEN (UNIT=30,FILE='Gases/Abs_NO3.dat',STATUS='OLD') OPEN (UNIT=31,FILE='Gases/Abs_HNO3.dat',STATUS='OLD') OPEN (UNIT=32,FILE='Gases/Abs_SO2U.dat',STATUS='OLD') OPEN (UNIT=33,FILE='Gases/Abs_SO2I.dat',STATUS='OLD') OPEN (UNIT=34,FILE='Gases/Abs_CO.dat',STATUS='OLD') OPEN (UNIT=35,FILE='Gases/Abs_CO2.dat',STATUS='OLD')

A‐6

OPEN (UNIT=36,FILE='Gases/Abs_CH4.dat',STATUS='OLD') OPEN (UNIT=37,FILE='Gases/Abs_NH3.dat',STATUS='OLD') OPEN (UNIT=38,FILE='Gases/Abs_BrO.dat',STATUS='OLD') OPEN (UNIT=39,FILE='Gases/Abs_CH2O.dat',STATUS='OLD') OPEN (UNIT=40,FILE='Gases/Abs_HNO2.dat',STATUS='OLD') OPEN (UNIT=41,FILE='Gases/Abs_ClNO.dat',STATUS='OLD') read(22,*)dummy read(25,*)dummy read(26,*)dummy read(27,*)dummy read(28,*)dummy read(29,*)dummy read(30,*)dummy read(31,*)dummy read(32,*)dummy read(33,*)dummy read(34,*)dummy read(35,*)dummy read(36,*)dummy read(37,*)dummy read(38,*)dummy read(39,*)dummy read(40,*)dummy read(41,*)dummy C CARD 1 C READ(14,*) COMNT C C CARD 2 C READ(14,*) ISPR IF(ISPR.EQ.1)GOTO 301 IF(ISPR.EQ.2)GOTO 302 C C CARD 2a if ISPR=0 C READ(14,*) SPR if(spr.ge.265.)goto 298 if(spr.ge.4e-3)goto 299 spr=4.1e-4 Altit=0. Height=99.9 Zalt=99.9 Iwarn1=1 goto 300 C C APPROXIMATE FUNCTION SPR=F(altit,Latit) ACCORDING TO GUEYMARD C (SOLAR ENERGY 1993)--Improved in 2.9.3 for altit>10 km C 299 continue Zalt=10.+(5.5797-log(spr))/(.14395-.0006335*log(spr)) Altit=0. Height=Zalt goto 300 298 continue pp0=SPR/1013.25 DTA=.014321-.00544*log(pp0) Zalt=Max(0.,(DTA**.5-.11963)/.00272) Altit=Zalt Height=0.

A‐7

if(Zalt.le.4.)goto 300 Altit=0. Height=Zalt GOTO 300 301 CONTINUE C C CARD 2a if ISPR=1 *** "Height" input added in 2.9.3 *** C READ(14,*)SPR,Altit, Height Zalt=Altit+Height if(Zalt.le.100.)goto 300 write(16,1599) 1599 format('*** ERROR #1 ***',/,' The altitude cannot be > 100 km!', 1 /,' RUN ABORTED!') GOTO 998 302 CONTINUE C C CARD 2a if ISPR=2 *** Height added in 2.9.3 *** C READ(14,*)Latit,Altit, Height Zalt=Altit+Height alati=abs(latit) if(Zalt.le.100.)goto 281 write(16,1599) GOTO 998 281 continue If(Latit.lt.-90.D00)Latit=45.D00 if(Zalt.lt.10.)goto 295 SPR=exp((5.5797-.14395*(Zalt-10.))/(1.-.0006335*(Zalt-10.))) goto 300 295 continue PCOR=1. IF(abs(alati-45.).lt.epsiln)GOTO 303 PHI2=Latit*Latit PCOR1=.993+2.0783E-04*alati-1.1589E-06*PHI2 PCOR2=8.855E-03-1.5236E-04*alati-9.2907E-07*PHI2 PCOR=PCOR1+Zalt*PCOR2 303 continue SPR=1013.25*PCOR*EXP(.00177-.11963*Zalt-.00136*Zalt*Zalt) 300 CONTINUE pp0=SPR/1013.25 qp=1.-pp0 c ZAlt2=Zalt*Zalt C C CARD 3 C READ(14,*) iAtmos C C CARD 3a C IF(iAtmos.EQ.0)READ(14,*)TAIR,RH,SEASON,TDAY IF(iAtmos.EQ.1)READ(14,*)Atmos C C*** CARD 4 C READ(14,*) IH2O C 311 continue IF(iAtmos.NE.1)GOTO 320 IF(Atmos.EQ.'USSA')IREF=1

A‐8

IF(Atmos.EQ.'MLS')IREF=2 IF(Atmos.EQ.'MLW')IREF=3 IF(Atmos.EQ.'SAS')IREF=4 IF(Atmos.EQ.'SAW')IREF=5 IF(Atmos.EQ.'TRL')IREF=6 IF(Atmos.EQ.'STS')IREF=7 IF(Atmos.EQ.'STW')IREF=8 IF(Atmos.EQ.'AS')IREF=9 IF(Atmos.EQ.'AW')IREF=10 C C AVERAGE STRATOSPHERIC TEMPERATURE AND REFERENCE ATMOSPHERIC C CONDITIONS C Call RefAtm(Zalt,Pref,TK,TempA,O3ref,RH,Wref,TO3ini,Iref) IF(ISPR.EQ.2)SPR=PREF TAIR=TK-273.15 TKair=TK Tavg=TK TT0=Tk/273.15 Season='SUMMER' if(Iref.eq.3.or.Iref.eq.5.or.Iref.eq.8.or.Iref.eq.10) 1 Season='WINTER' Call Ozon2(Zalt,Ozmin,Ozmax) GOTO 321 320 continue Atmos='USER' IREF=11 wref=1.4164 TKair=TAIR+273.15 TK=TKair Tavg=TDAY+273.15 IF(Height.gt.0.0)TK=Tavg TT0=Tk/273.15 c Estimate ozone temperature at sea level c TO3ini=230.87 if(Season.eq.'WINTER')TO3ini=219.25 c c Converts Temperature at given altitude to ozone temperature c Call Ozon(Zalt,TK,Tempa,Tmin,Tmax,Ozmin,Ozmax) if(tempa.ge.Tmin)goto 397 Iwarn5=1 tempa=Tmin goto 399 397 continue if(tempa.le.Tmax)goto 396 Iwarn6=1 tempa=Tmax 396 continue c 321 continue Seasn2='SPRING/SUMMER' if(Season.eq.'WINTER')Seasn2='FALL/WINTER' w=wref IF(IH2O.ne.1.or.iAtmos.eq.1)goto 349 Iwarn2=1 Call RefAtm(Zalt,dum1,dum2,dum3,dum4,dum5,W,dum6,1)

A‐9

349 continue IF(IH2O.NE.2)GOTO 319 C C SATURATION VAPOR PRESSURE FROM GUEYMARD (J. Appl. Met. 1993) C TK1=TK/100. EVS=EXP(22.329699-49.140396/TK1-10.921853/TK1/TK1-.39015156*TK1) EV=EVS*RH/100. C C W=f(T,RH) USING EMPIRICAL MODEL OF GUEYMARD (SOLAR ENERGY 1994) C ROV=216.7*EV/TK TT=1.+(TAIR/273.15) HV=.4976+1.5265*TT+EXP(13.6897*TT-14.9188*TT**3) W=.1*HV*ROV 319 continue IF(IH2O.NE.0)GOTO 328 C C CARD 4a if IH2O=0 C READ(14,*)W C 328 CONTINUE if(w.le.12.)goto 327 write(16,1027,iostat=Ierr5)w 1027 format('*** ERROR #2 ***',/,' The value selected or calculated ' 1 ,'for precipitable water, w, is ',f10.3,', which is above the ' 2 ,'allowed maximum value of 12 cm. RUN ABORTED!') goto 998 327 continue if(w.le.0.)goto 776 OPEN (UNIT=21,FILE='Gases/Abs_H2O.dat',STATUS='OLD') read(21,*)dummy 776 continue TEMPO=TEMPA TEMPN=TEMPA C C*** CARD 5 C IALT=0 Thick=1. 329 continue READ(14,*)IO3 IF(IO3.ne.1)GOTO 331 IF(iAtmos.ne.0)goto 348 Call RefAtm(Zalt,dum1,dum2,dum3,O3ref,dum5,dum6,dum7,1) Iwarn3=1 348 continue AbO3=O3REF UOC=AbO3 OPEN (UNIT=23,FILE='Gases/Abs_O3UV.dat',STATUS='OLD') OPEN (UNIT=24,FILE='Gases/Abs_O3IR.dat',STATUS='OLD') read(23,*)dummy read(24,*)dummy goto 335 C c c Angstrom's alpha =f(RH) for Shettle & Fenn aerosols (modified in 2.9.2) c

A‐10

XRH=COS(0.9*RH*RPD) xrh2=xrh*xrh xrh3=xrh2*xrh ALPHA1=(C1(IAER)+C2(IAER)*XRH+C3(IAER)*XRH2+c4(IAER)*xrh3)/ 1 (1.+C5(IAER)*XRH+c6(iaer)*xrh2) ALPHA2=(D1(IAER)+D2(IAER)*XRH+D3(IAER)*XRH2+d4(iaer)*xrh3)/ 1 (1.+D5(IAER)*XRH+d6(iaer)*xrh2) if(Iaer.ne.4.or.Height.le.2.0.or.Zalt.lt.6.)goto 3641 alpha1=1.0514 alpha2=1.3623 h2=height*height Deltau=Max(95.-20.*height,10.) Tauavg=(.13712-.007152*height+ 1 .00011794*h2)/(1.+.12521*height+.072153*h2) Taumin=(1.-.01*Deltau)*Tauavg Taumax=(1.+.01*Deltau)*Tauavg if(Zalt.lt.6.)goto 3642 t550mn=exp(-3.2755-.15078*Zalt) t500mn=1.14*t550mn betamn=.441*t550mn Bschmn=.495*t550mn alpha1=1.055 alpha2=1.368 goto 3641 3642 continue if(Season.eq.'SUMMER')goto 3641 alpha1=1.0588 alpha2=1.3736 Tauavg=exp(-3.6752-.13699*height+2.1604/height) Taumin=(1.-.01*deltau)*Tauavg Taumax=(1.+.01*Deltau)*Tauavg 3641 continue RHC=MAX(50.,RH) RHC2=RHC*RHC C C COEFFICIENTS FOR OMEGL (SINGLE SCATTERING ALBEDO) C BP0(IAER)=BP00(IAER)+BP01(IAER)*RHC+BP02(IAER)*RHC2 BP1(IAER)=BP10(IAER)+BP11(IAER)*RHC+BP12(IAER)*RHC2 BP2(IAER)=BP20(IAER)+BP21(IAER)*RHC+BP22(IAER)*RHC2 BP3(IAER)=BP30(IAER)+BP31(IAER)*RHC+BP32(IAER)*RHC2 BQ0(IAER)=BQ00(IAER)+BQ01(IAER)*RHC+BQ02(IAER)*RHC2 BQ1(IAER)=EXP(BQ10(IAER)+BQ11(IAER)*RHC+BQ12(IAER)*RHC2) BQ2(IAER)=BQ20(IAER)+BQ21(IAER)*RHC+BQ22(IAER)*RHC2 C C COEFFICIENTS FOR GG (ASYMMETRY FACTOR) C AG0(IAER)=AG00(IAER)+AG01(IAER)*RHC+AG02(IAER)*RHC2 AG1(IAER)=AG10(IAER)+AG11(IAER)*RHC+AG12(IAER)*RHC2 AG2(IAER)=AG20(IAER)+AG21(IAER)*RHC+AG22(IAER)*RHC2 AG3(IAER)=AG30(IAER)+AG31(IAER)*RHC+AG32(IAER)*RHC2 AG4(IAER)=AG40(IAER)+AG41(IAER)*RHC+AG42(IAER)*RHC2 C C CARD 9 C 355 continue READ(14,*) ITURB C C SELECT THE APPROPRIATE TURBIDITY INPUT C

A‐11

if(iturb.le.5) goto 374 write(16,1949) 1949 format(/,'***** ERROR #3!',/,' Input value for ', 1 ' ITURB on Card 9 is > 5. Please specify a ', 2 'smaller value.'/,' RUN ABORTED!') goto 998 374 continue IF(ITURB.EQ.1) GOTO 351 IF(ITURB.EQ.2) GOTO 352 IF(ITURB.EQ.3) GOTO 353 IF(ITURB.EQ.4) GOTO 354 if(Iturb.eq.5) goto 3560 C C*** CARD 9a if ITURB=0 C READ(14,*)TAU5 if(Zalt.ge.6.)tau5=t500mn GOTO 359 C C*** CARD 9a if ITURB=1 C 351 continue READ(14,*) BETA TAU5=BETA/(0.5**ALPHA2) GOTO 359 352 CONTINUE C C*** CARD 9a if ITURB=2 C READ(14,*)BCHUEP TAU5=BCHUEP*2.302585 goto 359 C C*** CARD 9a if ITURB=5 *** Added in 2.9.3 *** C 3560 continue READ(14,*) Tau550 TAU5=Tau550*(1.1**ALPHA2) 359 CONTINUE if(zalt.ge.6.)goto 357 if(ITURB.ne.5)tau550=Tau5/(1.1**alpha2) if(Aeros.eq.'USER'.or.Iaer.gt.4.or.tau5.lt.1e-4)goto 1825 Call ALFA(Season,Iaer,Iturb,Iref,alpha1,alpha2,tau5,beta, 1 alf1,alf2,t550,0) alpha1=alf1 alpha2=alf2 if(ITURB.ne.5)tau550=t550 goto 1824 1825 continue beta=Tau5*(.5**alpha2) 1824 continue If(Tau550.lt.5.0)goto 1826 Write(16,1920,iostat=Ierr6)Tau550 1920 Format(/,'***** ERROR #4!',/,' Input value for ', 1 ' turbidity is too large (Tau550 = ',f6.1,'). Please specify a ', 2 'smaller value.'/,' RUN ABORTED!') goto 998 1826 continue C C FUNCTION RANGE=F(BETA,ALPHA) FROM NEW FIT - Modified in 2.9.2

A‐12

C RANGE=999. Visi=764.9 If(IAer.ne.1.or.IRef.ne.1)goto 344 If(Iturb.eq.0.or.iturb.eq.2.or.iturb.eq.5)beta=(.5**1.33669)*TAU5 if(iturb.ne.5)Tau550=Tau5/(1.1**.9884) 344 continue If(tau5.lt.0.001)goto 1355 Call VISTAU(Season,Range,Tau550,0) VISI=RANGE/1.306 1355 CONTINUE GOTO 357 354 CONTINUE C C*** CARD 9a if ITURB=4 C READ(14,*)VISI RANGE=1.306*VISI GOTO 356 353 CONTINUE C C CARD 9a if ITURB=3 C READ(14,*)RANGE 356 CONTINUE C C FIT BASED ON MODTRAN4 - Modified in 2.9.2 C if(zalt.ge.6.)goto 357 If(Range.ge.1.0)goto 399 Write(16,192) 192 Format(/,'***** ERROR #5!',/,' Input value for ', 1 ' Meteorological Range is < 1 km. Please specify a larger', 2 ' value.'/,' RUN ABORTED!') goto 998 399 continue Range=Min(Range,999.) VISI=RANGE/1.306 c Call VISTAU(Season,Range,Tau550,1) TAU5=Tau550*(1.1**alpha2) BETA=(0.55**Alpha2)*TAU550 if(Aeros.eq.'USER'.or.Iaer.gt.4)goto 1827 Call ALFA(Season,Iaer,Iturb,Iref,alpha1,alpha2,t5,b, 1 alf1,alf2,tau550,1) alpha1=alf1 alpha2=alf2 tau5=t5 beta=b 1827 continue c 357 CONTINUE IF(ITURB.NE.2)BCHUEP=TAU5/2.302585 ALPHA=(ALPHA1+ALPHA2)/2. if(zalt.lt.6.)goto 3590 iwarn9=1 tau550=t550mn tau5=t500mn beta=betamn Bchuep=bschmn

A‐13

goto 3591 3590 continue if(Tau550.lt.Taumin.or.Tau550.gt.Taumax)Iwarn8=1 3591 continue C WRITE(16,194,iostat=Ierr7) COMNT,Atmos,AEROS 194 FORMAT(/,'****************** SMARTS, version 2.9.5 *********' % ,'**********',//, %' Simple Model of the Atmospheric Radiative Transfer of Sunshine' % ,/,5X,'Chris A. Gueymard, Solar Consulting Services',/,20x, & 'December 2005',//, 1 4X,'This model is documented in FSEC Report PF-270-95',/, 2 ' and in a Solar Energy paper, vol. 71, No.5, 325-346 (2001)', 3 //,' NOTE: These references describe v. 2.8 or earlier!!!',/, 4 ' See the User''s Manual for details on the considerable ',/, 5 ' changes that followed...',//, %'*************************************************************' % ,'***'//,2x,' Reference for this run: ',A64,//,64('-'),//, % '* ATMOSPHERE : ',A4,' AEROSOL TYPE: ',A64,/) WRITE(16,100,iostat=Ierr8) SPR,Altit,Height,RH,W,UOC,uoc*1000., % TAU5,Tau550,BETA,BCHUEP,RANGE,VISI,ALPHA1,ALPHA2,ALPHA,Seasn2 100 FORMAT('* INPUTS:'/,5x,'Pressure (mb) = ',F8.3,' Ground ', % 'Altitude (km) = ',F8.4,/,5x,'Height above ground (km) = ',f8.4, 2 /,5X,'Relative Humidity (%) = ',F6.3,3X, 3 'Precipitable Water (cm) = ',F7.4,/,5x,'Ozone (atm-cm) = ',F6.4, 1 ' or ',f5.1,' Dobson Units',/,3X,'AEROSOLS: ','Optical Depth at' # ,' 500 nm = ',F6.4,' Optical depth at 550 nm = ',f6.4,/, 6 ' Angstrom''s Beta = ',F6.4,' Schuepp''s' %,' B = ',F6.4,/,5x,'Meteorological Range (km) = ',F6.1,' Visi' %,'bility (km) = ',F6.1,/,5x,'Alpha1 = ',F6.4,' Alpha2 = ',F6.4, & ' Mean Angstrom''s Alpha = ',F6.4,/,5x,'Season = ',a24,/) WRITE(16,134,iostat=Ierr9)TKair,Tavg,TEMPA 134 FORMAT('* TEMPERATURES:',/,5x,'Instantaneous at site''s altitude' 1 ,' = ',F5.1,' K',/,5x,'Daily average (reference) at site''s ', 2 'altitude = ',F5.1,' K',/,5x,'Stratospheric Ozone and NO2 ', 3 '(effective) = ',F5.1,' K',/) if(Iwarn5.eq.1)write(16,1018,iostat=Ierr10) Tempa, Tmin 1018 format('** WARNING #1',9('*'),/,'\\ The calculated ozone tempe', 1 'rature, ',f5.1,' K, was below the most probable minimum of ', 2 f5.1,'\\ for this altitude. The latter value has been used ', 4 'for optimum results. Suggestion: double check', 3 ' the daily temperature on input Card 3a',/) if(Iwarn6.eq.1)write(16,1019,iostat=Ierr11) Tempa, Tmax 1019 format('** WARNING #2',9('*'),/,'\\ The calculated ozone tempe', 1 'rature, ',f5.1,' K, was above the most probable maximum of ', 2 f5.1,'\\ for this altitude. The latter value has been used ', 4 'for optimum results. Suggestion: double check', 3 ' the daily temperature on input Card 3a',/) if(IO3.eq.0.and.(UOC.lt.Ozmin.or.UOC.gt.Ozmax))write(16,1021, 1 iostat=Ierr12) UOC, Ozmin, Ozmax 1021 format('** WARNING #3',9('*'),/,'\\ The ozone columnar amount, ', 1 f6.4,' atm-cm, is outside the most probable limits of ',f6.4, 2 ' and ',f6.4,/,'\\ for this altitude. This may produce ', 3 'inconsistent results.',/,'\\ Suggestion: double check the ', 3 'values of IALT and AbO3 on input Card 5a.',/) if(Iwarn1.eq.1)write(16,1301) 1301 format('** WARNING #4',9('*'),/,'\\ Pressure cannot be < 0.000', 1 '41 mb and has been increased to this value.',/,'\\ ',/) if(Iwarn2.eq.1)write(16,1302) 1302 format('** WARNING #5',9('*'),/,'\\ Precipitable water was not '

A‐14

1 ,'provided and no reference atmosphere was specified!',/,'\\ ', 2 'USSA conditions have been used here.',/) if(Iwarn3.eq.1)write(16,1303) 1303 format('** WARNING #6',9('*'),/,'\\ The ozone amount was not pro' 1 ,'vided and no reference atmosphere was specified!',/,'\\ USSA', 2 ' conditions have been used here.',/) if(Iwarn7.eq.1)write(16,1307) 1307 format('** WARNING #7',9('*'),/,'\\ The aerosol type has been ', 1 'changed to "S&F_TROPO" because either the receiver''s height ', 2 'above ground',/,'\\ is > 2 km or its elevation is > 6 km ', 3 'above sea level.',/) if(Iwarn9.eq.1)goto 1311 if(Iwarn8.ne.1.or.height.le.2.0)goto 1311 if(Zalt.lt.15.0.or.Zalt.gt.22.)goto 1310 write(16,1309,iostat=Ierr13)Tau550,Taumin,Taumax 1309 format('** WARNING #8',9('*'),/,'\\ The aerosol optical depth ', 1 'at 550 nm, ',f6.4,' is outside the most probable limits of ', 2 f6.4,' and ',f6.4,/,'\\ for this altitude, assuming a slight ', 3 'background amount of volcanic aerosols. This may produce ', 3 'inconsistent results.',/,'\\ Suggestion: double check the ', 4 'value of your turbidity input on Card 9a.',/) goto 1311 1310 continue write(16,1308,iostat=Ierr14)Tau550,Taumin,Taumax 1308 format('** WARNING #9',9('*'),/,'\\ The aerosol optical depth ', 1 'at 550 nm, ',f6.4,' is outside the most probable limits of ', 2 f6.4,' and ',f6.4,/,'\\ for this altitude. This may produce ', 3 'inconsistent results.',/,'\\ Suggestion: double check the ', 4 'value of your turbidity input on Card 9a.',/) 1311 continue if(Iwarn9.eq.1)write(16,1312) 1312 format('** WARNING #20',9('*'),/,'\\ Receiver is at more than 6 ', 1 'km above sea level, hence the aerosol optical depth has ', 2 'been fixed to a default value, dependent only on altitude.',/) c C*** CARD 10 C Read(14,*) Ialbdx Rhox=0.2 If(Ialbdx.lt.0)goto 383 Call Albdat(Ialbdx,Nwal1,Filen1,Lambr1,Wvla1,Albdo1) Goto 384 C C*** CARD 10a C 383 continue READ(14,*) Rhox 384 Continue C C*** CARD 10b C Read(14,*)Itilt Tilt=0. Rhog=0. Wazim=0. If (Itilt.eq.0)Goto 389 if(height.gt.0.5)write(16,1314) 1314 format('** WARNING #21',9('*'),/,'\\ Receiver is at more than ', 1 '0,5 km above ground, hence the calculation of the reflected ',

A‐15

2 'irradiance from the ground to the tilted plane is not', 3 ' accurate.',/) C C*** CARD 10c C Read(14,*)Ialbdg,TILT,WAZIM c Rhog=Rhox If(Ialbdg.ge.0)Goto 385 C C*** CARD 10d C Read(14,*)Rhog c Goto 389 385 Continue Filen2=Filen1 Lambr2=Lambr1 If(Ialbdg.ne.Ialbdx)Call Albdat(Ialbdg,Nwal2,Filen2, 2 Lambr2,Wvla2,Albdo2) 389 Continue C C*** CARD 11 - Modified in 2.9 C READ(14,*)WLMN,WLMX,Suncor,SolarC If(Ialbdx.ge.0.and.Ialbdx.ne.2) 2 Call Albchk(Nwal1,Filen1,Wvla1,Albdo1,.001*wlmn,.001*wlmx) If(Ialbdg.ge.0.and.Ialbdg.ne.2.and.Ialbdg.ne.Ialbdx.and. 2 Itilt.ne.0) Call Albchk(Nwal2,Filen2,Wvla2,Albdo2, 3 .001*wlmn,.001*wlmx) C C*** CARD 12 C READ(14,*) IPRT IF(IPRT.EQ.0) GOTO 392 C C*** CARD 12a if IPRT=1 TO 3 - Modified in 2.9 C READ(14,*)WPMN,WPMX,INTVL IF(INTVL.LT.0.5)WRITE(16,198) 198 FORMAT(' *** WARNING #18 ***',/,' Parameter INTVL on Card 12a', & ' is too low and will be defaulted to 0.5 nm.') IF(IPRT.lt.2)goto 392 OPEN(UNIT=17,FILE=FileExt,STATUS='NEW') C C*** CARDS 12b if IPRT=2 TO 3 C READ(14,*)IOTOT C C*** CARDS 12c if IPRT=2 TO 3 C READ(14,*)(IOUT(i),i=1,IOTOT) c c======================================= Out(1) ='Extraterrestrial_spectrm' Out(2) ='Direct_normal_irradiance' Out(3) ='Difuse_horizn_irradiance' Out(4) ='Global_horizn_irradiance'

A‐16

Out(5) ='Direct_horizn_irradiance' Out(6) ='Direct_tilted_irradiance' Out(7) ='Difuse_tilted_irradiance' Out(8) ='Global_tilted_irradiance' Out(9) ='Beam_normal_+circumsolar' Out(10)='Difuse_horiz-circumsolar' Out(11)='Circumsolar___irradiance' Out(12)='Global_tilt_photon_irrad' Out(13)='Beam_normal_photon_irrad' Out(14)='Difuse_horiz_photn_irrad' Out(15)='RayleighScat_trnsmittnce' Out(16)='Ozone_totl_transmittance' Out(17)='Trace_gas__transmittance' Out(18)='WaterVapor_transmittance' Out(19)='Mixed_gas__transmittance' Out(20)='Aerosol_tot_transmittnce' Out(21)='Direct_rad_transmittance' Out(22)='RayleighScat_optic_depth' Out(23)='Ozone_totl_optical_depth' Out(24)='Trace_gas__optical_depth' Out(25)='WaterVapor_optical_depth' Out(26)='Mixed_gas__optical_depth' Out(27)='Aeros_spctrl_optic_depth' Out(28)='Single_scattering_albedo' Out(29)='Aerosol_asymmetry_factor' Out(30)='Zonal_ground_reflectance' Out(31)='Local_ground_reflectance' Out(32)='Atmosph_back_reflectance' Out(33)='Global_tilt_reflectd_rad' Out(34)='Upward_reflctd_radiation' Out(35)='Glob_horiz_PAR_phot_flux' Out(36)='Dir_norml_PAR_photn_flux' Out(37)='Dif_horiz_PAR_photn_flux' Out(38)='Glob_tilt_PAR_photn_flux' Out(39)='Spectral_photonic_energy' Out(40)='Globl_horizn_photon_flux' Out(41)='Dirct_normal_photon_flux' Out(42)='Dif_horizntl_photon_flux' Out(43)='Global_tiltd_photon_flux' c Out(46)='DRay' Out(47)='Daer' Out(48)='Dif0' Out(49)='Fda00' Out(50)='Fdazt' Out(51)='Rhoa' c 3. Carbon Monoxide (CO) c if(wvln.lt.2310.0.or.wvln.gt.2405.)goto 881 if(ApCO.le.0.0.and.AbCO.le.0.0)goto 881 Call GSCO(ACO,ApCO,AmPOL,Tcor,TcorP,amdif) TCO=Min(TCO*tcor,1.) TCOP=Min(TCOP*tcorp,1.) 881 continue C C** Misc. Trace gases C c 1. Nitric acid (HNO3) c if(wvln.gt.350.0)goto 882

A‐17

Call GSHNO3(TK,xsHNO3,athno3,ApHNO3,AmPOL,Tcor,TcorP,amdif) THNO3=Min(THNO3*tcor,1.) THNO3P=Min(THNO3P*tcorp,1.) 882 continue C c 2. Nitrogen dioxide (NO2) c if(wvln.gt.926.0)goto 883 Call GSNO2(TK,xsNO2,atno2,ApNO2,AmPOL,Tcor,TcorP,amdif) TNO2=Min(TNO2*tcor,1.) TNO2P=Min(TNO2P*tcorp,1.) 883 continue C c 3. Nitrogen trioxide (NO3) c if(wvln.lt.400.0.or.wvln.gt.703.0)goto 884 if(ApNO3.le.0.0.and.AbNO3.le.0.0)goto 884 Call GSNO3(TK,xsno3,atno3,ApNO3,AmPOL,Tcor,TcorP,amdif) TNO3=Min(TNO3*tcor,1.) TNO3P=Min(TNO3P*tcorp,1.) 884 continue C c 4. Nitric oxide (NO) c if(wvln.lt.2645.0.or.wvln.gt.2745.)goto 885 Call GSNO(ANO,ApNO,AmPOL,Tcor,TcorP,amdif) TNO=Min(TNO*tcor,1.) TNOP=Min(TNOP*tcorp,1.) 885 continue C c 5a. Sulfur Dioxide (SO2) [UV band] c if(wvln.gt.420.0)goto 886 Call GSSO2U(TK,xsSO2,atso2,ApSO2,AmPOL,Tcor,TcorP,amdif) TSO2=Min(TSO2*tcor,1.) TSO2P=Min(TSO2P*tcorp,1.) 886 continue C c 5b. Sulfur Dioxide (SO2) [IR band] c if(wvln.lt.3955.0)goto 887 Call GSSO2I(ASO2,ApSO2,AmPOL,Tcor,TcorP,amdif) TSO2=Min(TSO2*tcor,1.) TSO2P=Min(TSO2P*tcorp,1.) 887 continue C c 6a. Ozone (O3) [UV and VIS bands] c if(ApO3.le.0.0.and.AbO3.le.0.0)goto 889 if(wvln.gt.1091.)goto 888 Call GSO3U(Tref,TK,xso3,a0o3,a1o3,Apo3,AmPOL,tz3,Tcoro3,xo3,AO3) TO3=Min(TxO3*tcoro3,1.D+00) tauz3=Max(tauz3+tz3,0.D00) 888 continue c c 6b. Ozone (O3) [IR band] c if(wvln.lt.2470.)goto 889 TO3=Min(TxO3*exp(-AO3*ApO3*AmPOL),1.D+00) c tauz3=Max(tauz3+ApO3*AO3,0.)

A‐18

889 continue C c 9. Formaldehyde (CH2O) c if(WVLN.gt.400.0)goto 890 if(ApCH2O.le.0.0.and.AbCH2O.le.0.0)goto 890 Call GSCH2O(TK,xsCH2O,atCH2O,ApCH2O,AmPOL,Tcor,TcorP,amdif) TCH2O=Min(TCH2O*tcor,1.) TCH2OP=Min(TCH2OP*tcorp,1.) 890 continue C c 10. Nitrous acid (HNO2) c if(wvln.lt.300.5.or.WVLN.GT.396.5)goto 891 if(ApHNO2.le.0.0.and.AbHNO2.le.0.0)goto 891 Call GSHNO2(TK,xsHNO2,ApHNO2,AmPOL,Tcor,TcorP,amdif) THNO2=Min(THNO2*tcor,1.) THNO2P=Min(THNO2P*tcorp,1.) 891 continue c C c Total gaseous absorption excluding H2O and O3 c c Mixed gases c Tmixd=TO2*TO4*TN2*TN2O*TCO*TCO2*TCH4 TmixdP=TO2P*TO4P*TN2P*TN2OP*TCOP*TCO2P*TCH4P Trace=TNO*TNO2*TNO3*THNO3*TSO2*TNH3*TBrO*TCH2O*THNO2*TClNO TraceP=TNOP*TNO2P*TNO3P*THNO3P*TSO2P 2 *TNH3P*TBrOP*TCH2OP*THNO2P*TClNOP taumix=-log(Tmixd)/AmR tautrc=-log(Trace)/AmR C c----------------------------------------------- c C AEROSOL EXTINCTION C TAUA=0. TAUAS=0. TAA=1.0D00 TAAp=1.0D00 TAS=1.0D00 TAT=1.0D00 IF(IAER.LE.0.OR.IAER.GT.7)GOTO 33 OMEGL=BP0(IAER)+BP1(IAER)*WVL+BP2(IAER)*WVL2+BP3(IAER)*WVL3 IF(wvln.LE.1999.)GOTO 33 BQ=EXP(BQ1(IAER)*(WVL-BQ2(IAER))) OMEGL=1.-(BQ0(IAER)*BQ)/(1.+BQ)**2 GOTO 34 33 CONTINUE C C BRASLAU & DAVE AEROSOL MODEL C1 OR D1 C IF(IAER.NE.8)GOTO 35 OMEGL=.9441-.08817*EXP(1.-3.3815E-3*wvln) IF(wvln.GE.2001.)OMEGL=.8569+.0436E-3*wvln 35 CONTINUE C C BRASLAU & DAVE AEROSOL MODEL C OR D C

A‐19

if(Iaer.ne.9)goto 36 IF(IAER.EQ.9)OMEGL=1.0 goto 34 c c Desert Aerosol (moderate) *** New in 2.9.3 *** c 36 continue if(Iaer.ne.10)goto 39 omegl=.9 if(wvln.gt.500.)omegl=.96 goto 34 c c Desert Aerosol (dust storm) *** New in 2.9.3 *** c 39 continue if(Iaer.ne.11)goto 34 omegl=.6 if(wvln.gt.500.)omegl=.7 c 34 CONTINUE C IF(BETA.GT.0.0)GOTO 37 OMEGL=1.0 GOTO 38 37 continue TAUA=BETA/WVL**ALPHA2 IF(wvln.LE.499.) TAUA=BETAC/(WVL**ALPHA1) IF(wvln.GE.1001.0.AND.IAER.EQ.8)TAUA=BETA/WVL**.825 if(iaer.ne.1.or.iref.ne.1)goto 777 alpha=1.1696-4.6814*wvl+12.96*wvl2 if(abs(wvl-0.3).lt.1e-4)alpha=.93178 if(wvl.gt.0.3.and.wvl.lt.0.337)alpha=1.443-4.6051*wvl+9.6723*wvl2 if(abs(wvl-0.337).lt.1e-4)alpha=.989 if(wvl.gt.0.337.and.wvl.lt.0.55)alpha=.98264+.032539*wvl 1 -.040251*wvl2 if(abs(wvl-0.55).lt.1e-4)alpha=.98839 if(wvl.gt.0.55.and.wvl.lt.0.694)alpha=-32.0108+151.02*wvl-229.75 1 *wvl2+116.83*wvl3 if(abs(wvl-0.694).lt.1e-4)alpha=1.192 if(wvl.gt.0.694.and.wvl.lt.1.06)alpha=-1.9669+9.576*wvl-9.4345 1 *wvl2+3.1621*wvl3 if(abs(wvl-1.06).lt.1e-4)alpha=1.3485 if(wvl.gt.1.06.and.wvl.le.1.536)alpha=-.25628+3.0677*wvl-1.9011 1 *wvl2+.41005*wvl3 if(wvl.gt.1.536.and.wvl.le.2.0)alpha=-1.3018+3.7405*wvl-1.6633 1 *wvl2+.25856*wvl3 if(wvl.gt.2.0.and.wvl.le.2.25)alpha=2.1665-.40189*wvl+.057873 1 *wvl2 if(wvl.gt.2.25.and.wvl.le.2.5)alpha=2.1188-.35073*wvl+.044553*wvl2 if(wvl.gt.2.5.and.wvl.le.2.7)alpha=4.3108-1.5493*wvl+.17324*wvl2 if(wvl.gt.2.7.and.wvl.le.3.0)alpha=2.1947-.33892*wvl+.015213*wvl2 if(wvl.gt.3.0.and.wvl.le.3.39)alpha=-2.993+3.3795*wvl-.86713*wvl2 1 +.073101*wvl3 if(wvl.gt.3.39.and.wvl.le.3.75)alpha=1.6801-.12171*wvl+.0068994 1 *wvl2 if(wvl.gt.3.75)alpha=2.0473-.27977*wvl+.022939*wvl2 Taua=Tau5/(2.*wvl)**alpha 777 continue TAUAS=OMEGL*TAUA Tauaa=Taua-Tauas

A‐20

TAS=EXP(-TAUAS*AmAER) TAT=EXP(-TAUA*AmAER) TAA=EXP(-TAUAA*AmAER) 38 CONTINUE C c----------------------------------------------- c C BEAM RADIATION C TSCAT=TR*TAS TABS0=TH2O*Tmixd*Trace*TAA TAAp=EXP(-TAUAA*Amdif) TABS0P=TH2OP*TmixdP*TraceP*TAAP TABS=TABS0*TO3 TDIR=TABS*TSCAT DIR=H0*TDIR DIRH=DIR*ZCOS H0H=H0*ZCOS FHTO=1. FHT1=1. IF(TAUZ3.gt.5d-6)FHTO=EXP(-FHTcz-FHTdx*(TAUZ3-2.D00)) c c corrected in 2.9.2 c IF(tauz3.LE.2.D00)FHTO=EXP(-FHTcx*TAUZ3-FHTcy*(TAUZ3**.95)) c c Improved multiple scattering algorithm--New in 2.9.3, revised in 2.9.5 c Fda00=1. Fdazt=1. Fdif=1. if(t5.le.0.03)goto 3909 ssaro=Taurl/(Taurl+Tauz3) Taurf=(ssaro**.5)*Taurl*Taurl Fda00=(trb0+trb1*Taurf)/(1.+trb2*(Taurf**.5)) if(wvln.gt.294.)Fdazt=tzb0+tzb1*Taurf+tzb2*Taurf**.5 3909 continue if(wvln.gt.400.)goto 3900 Fda00=1. if(wvln.le.294.0.or.t5.le.0.03)goto 3908 Fda00=(tra0+tra1*Taurf)/(1.+tra2*Taurf) 3908 continue FHT1=.962-9.1*tauz3 if(Tauz3.le.0.01D00)goto 3900 if(Tauz3.le.22.5D00)goto 3907 FHT1=Min(12.D00,FHTa0+Tauz3*FHTa1) if(Amo3.le.2.0)goto 3900 FHT1=Min(12.D00,FHTb0+Tauz3*FHTb1) goto 3900 3907 continue if(Tauz3.le.15.5D00)goto 3906 FHT1=Min(7.D00,FHTc0+Tauz3*FHTc1) if(Amo3.le.1.6)goto 3900 FHT1=Min(6.D00,FHTd0+Tauz3*FHTd1) goto 3900 3906 continue if(Tauz3.le.10.D00)goto 3905 FHT1=Min(9.D00,FHTe0+Tauz3*FHTe1)

A‐21

if(Amo3.le.1.9)goto 3900 FHT1=Min(8.D00,FHTf0+Tauz3*FHTf1) goto 3900 3905 continue if(Tauz3.le.6.0D00)goto 3904 ra0=ra00 if(Amo3.gt.2.2)ra0=ra01 if(Amo3.le.2.6)goto 3910 ra1=ra10 goto 3912 3910 continue if(Amo3.le.1.72)goto 3914 ra1=ra11 goto 3912 3914 continue ra1=ra12 3912 continue FHT1=Min(10.D00,ra0+(Tauz3-6.D00)*ra1) goto 3900 3904 continue c if(Tauz3.le.1.0D00)goto 3902 if(Amo3.gt.3.2)goto 3915 ra0=ra02 ra1=ra13 FHT1=Min(2.D00,ra0+Tauz3*ra1) FHT1x=Min(2.,ra0+2.505*ra1) goto 3903 3915 continue ra0=ra03 ra1=ra14 FHT1=Min(2.D00,ra0+Tauz3*ra1) FHT1x=Min(2.,ra0+2.505*ra1) 3903 continue if(Tauz3.le.2.505D00)goto 3900 ra0=FHT1x if(Amo3.gt.3.5)ra0=ra04 ra1=ra15 if(Amo3.gt.2.4)ra1=ra16 FHT1=Min(7.5D00,ra0+(Tauz3-2.505D00)*ra1) goto 3900 3902 continue if(Tauz3.le.0.1D00)goto 3901 xlim=1.D00 if(Amo3.gt.2.)xlim=1.6D00 FHT1=Min(xlim,ra05+Tauz3*ra17) goto 3900 3901 continue FHT1=Min(1.D00,ra06+Tauz3*ra18) 3900 continue FHT1=Max(FHT1,.002) if(Tauz3.lt.5.0D00)FHT1=Max(FHT1,.5) FHTO=FHTO/FHT1 HT=H0H IF(Zenit.ge.89.)HT=H0/AmR HTa=HT*TABS0p*FHTO C c-------------------------------------------------- c C Diffuse radiation (improved in 2.9.5)

A‐22

C c-------------------------------------------------- c C Asymmetry and forward scatterance C if(IAER.ne.10)goto 40 GG=.71 if(wvln.gt.500.)gg=.675 40 continue if(IAER.ne.11)goto 44 GG=.89 if(wvln.gt.500.)gg=.85 44 continue IF(IAER.NE.8.AND.IAER.NE.9)GOTO 42 GG=0.8042 GOTO 43 42 CONTINUE IF(IAER.LE.0.OR.IAER.GT.7)GOTO 43 GG=AG0(IAER)+AG1(IAER)*WVL+AG2(IAER)*WVL2+AG3(IAER) % *WVL3+AG4(IAER)*WVL4 43 CONTINUE GG=MIN(0.99,GG) ALG=log(1.-GG) AFS=ALG*(1.459+ALG*(.1595+ALG*.4129)) BFS=ALG*(.0783+ALG*(-.3824-ALG*.5874)) FA1=1.-.5*EXP((AFS+BFS*ZCOS)*ZCOS) FA1P=1.-.5*EXP((AFS+BFS*.6)*.6) C C** 1. DIFFUSE RADIATION FROM RAYLEIGH SCATTERING C DRAY=0.D00 FR=0.5 FRP=0.5 IF(TAURL.GE.EPSIR)FR=.5*EXP(-((TAURL-EPSIR)/SIGMAR)**EXPR) IF(TAURL.GE.EPSIRP)FRP=.5*EXP(-.1957*(TAURL-0.0648)**1.32) 41 CONTINUE DRAY=HTa*FR*(1.-TR)*(Max(Tas,1e-10)**.167) c C C 2. DIFFUSE RADIATION FROM AEROSOL SCATTERING C DAER=0.D00 IF(BETA.gt.0.0)DAER=HTa*FA1*(TR**.167)*(1.-TAS)*Fda00*Fdazt C C Sky diffuse before backscattering C Fdifz=1. Fdiftz=1. if(wvln.gt.294.)goto 7200 Fdifz=fdifa0+fdifa1*wvl if(zenit.ge.45.)Fdiftz=fdifb0+fdifb1*Ama1+fdifb2*Ama2 7200 continue DIF0=Fdifz*Fdiftz*(DRAY+DAER) Glob0=Dirh+Dif0 C C 3. BACKSCATTERING - reflection from ground to space and back C TRP=EXP(-Amdif*TAURL) TAUAP=TAUA*Amdif TASP=EXP(-OMEGL*TAUAP)

A‐23

TTp5=Tabs0p**.5 GAMOZ=1. IF(wvln.LE.379.5)GAMOZ=EXP(-1D+5*(4.8344+23.088*(AbO3+ApO3)) 1 *(.38-WVL)**5.8) Rhob0=Rhox Rhob=Rhox Rhod=Rhox Rhor=0.D00 Rhoa=0. Rhos=0.D00 Roro=0. Dgrnd=0.D00 If(Ialbdx.lt.0)goto 411 rocb=0. if(Glob0.gt.0.D00)rocb=Dirh/Glob0 Call Albdos(Ialbdx,Nwal1,Albdo1,Wvla1,Wvl,Zenit,Zcos,Rhob0,Rhob, 1 Rhod) 411 continue Rho=Max(Rhob,Rhod) If(TTP5.le.1D-12) goto 413 RHOR=TTP5*((1.-FRP)**.85)*(TASP**.05)*(1.-TRP)*GAMOZ c c New in 2.9.4/revised in 2.9.5 c Fatau=0. if(tau550.lt.0.03)goto 3999 if(wvl.gt.0.35)goto 3992 Fatau=exp(alba00+alba01*wvl) if(t5.le.0.2)goto 3998 Fatau=exp(alba0+alba1*wvl+alba2*wvl2) goto 3998 3992 continue if(wvl.gt.0.5)goto 3994 Fatau=exp(albb0+albb1*wvl+albb2*wvl2) goto 3998 3994 continue Fatau=(albc0+albc1*wvl+albc2*wvl2+albc3*wvl3)/(1.+albc4*wvl) 3998 continue c RHOA=TTP5*((1.-FA1P)**.85)*GAMOZ*Fatau 3999 continue RHOS=RHOR+RHOA If(Ialbdx.ge.0)Rho=Rhob*rocb+Rhod*(1.-rocb) RORO=RHO*RHOS Upward=Rho*Glob0 DGRND=Upward*RHOS/(1.-RORO) 413 continue c DIF=DIF0+DGRND GLOB=DIRH+DIF C c----------------------------------------------- c c UV calculations c IF(IUV.EQ.1.AND.wvln.LE.400.)CALL UVDAT(ER0,ER1,ER2,

A‐24

# ER3,ER4,DNA,PHO,ECAL,ACG,POL,SIS,PRT,SCUPH,SCUPM,wvln) GERY0=GLOB*ER0 GERY1=GLOB*ER1 GERY2=GLOB*ER2 GERY3=GLOB*ER3 GERY4=GLOB*ER4 GDNA=GLOB*DNA GECAL=GLOB*ECAL GPHO=GLOB*PHO GACG=GLOB*ACG GPOL=GLOB*POL GSIS=GLOB*SIS GPRT=GLOB*PRT GSCUPH=GLOB*SCUPH GSCUPM=GLOB*SCUPM C c----------------------------------------------- c C** CIRCUMSOLAR CORRECTION FOR A SIMULATED RADIOMETER C direxp=dir difexp=dif difcc=0. IF(ICIRC.le.0)GOTO 77 call Circum (Difccs,Iaer,Icirc) c c Correction for the diminished aureole close to the horizon c cexp=1. if(Zenit.le.(90.-apert))goto 76 zexp=2.*acos((pi2-zr)/(apert*rpd)) cexp=1.-.5*(zexp-sin(zexp))/pinb 76 continue difexp=Max(0.1D00*dif,dif-cexp*difccs*zcos) difcc=(Dif-Difexp)/(cexp*zcos) direxp=dir+difcc 77 CONTINUE c c Calculate current Julian Day c liAux1 =(Month-14)/12 LiAux2=(1461*(Year + 4800 + liAux1))/4 1 + (367*(Month- 2-12*liAux1))/12 2 - (3*((Year + 4900+ liAux1)/100))/4+Day-32075 Julian=Float(LiAux2)-0.5+dHour/24. c c Calculate difference in days between the current Julian Day c and JD 2451545.0, which is noon 1 January 2000 Universal Time c Elapsd = Julian-2451545.0 c c Calculate ecliptic coordinates (ecliptic longitude and obliquity of c the ecliptic in radians) but without limiting the angle to be less c than 2*Pi (i.e., the result may be greater than 2*Pi) c Omega=2.1429-0.0010394594*Elapsd SunLng = 4.8950630+ 0.017202791698*Elapsd Anomly = 6.2400600+ 0.0172019699*Elapsd EclipL = SunLng + 0.03341607*sin(Anomly) + 0.00034894* 1 sin(2.*Anomly)-0.0001134-0.0000203*sin(Omega)

A‐25

EclipO = 0.4090928 - 6.2140e-9*Elapsd+0.0000396*cos(Omega) c c Calculate celestial coordinates (right ascension and declination) c in radians but without limiting the angle to be less than 2*Pi c (i.e., the result may be greater than 2*Pi) c SinELg= sin(EclipL) dY = cos(EclipO) * SinELg dX = cos(EclipL) RightA = atan2(dY,dX) if(RightA.lt.0.0) RightA = RightA + twopi Decli = asin(sin(EclipO)*SinELg) c c Calculate local coordinates (azimuth and zenith angle) in degrees c GMST = 6.6974243242 + 0.0657098283*Elapsd + dHour LMST = (GMST*15. + dLong)*rad HrAngl = LMST - RightA dRLat = dLat*rad cosLat = cos(dRLat) sinLat = sin(dRLat) cosHA= cos(HrAngl) Zenith = acos(cosLat*cosHA*cos(Decli) + sin(Decli)*sinLat) dY = -sin(HrAngl) dX = tan(Decli)*cosLat - sinLat*cosHA Azimu = atan2(dY, dX) if (Azimu.lt. 0.0)Azimu = Azimu + twopi Azimu = Azimu/rad c c Parallax Correction c Paralx=(Radius/AUnit)*sin(Zenith) Zenith=(Zenith + Paralx)/rad c c Sun-Earth actual distance in AU (from Michalsky's paper) c R=1.00014-.01671*cos(Anomly)-.00014*cos(2.*Anomly) c c Equation of Time (in min, from Michalsky's paper) c RightA=RightA/rad SunLng=SunLng/rad xsun=-aint(abs(SunLng)/360.) if(Sunlng.lt.0.)xsun=-xsun+1. SunLng=SunLng+xsun*360. EOT=(SunLng-RightA)*4. C C REFRACTION CORRECTION FOR ACTUAL ATMOSPHERIC CONDITIONS (P,T) C ELD=90.-Zenith ELD2=ELD*ELD REFR=0. PT=P/T IF(ELD.LT.15.0.AND.ELD.GE.-2.5)REFR=PT*(.1594+.0196*ELD+ # 2E-5*ELD2)/(1.+.505*ELD+.0845*ELD2) IF(ELD.GE.15.0.AND.ELD.LT.90.)REFR=.00452*PT/TAN(ELD*rad) Zenith=90.-(ELD+REFR) zenit=real(zenith) azim=real(azimu) c

A‐26

c Declination in degrees c Decli=Decli/rad return end C C c SUBROUTINE UVDAT(ERY0,ERY1,ERY2,ERY3,ERY4,DNA,PHO,ECAL,ACG, % POL,SIS,PRT,SCUPH,SCUPM,wvln) C C Calculates different erythema and DNA action/damage curves C REAL A(6),B(6) DATA B/-1.3448,1.2203E4,5.2729E5,-1.33E7,7.4736E7,54.81/ DATA A/41.791,1.3853E4,3.6663E5,-1.1993E7,7.5816E7,53.426/ C DW=wvln-300. DW2=DW*DW DW3=DW*DW2 DW4=DW*DW3 DW5=DW*DW4 DW6=DW*DW5 DW7=DW*DW6 DW8=DW*DW7 DW325=wvln-325. wvl=wvln/1000. XL=-log(wvl) XL2=XL*XL XL3=XL*XL2 XL4=XL2*XL2 C C ERYTHEMA SPECTRUM OF CIE 1987 (MCKINLAY & DIFFEY) C ERY0=1.0 IF(wvln.GE.299.0.AND.wvln.Lt.329.)ERY0=10.**(.094*(298.-wvln)) IF(wvln.GE.329.)ERY0=10.**(.015*(139.-wvln)) C C ERYTHEMA SPECTRUM OF KOMHYR AND MACHTA, fitted by GREEN ET AL. C (1974) C EXPL=EXP((DW+3.5)/2.692) ERY1=.04485/(1.+EXP((DW-11.4)/3.13))+3.9796*EXPL/(1.+EXPL)**2 C C ERYTHEMA SPECTRUM OF COBLENTZ AND STAIR (1934), fitted by C GREEN ET AL. (1975) C EXPL2=EXP((DW+3.)/3.21) ERY2=0. IF(wvln.LE.325.)ERY2=4.*EXPL2/(1.+EXPL2)**2 C C ERYTHEMA SPECTRUM OF PARRISH ET AL. (1982), AS FITTED BY C BJORN (1989) C ERY3=EXP(-.4232-.1413*DW-.0105*DW2+2E-4*DW3+8.982E-6*DW4- # 3.921E-7*DW5+5.623E-9*DW6-3.603E-11*DW7+8.759E-14*DW8) C C ERYTHEMA SPECTRUM OF DIFFEY (1982) MODIFIED BY BJORN (1989) C ERY4=0.

A‐27

IF(wvln.GE.326.0.OR.wvln.LE.284.)GOTO 90 ERY4=.98-.0957*DW IF(wvln.gt.310.)ERY4=EXP(-5.0188-.118*DW325+9.382E-4*DW325*DW325) 90 CONTINUE C C PLANT/DNA SPECTRUM OF SETLOW (1974) AS FITTED BY C GREEN & MO (1975) C DNA=0. IF(wvln.GE.366.)GOTO 99 DNA=EXP(13.82*(-1.+1./(1.+EXP((wvln-310.)/9.)))) 99 CONTINUE C C PHOTOSYNTHESIS INHIBITION SPECTRUM OF CALDWELL ET AL. (1986) C PHO=0. IF(wvln.LE.340.)PHO=13.42*EXP(106.219-.6122*wvln 1 +.0008316*wvln*wvln) C C CALDWELL (1971) BIOLOGICAL ACTION CURVE, AS FITTED BY C GREEN ET AL. (1974) C ECAL=0. IF(wvln.LE.313.)ECAL=2.618*(1.-(wvln/313.3)**2)*EXP(-DW/31.08) C C ACGIH (1978) SAFETY SPECTRUM, AS FITTED BY WESTER (1981, 1984) C ACG=0. IF(wvln.Lt.300.)ACG=1.-0.36*((wvln-270.)/20.)**1.64 IF(wvln.GE.300.0.AND.wvln.LE.315.)ACG=0.3*0.74**DW C C POLYCHROMATIC ACTION FOR HIGHER PLANTS,data fom Caldwell et al. C (1986); fit by Gueymard C POL=EXP(40.355-106.88*XL+59.307*XL2) C C SYSTEMATIC IMMUNOSUPPRESSION, data from deFabo et al. (1990); C fit by Gueymard C SIS=EXP(-42.826+45.056*XL-9.3345*XL2) C C DNA TO PROTEIN CROSSLINKS, data from Peak & Peak (1986); C fit by Gueymard C PRT=EXP(-1305.8+5287.4*XL-7917.5*XL2+5154.1*XL3-1228.3*XL4) C C SKIN CARCINOGENESIS FOR MICE AND HUMANS, data from C de Gruijl & Van der Leun (1994); fit by Gueymard C H=WVL-.299 X=WVL-.293 SH=0. SX=0. H1=1. X1=1. DO 10 I=1,5 H1=H1*H X1=X1*X SH=SH+A(I)*H1 SX=SX+B(I)*X1

A‐28

10 CONTINUE SCUPH=EXP(-SH/(1.+A(6)*H)) SCUPM=EXP(-SX/(1.+B(6)*X)) C 999 continue RETURN END c Subroutine VISTAU(Season,Range,Tau,index) c Real vs1(5),vw1(5),vs2(3),vw2(3),vs3(2),vw3(2) Character*6 Season Data vs1 /-3.2998,-5.37,156.14,42.389,48.957/ Data vs2 /.026483,7.133,-6.6238/ Data vs3 /.039987,.43928/ Data vw1 /-3.6629,-6.5109,165.85,44.857,51.968/ Data vw2 /.010149,6.7705,-1.7703/ Data vw3 /.023339,.27928/ c if(index.eq.1)goto 1 tln=log(Tau) Range=999. c c*** (Index=0) Calculate Range from Tau c if(season.eq.'WINTER')goto 345 c c Calculations for SPRING/SUMMER conditions c if(Tau.lt.0.0402)goto 346 if(Tau.le.0.0416)goto 3442 if(Tau.lt.0.0901)goto 3440 delta1=(vs1(4)*tln-vs1(2))*(vs1(4)*tln-vs1(2))- 1 4.*(vs1(5)*tln-vs1(3))*(tln-vs1(1)) Range=1./(.001+.5*(vs1(2)-vs1(4)*tln-(delta1**.5))/ 1 (vs1(5)*tln-vs1(3))) goto 346 3440 continue delta2=vs2(2)*vs2(2)+4.*vs2(3)*(Tau-vs2(1)) Range=Min(999.,1./(.001+.5*(vs2(2)-(delta2**.5))/(-vs2(3)))) goto 346 3442 continue Range=1./(.001+(Tau-vs3(1))/vs3(2)) 346 continue Range=Min(Range,999.) goto 30 345 continue c c Calculations for FALL/WINTER conditions c if(Tau.lt.0.0235)goto 346 if(Tau.le.0.0245)goto 3446 if(Tau.lt.0.0709)goto 3444 delta1=(vw1(4)*tln-vw1(2))*(vw1(4)*tln-vw1(2))- 1 4.*(vw1(5)*tln-vw1(3))*(tln-vw1(1)) Range=1./(.001+.5*(vw1(2)-vw1(4)*tln-(delta1**.5))/ 1 (vw1(5)*tln-vw1(3))) goto 346 3444 continue delta2=vw2(2)*vw2(2)+4.*vw2(3)*(Tau-vw2(1)) Range=Min(999.,1./(.001+.5*(vw2(2)-(delta2**.5))/(-vw2(3))))

A‐29

goto 346 3446 continue Range=1./(.001+(Tau-vw3(1))/vw3(2)) goto 346 c 1 continue c c*** (Index=1) Calculate Tau from Range c YVIS=(1./RANGE)-.001 Yvis2=Yvis*Yvis if(Range.lt.100.)goto 3447 if(Range.gt.320.)goto 3448 Tau=vs2(1)+vs2(2)*Yvis+vs2(3)*Yvis2 if(Season.eq.'WINTER')Tau=vw2(1)+vw2(2)*Yvis+vw2(3)*Yvis2 goto 30 3447 continue Tau=exp((vs1(1)+vs1(2)*Yvis+vs1(3)*Yvis2)/ 1 (1.+vs1(4)*Yvis+vs1(5)*Yvis2)) if(Season.eq.'WINTER')Tau=exp((vw1(1)+vw1(2)*Yvis+ 1 vw1(3)*Yvis2)/(1.+vw1(4)*Yvis+vw1(5)*Yvis2)) goto 30 3448 continue Tau=vs3(1)+vs3(2)*Yvis if(Season.eq.'WINTER')Tau=vw3(1)+vw3(2)*Yvis 30 continue c Return End

ى

ميلي

ة على ة

الجامعة

علوم الجو

ي

ميل الجم 1428

جويةفسجية

-ة العلوم

في عسفة

صالحي19(

(

س جمقيرمضان

مل الج البنفس

آلية- جو رية

توراه فلس قبل

حمن الص994( زياء

)2002( و

د ق.م.أ

ي

لعواملفوق

علوم الجلمستنصردرجة دآتقدمة من

عبدالرحس علوم فيز

ر علوم جو

أشراف

حث العلمي

الع ضعة الف

الى قسمالبات نيل دمق

محمد عكالوريوس

ماجستير

زآي20

اقلعالي والبح

نصرية

و

بعضاألشع

حة مقدمة

من متطلب

علي مبك

ق أحمد ز07ألول

ورية العررة العليم العمعة المستنص

العلومعلوم الجو

تأثيرا

أطروح

آجزء م

ع

د ناطق.متشرين األ

جمهووزارالجامآلية

قسم ع

ت

م.أ

ph.d thesis

Documents

member signature

assistant professor

supervisor signature

chairman signature

expert date

alnaimi title

kais jamil aljumaily

college of science date