1992 CEDAR WorkshopBoulder, CO

June 21-26, 1992

Tutorial Lecture

by Raymond RobleNational Center for Atmospheric

Research

Overview of theThermosphere/lonosphere General

Circulation Model (TIGCM)

I

NCARTHERMOSPHERE/ieNBSFHEKE

GENERAL CIRCULATION MODEL(TICCM)

Primitive equations of dynamic meteorology adaptedto thermospheric heights

• Horizontal grid 5° latitude x 5° longitude, geographic

• Vertical grid —25 constant pressure surfaces, 2 gridpoints per scale height, 95 to 500 km

• Time step 240 or 300 S

INPUT

• Solar EUV and UV radiation 5 to 250 nm

• Empirical ionospheric convection and auroral particleprecipitation models

LONG RANGE MODEL DEVELOPMENT

1980

1989

MaZS1991

IonosphereDynamoMSIS

Aurora

Solar

Tides

DynamoAurora

Solar

Tides

Aurora

Solar

Tides

199^ Aurora (GEM^ Solar(R]>E)

199C Aurora (GEMJSolar (RISE)

TGCM

(100-500KM)

TIOCM

(•95-5(K)KM

TIE-GCM

('Qo-S'OO)

Atmobphcre Exi)l()r(TDynamics ExplorerRadar and Airglow

Atmosphere C\i»lorerDynamics Exph)r«TAir Force

CEDAJl

Atmosphere Exi)lor('rDynamic> Exi)l(>r< rSan Marco^

CED.\R

GEM

TIME-GCM

(30-oO()KM) ISTP

CEDAH

GEM

Air I orcc

CCM/TIME-GCM(0-500IvM)

U\RS

EOS

Global ChangeTimed

THERMODYNAMIC EQUATION p_ (3Pv "C

dT _ ge' ±_ .at PqC, dz

Kj. dT ^ PPr

+1 arlH dz

Molecular thermalconduction

- V •VT - WdT RTdz Cp m

horizontaladvection

vertical advectionand adiabaticexpansion

Iipppr Rnnndarv Conditions

No heat source or heat

sink at upper boundary

dT

dz= 0

Eddy thermalconduction

+(Q-L)

heat sources andradiative losses

TiOwer Boundary ConditionsTemperature specified r = r, (2 = - 7)

1

THE EASTWARD MOMENTUM EQUATION

du _ gg ^ ddt "" Pq dz

fL duH dz

+ / + — tan (^ - XxyV

-X u - V•Vu - w4^ T —I- (^X + Ky ^A„ u V VU

THE NORTHWARD MOMENTUM EQUATIONy \

du ^ je' d ^ _ / 4- Ji tan - X„ u-^-T7 l/_ 1

-x,y" -V-V.; li - 7

THE CONTINUITY EQUATION

1 +e^ 4-(«-'«')rcos 4> d<t> + rcos ^ dX 5z

THE HYDROSTATIC EQUATION

a<j> RT

Jpper Boundary Conditions

No sources of momemtuni

at upper boundary

imKCT Boiinflarv Conditions

Specified U — U,(zV = v,(z

(z

dz m

du _ ^ _ 0dz dz dz

a

= 0

T 400 km

MagneticField Line

ThermosphericWind

I

IONOSPHERE

J- 2(X)km

400 km

J- 200 km

Ions and electronsspiral up

IONOSPHERE

Ions and electronsdown

High atmospheric densityresults in increased electron-ion chemical recombination

LoMtf atmospheric densityresults in decreosedelectron-ion chemicalrecombination

ThermosphericWind

ION DRAG PARAMETERS

= Xj (1 - sin^ S cos- I)

Xyy = Xi (1 - cos^ Scos^ /)

Xjpy = + Xj sin Scos Scos^ / + Xg sin I

Xyj = + X^ sin Scos 6 cos- / + Xg sin I

where 6 is the magnetic declination angle, 1 is the magnetic dip angle and

(TpB' ChB-\ = — Xo = —

where Gp and (Tjj are the Pedersen and Hall electrical conductivity, respectively. B is thestrength of the magnetic field = 0.282 y 1 + 3 • COS" <j>^ Gauss, <j>i^ is the magnetic colati-tude, and p is the TGCM density.

JOULE HEATING

The Joule heating for displaced poles is

Qj = f + x„ (y,-y„ f + - x -u„)(v,-y„)

where and V,- are the geographic zonal and meridional ion drift velocities defined by theHeelis c< al (1982) empirical model and and are the zonal and meridional neutralwind components determined at a given time step in the TGCM.

^mPi^iCAL e^^TecM VGt^tTi

S^UiHC^ ^ ISO

ddcKM

y

r^

l^tO Km

LOCAL

LA

TIT

UO

e(0

«g

.)

S»

¥S

5^

S

iiiiM

SS

n

5

LA

TIT

UD

E(D

eg.)

8o

SS

8

mm

mm

mm

rn

mrn

^

R¥

»s¥

fK:x

-s-

r\

.5

m

5JJ o sn

<3>

X

«» §

.a «>)

01

I

«•

§ it !? CD

cn

/»

:b. 2 % r-

•>1 II i

I CO

os

LA

TIT

UD

E

8o

»O

Io

'

iO O(O o

I <l»

o

LA

TIT

UD

EI Ul

oat

o

'

«o

o

0 "0 1 r-

-x)

tn 7^

7^

09 ? s tS 5 J

?S

C7t>

)

Ik^

01

-90

-ItO

-♦0

•40

Xo»osp»£Kii fbTsirrifii. (volTs")

UT«6

VrI "*V^—;•V I

.- •J'r.X . .. ^ f^TV V. V

LONGITUDE

UT«6

LONGITUDE

;2o/fV

D)?<FT"

UT*I8

wXl -

LONGITUDE

UT-18

•-.t; ••&•••

LONGITUDE

: 90

)/^ too m/^

£d?UlAi^?<

/,

00

LOCAL TIME

60 KV

(c)

f.i

Z«I.O 20 KV

S00

LOCAL TIME

LOCAL TIME

2 = 1.0

z«l.0

• 18

ATV- SIS K

y^;i^«n/5

AT^ ^/5*o K

V i/oc M/s

Figure 2

V'*'

asLii^^)y

\^o KwA

solar, ohl^12 Z--4.0 20 KV

00

LOCAL TIME

60 KV

^tc/ (b)

'9.

LOCAL TIME

;iow

2 *-4.0

00

LOCAL TMKIC

Z«-4.0

,« 7Z 3d)K

-v/VoK

Tl ^ 3<jK

V loomf^

Figure 3

day=83021 TlGCM Ne^trol 7emperolur« (deg k)LTT = 5.0 2P = 2.0

i \ \ V\ V\ >/V • \ / \ \ \ \ ^ I /

i- \ \ 1 V I

500 m/s-occ "^i^e

History«R0BLE/RGPS9 jADED9

A

de2 ort>it-8121(S)

18

U32e-M)3

1 1 4^+03

h

9.60e-t^2

?

t

Perimeter latitude—37.5 (tag

DE-2/GBFPIAVERAGE NEUTRAL WINDS

DEC 1981

305 M/S

NCAR/TGCMMODEL PREDICTIONS

\ \ s S , yyiV. t - "fji/

11=00

333 M/S

A"./ I ' ' I ' ' /^\

A?

\ \ N- - ,\ V-,

\^' *-^ ' i. • ' • • . i;.5> / ^->--1 " y

ls>0 KV '

UT«o ]

-90

-120

(o)

UT.|2

-30

X % ^

t. • / •- • •" ' •• • \> • " ^ - •# • T f A \ "-«0 / ^ . • • # • * \

X # I » V s. / '20

Heo

tONGITUOe

V ^ ^

"30) KM

|uT.6^-30

-/

r . \^t / ^ r-*'' *

Cb)-180

longitude

-90 -. * ' ^ /Ilr^ *

• • • • ^ A/ I , ♦

v/ A'' 'i/ili;;-eo

(c)

a-190

LONGITUDE

if90 -so

-120

(4)-180

LONGITUDE

TI OAt FbHe-iHd S ^PSSSN atJt. I9tcl

gu-l

^RFAce ^

;rA/Aigr/gAl5 (^emi-DiiARhlhL. ^

2-2.

a-^p-d ^

^Pe<LtFy AMpUTUOcS

and P/fASfi"5

fciKt^es i v/A^-ijrcs - s*fMO/fs

ADt>£3^

(F^)R6£S s't: al. ./953.')

MAJOR CONSTITUENT TRANSPORT

The three major neutral constituents of the thermosphere - Oq >^ -^2 " consideredand used to define the ma<ss mgLving fatio pf rnn«gt.i|,iipnt t as

rpi = Tii m, Ey=i

-1

where n,- is the number density of the 2th species, with i = 1, 2 and 3 corresponding,respectively, to O2^ O , and N2', rn- is the mass of the i th species. We furthermore definemixing ratios of O 2 and 0 as the vector

V'O.

and therefore by definition the N2 mixing ratio is obtained by — 1 - V'Oo ~ •

+ e. d

dz

^ rt=-e'r^ ^ m 00

0.25

a^L]kdt

K{z)e

dz IUn.

OtFFu^tci)V

+ S-R.

/TDfty f V£^.]At>V

d 1 , 1 dmV • + w

oz

Upper Boundary Conditions

\t the upper boundary condition, diffusive equilibrium is assumed so that L ^ = 0.

Lower Boundarv Conditions

At the lower boundary, we utilize the observation that the atomic oxygen concentrationi. (0 ) peaks near 97 km and assume that dn {O )ldz =^0. This assumption and conserva-

tion of total oxyg^ atoms implies "oxygen atoms implies

d

dz ^2 — A -I- ^2 = constant

6— P}^CTcT>i56cA.iP,TlcN

^ ^ ^ m > O^. + H

EClui/^CX -EARTH

UT = 12.00 3^90. I I —r-T

60.

30.LJO3f- 0. -

-30.

-60.

-90.

Z = 2.0

-tao. -150. -120. -90. - 30. 0. 30.

LONGITUDE

90. 120. 150. 18C

UT = 12.00 ia.0

90.

60.

30. -

I- 0. W

-30.

-60. ^

-90.-180. -150. -120. -90. -60. -30. 0. 30.

LONGITUDE

400

Z = -4.C

60. 90. 120. 150. 180.

100 M/S

^ n, (0 m/:

^ ^ W/s

«CR»DldA/A«. U)iNrs fM/$\riELD-* *•

• • • • I• • » » %%♦ »o , * %

« % « • « %

nuK

»<

\

«?• •• 9

^tiAL, Ufin!> /<h/s\riELO«U ^ ^ 1T.5N

*. PvSo

•

10C*L 1l«tm.mt cPi<M> mimrn. m • »«it.>i*

ON(S^

n

v*M'o\

/JM-

/O'a

y\)./

(Cfe)N

.ON

N^

9\3

N

T

N4S»)H

(fy\?A^

.1M

WP^^Xi.

I K/V

Neutral-Neutral Coastitaent Reactions and Rates used in the Model.

nCs) + 02

sCd) + Oj

f/(^S) + li/0

N^D) + 0

NQD) + t

N(^D) + NO

NCD)

NO +lkv

NO +ky\t,.

O + 0 +M

O + 0, + M

Reaciioas

fix

03

A

07

A

Tfl

T2

NO + 0 + lAeV

NO + 0('D) + l.84«l'

N. + O + i.«SeV

NCS) + 0 +2.38eV

N(*S) + e +tMeV

N2 + O + S.63<V

N{*S) + hv

WfS)+0

m* + e .J

O n+ O

Oi + M

\iO.

C

MINOR CONSTITUENT TRANSPORT

±-Fdz •" m

Molecular and Thermal Diffusion

Y ' LJdz

Transport Source &

Sink

5^1 dmdz m dz

Eddy Diffusion

where

= gravitational forces + thermal diffusion -h frictional

interaction with major species

Upper Boundary Conditions

Diffusive Equilibrium:

dz "

Lower Boundary Conditions

N {^S) Photochemical Equailibrium

NO Specified Mass Mixing Ratio

V-m =<5

m

i.-D <^Lo5^L

I

200 300 400 500 600 TOO 3 4 5 6 7 8 9 10 11 12 13 14 15 |6TEMPERATURE CK) LOG.o (Owtit,, cm"')

' M I I I I M I M I I I M I I M I I I U

I 2 3 4 5 6 7 8 9 10 II J2 13

L06|o (Density; cm"')

Nrs) :

3.0 4.0 5.0 6.0 7.0

LOG|o (Densityj cm'^)

ISO m

150 m

PHOTOEiKTFRONHEATMG

HEATMG90WHEUVML

CHEMISTRY

HEATWG iWn COUSIONS

4

NEATMGOleOOMBMATION

MMOR

•PECCSIMFFUSION

N(«0).MrS)NO

MEATMQ NBiTRAI^CUTRALCHEMSTRY

iir(K)EQWHO]/i (STdRiM - ^a\sr ^

7cKyf — fi-OKV

TICCU NEUTRAL TCMPnUTinK (BBC K) 4. 5/^TJT - 0.00 ZONAL MEAN (Diftamn) r\

1YCCM 02 NUMBER DENSITY (CM-3) M 3CC/^m « 0.00 ZONAL MEAN (X Differcoec) 'C

-90 •60 -90 • »Uimsx (KG)

k;

M

^CCII N2 NUMBER DENSITY (CM-3) ^bOCTftVT - 0.00 ZONAL MEAN (% Difference)

7 //'/r-.

UTirUDE (DEC)

-30 0 »UT1TUDE (DEC)

„ _ 0 NUMBER DENSITY (CM-3)or - §.00 ZONAL MEAN (X Difference)

UT1TUDE (DEC)

l\).

FIGURE 6

(t)

r

/

O + EQUATION WITH HORIZONTAL AND VERTICAL TRANSPORT

dn

at- Q + Ln = - SZ • nV 1

•where V =Y^+V^

b •^ (ff - SZ p,) +i •uPi1/

B•E Xb

72?

"b

now, —V • nV0= b^ d ^ g-6D 5 r + — n

az "

(^•u)n S. b- b.' S.{b ' u n)

IZ'v^=B X E •SZ(«/B2)

Upper Bcwimdarv Comdations

Mixed boundary condition

-b.^Djm,-

52 ' ifc

Lower Boundary Conditions

Photochemical equilibrium

n (E XB),n + n {b'u)b^ H ^

n=Q/L

andNQ-*-

Once the O"^ distribution is determined the 0 ^ , N^ , N'^ and NO"^ equations are solvedsimultaneously assuming photochemical equilibrium with the O'^ distribution. From thechemistry specified, the production and loss terms are equated and a fourth order equation for

can be derived:

where

n, = n (0+) + n {O^ ) + n {N^ ) + n (iV+) + n {NO'')

Oj = a, (ttj ^ + ttj (7) - ttj Oj a, (f +(?)

O2 — EC •*" Ofj (o^2 E ^ ttj C ) ) —Q!| Of2 ^ —Qfj Qfj B —OC2 Qf3 A

<t 1^ —ot| [EO {^F ) + DC + BE —0C2 E (j4 +Z? ) —03 C +5)

Aq —EC (A + ^ )

A (0+) n (ATj) + n {N+) n (Oj) + fign [NO)

B = ,, (Oj+ ) + *1 n (0+) n (Oj) + itg n (N+) n (Oj)

C =k^n {N (*5)) + fcj n (NO)

D =.j{N2+)

=tj« (0)

F = n (0+)

G =n {N+).

The qfuartic equation can be solved exactly yielding four roots. Three of the roots are imaginary or not physical leaving one real and physicaJ root, for the electron density, . Oncen, is known, the ion number densities can be determined from

n (N2+) = D/iE +a^n,)

n (02+) = B/(C7 +a2nj

n [N0+) = (X + ED /{E +a^n,) + CB /{C + n, Ma^ n.)

(Ar+) = n {N+)/({ks + ifc,) n (Oj) + Ag n (O)).

UT=12; 0

t

-tftO. -120

ilo9io(n,\em-*))

0.

longitude

12LOCAL TIME

17.5N

400.

500.

200.

100.

oQ-

5

4

1

0

-1

-2

-3

-4

-5

-6

-7

LOG TGCM ELECTRON DENSITY (HIST) (CM-3)76080 EQSN03.N04 UT=19.00|sLT=16.00l LON= -45.00

- 400

88

- 300

- 200 o

- 100

-90 0 30GE0G LflT (DEG)

TIGCM OUTPUT

• Neutral gas temperature, Tn

• Neutral winds, U, V, W

• Height of constant pressure surface, h

• Neutral composition and density

Major - O, O2, and N2

Minor - N{^D), N(*S), NO, He, and Ar

• lom coamupositiom

0+, N0+, 0+, and N+ Enj =

loiQ temnperaiture, Ti

E}lectron temperature,

• Global dynamo TT£ —

e , J

CO

Eo

ooO)

E-x:

tsl

0

- ^ 1,1——^——A

1 -

, JVw

Jt L_

—- « • « r~»

' . i— ' • « '—• '•

)r-^

A A- - « — -—t , « . .—^—• • •—

W lOOO

U1

<

12 14

Univer&al Time

• Cbft

1900 M/S -> (d)

TtfC

.

2900 M/S

2900 M/S>

llJ

<

UTs 8:90 MUt 1WC I70CI< irr. U-'iO iCCJH TMC

%

1400 M/S

UT = 15:30 «rca0:90

X

MOO M/S

B

2400

1600

800

00 2 4 6 8 10 12 14 16 18 20 22 24

UT

uTse^so

7^

%^(4co

UT = 15=30

IjJ -u

7^ 3oeK

UT « 12*30

UT = 20=30

LOCAL TIME

4

LOCAL time

12

"TjJ ^ CooK3S&K

TIGCM INPUTS FOR MARCH/APRIL. 1979

83 64 85

DAY OF 1979

ELECTRON DENSITY (CM-DAY=79081 UT=15.00 ZP=

3)

NEUTRAL TEMPERATURE (DEG K) ^DAY=79081 UT= 16.00 ZP= 2.0

-900 6 12 18 0

LOCAL TIME

1 1 I I

1050. 1425. 1800."T T"

.-1 i 1 1 > 1

ni

7

KP

079 DAY

i r.1

89

ATOMIC OXYGEN (CM-3)DAY=79088 UT= 6.00 ZP=-4.0

ji;

i'

SETA-2 ORBIT 1026 DAYS 82194-82195 AVE ALT 22440( 261 POINTS FROM UT 22.75 to 24.23)

90

60 -

OW 30

Q 0D

H-30

;3-60 I-

-90

.,.X23.6

-180 -120 -60 0 60

LONGITUDE (DEG)120 leo

11x10-•13

10X10-•13

CO9x10- 13

SIo 8x10-•13

\

2: 7x10-•13

o

6x10-•13

>-

h-5x10-•13

CO 4x10- 13

zLiJ 3x10- 13

o2x10- 13

10"13

LOCAL TIME

ALTITUDE

22.8 23.0 23

1

.2 23.4 23.6

UT (HRS)1 1 1

23. B 24.0

1

24.2

1 1 1

1 1 1

22

1 1

201612

1 1 1

10

1 1

86 2

1

275 260 245 230 215 200 185 185 215 245 275

SETA-2

(solid)

MSIS66

(dashed)

TIGCM

(dash-star)

SETA~1 ORBIT 180 DAY 79086 AVE ALT 201.32( 204 POINTS FROM UT 19.99 to 21.14)

"T ' ' 1 ' ^

20 30

U 30

f—30\

21.03

-180 -120 -60 60 120 180

11x10- 13

10x10" 13

n9x10-•13

21O 0x10" 13

£ 7x10 13

o13

6x10>-

»- 5x1013

cn 4x10-•13

zLiJ

o3x10- 13

2x10-•13

10'-13

LONGITUDE (DEC)

20.0 20.1 20.2 20.3 20.4 20.5 20.6 20.7 20.8 20.9 21.0 21.1

U1 (HRS)

I I I I 1LOCAL TIME22

ALTITUDE245 230 215 200

2016 12

I

185

10

J_ J L

170 170 185 200 215 245

SETA-1

(solid)

MSIS90

(dashed)

TIGCM

(dash-star)

PCnC

EN

To

rto

tal

po

ints

Pcn

ccN

To

rto

tal

po

ints

Su

UkJt ^

0 ,4^—

•iti

?•

+

? .^ . . . .+ TiPiS^6ci^ A'—-^ '

tf4^ ^ ••««^ '̂ «~ .

^ ^/^%. I ^/^X. ®

J'̂ *»««^*^*'̂ '*'<» •<i»

f I •! |l^ I < r

^ g, . ♦