air quality forecast in santiago, chile pablo ulriksen and manuel merino centro nacional del medio...

Air Quality Forecast in Santiago, Chile

Pablo Ulriksen and Manuel Merino

Centro Nacional del Medio Ambiente

Universidad de Chile

GURME Air Quality Forecasting WorkshopSantiago, Chile 13-16 October 2003

Air Pollution in Santiago

• Geographical location

• Meteorological conditions

• Urban population and activities

Geographical location

Los Andes-San Felipe

Hijuelas

Casablanca

Q uilapilun

Buin

G raneros

Q uinta de T ilcoco

San Pedro-Bucalem u

-72.0 -71.5 -71.0 -70.5 -70.0

-34.5

-34.0

-33.5

-33.0

-32.5

ENTE

LPLA

CHAD

CODI

LDOR

LPRA

MALLEMAN

LREI

PAIC

Santiago City Area

Climate

Santiago *

http://www.atmosfera.cl/

Anticyclon subsidence inversion

Fig. from R. Sanguineti, CONAMA

Surface Wind, Winter afternoon

-71.4 -71.2 -71.0 -70.8 -70.6 -70.4-34.0

-33.8

-33.6

-33.4

-33.2

-33.0

LPLAMALL

PIRQ

QUIL

LREI

EMAN

PAIC

POLP

LCAÑ

LTIL

LPIN

CODI

MPIN

PAIN

1 m/s

Viento promedio Mensual Julio 1999, 12:00 a 14:45 Hrs

Surface wind, Winter night

-71.4 -71.2 -71.0 -70.8 -70.6 -70.4-34.0

-33.8

-33.6

-33.4

-33.2

-33.0

LPLAMALL

PIRQ

QUIL

LREI

EMAN

PAIC

POLP

LCAÑ

LTIL

LPIN

CODI

MPIN

PAIN

1 m/s

Viento promedio Mensual Julio 1999, 03:00 a 05:45 Hrs

Santiago City Statistics

Metropolitan Region

• Population 6 038 974 (40% Country)

Santiago City

• Population 5 392 840

• Houses 1 473 735

• Daily trips ~ 8.8 million/day

• Vehicles ~ 950000 (56 % catalytic)

Santiago City Statistics

Labor Force Activities, Santiago Metropolitan Region, 2001• Agriculture 3.6 %

• Industry 17.2 %

• Construction 6.8 %

• Transport 8.1 %

• Commerce 21.2 %

• Finantial Services 12.0 %

• Social and Professional Services 30.2 %

• Mining 0.4 %

• Elec, Water, Gas 0.5 %

Air Quality Standards Exceedance during 1995

020406080

100120140160

Da

ys

TSP CO 1 h

O3PM10 CO 8 h

Air Quality in Santiago City

Maximum AQI values during 1995

Air

Qu

alit

y In

dex

PM10 O3 CO SO2 0

100

200

300

400

500

600

Air Quality in Santiago City

PM10 Monthly Averages, Santiago, Chile, 1988-2002(Dicothomous Samplers)

40

80

120

160

200

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

Year

PM

10 (

ug

/m3)

PM10 Daily Maximum Values, 2001Santiago, Chile (MACAM stations)

0

50

100

150

200

250

300

1-J

an

-01

1-F

eb

-01

1-M

ar-

01

1-A

pr-

01

1-M

ay-

01

1-J

un

-01

1-J

ul-

01

1-A

ug

-01

1-S

ep

-01

1-O

ct-0

1

1-N

ov-

01

1-D

ec-

01

Date

PM

10 (

ug

/Nm

3)

Air Quality Standard

Level 1 Alert

Level 2 Pre-Emergency

Promedios horarios mensuales de MP10TEOM-Estaciones Red MACAM, Julio - 1999

0

50

100

150

200

250

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Co

nce

ntr

aci

ón

g

/m3

Providencia

La Paz

La Florida

Las Condes

PO

Pudahuel

Cerrillos

El Bosque

PM10 Air Quality Standard and Episode Levels

PM10 Air Quality Standard (24 h period): 150 ug/m3N

Episode Levels related to PM10 24h concentrations:

Level 1 (Alert) 195-239 ug/m3

Level 2 (Pre-Emergency) 240-329 ug/m3

Nivel 3 (Emergency) 330 ug/m3 or higher

Definición de Índice de Calidad del Aire para Partículas ICAPy Niveles que definen condiciones de Episodio

Con

cen

trac

ión

MP

10 (

g/m

3 )

ICAP

400

300

200

100

100 200 300

Preemergencia

Emergencia( > 330 g/m3 )

500400

Alerta

Norma de Calidad (150 g/m3 )

Bueno a Regular

Meteorological Conditions Related to PM10 Episodes (J. Rutllant and R. Garreaud, 1995)

Episodes Type A (Anticyclonic conditions, Coastal Low)

Episodes Type BPF (Pre-Frontal Conditions)

Episodio Tipo AMapa de 500 hPa

Episodio Tipo AMapa de Superficie y Espesor 1000-500 hPa

Radiosondeo Quintero 17 Mayo 1998- 08 hora local-A

Temperatura y H.R. en Lo Prado

Episodio Tipo BPF Mapa de 500 hPa

Episodio Tipo BPFMapa de superficie y Espesor 1000-500 hPa

Quintero 08 Abril 1998- 08 hora local- BPF

Ocurrencia de episodios Tipo A y BPF (Abril-Sep 1997-2003)

37

18

25

15

24

12

26

10

25

4

29

8

29

12

0

10

20

30

40

NºD

ías

97 98 99 2000 2001 2002 2003

Años

Episodios Tipo A y BPF

Tipo A

Tipo BPF

Condiciones Meteorológicas y MP10

Epi

sodi

os

Alta

del

Pac

ífic

o

Ines

tabi

lidad

post

-fro

ntal

Act

ivid

ad

fron

tal

0

20

40

60

80

100

120

140

160

180

200

PM

-10

PR

OM

ED

IO

Epi

sodi

os

Tip

os A

y B

PF

Alta

del

Pac

ífic

o

Ines

tabi

lidad

post

-fro

ntal

Act

ivid

ad

fron

tal

Temperatura y H.R. en Lo Prado

Episodio Pudahuel 26 Junio 2001

Episodio 26 Junio 2001PMCA, concentraciones horarias MP10 e ICAP en Pudahuel

0

100

200

300

400

500

600

700

010020010624

010020010625

010020010626

010020010627

010020010628

Hora Fecha

ug

/m3-

ICA

P

EL(ug/m3)

EL(ICAP)

Meteorological Index (PMCA)

Air Pollution Meteorological Potential (PMCA) related to PM10 in Santiago(Represent an inverse of Ventilation factor)

5 Index Classes: 1 Low2 Low to Medium3 Medium4 Medium to High5 High

Each Index Class is associated to one or more synoptic and mesoscale configurationsUpper air variables ranges associated to each Index Class.Meteorological conditions follow up and analysis support expert forecast.

Meteorological Index Classes

Class 1 Low

Active Frontal Systems

Intense Instability

Class 2 Low to

Medium

Frontal Systems

Instability

Intense Humid Air Advection

Segregated Cold Lows

Class 3 Medium

Anticyclone Conditions

Light Humid Air Advection

Class 4 Medium to

High

Type A Episode

Type BPF Episode

Medium Zonal Circulation

Index

Class 5 High

Intense Type A Episode

Intense Type BPF Episode

Low Zonal Circulation

Index

Episode Conditions

Meteorological Index Classes

Objective Classification Rules based on selected upper air forecasted variables

Geopotencial Height 500 Hpa

5400

5500

5600

5700

5800

5900

1 2 3 4 5

Meteorological Index (PMCA) for PM10

Hei

ght (

m)

-1 desv. Est

promedio

+1 desv. Est

Temperature 925 hPa

0

5

10

15

20

25

1 2 3 4 5

Meteorological Index

Te

mp

era

ture

(C

)

-1 desv. Estpromedio +1 desv. Est

Dew Point Depresion 925 hPa

0

5

10

15

20

25

30

35

40

1 2 3 4 5Meteorological Index

De

w P

oin

t D

ep

res

(C

)

-1 desv. Est

promedio

+1 desv. Est

Daily Meteorological Index (PMCA) and PM10 time series

PMCA observado vs PM10

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

31-m

ar

4-a

br

8-a

br

12-a

br

16-a

br

20-a

br

24-a

br

28-a

br

2-m

ay

6-m

ay

10-m

ay

14-m

ay

18-m

ay

22-m

ay

26-m

ay

30-m

ay

3-jun

7-jun

11-jun

15-jun

19-jun

23-jun

27-jun

1-jul

5-jul

9-jul

13-jul

17-jul

21-jul

25-jul

29-jul

2-a

go

6-a

go

10-a

go

14-a

go

18-a

go

22-a

go

26-a

go

30-a

go

970903

970907

970911

970915

Fecha

PM

CA

0

50

100

150

200

250

300

PM

10 PMCA

PM10

Air Quality Forecasting System for Santiago

Forecast Requirements:

• Next day PM10 maximum 24 h value estimated at each monitoring station

• Forecast Accuracy > 65% at each monitoring station

• Independent expert validation

• Operational considerations: – Report episode levels not forecasted

– Report changes in meteorological conditions that affect episode declarations

– Report monitor stations perturbations that affect representativity

Air Quality Forecasting System for Santiago

CENMA Air Quality Forecast Program:• Use all the information and forecast tools available • Operational use of forecast tested methods• Final forecast decision by expert meteorologist• Assure timely report deliver• 2 persons (at least) dedicated every day, 7 days per week• Permanent interaction with counterparts• Permanent internal evaluation of analysis and forecast

results • Search Expert Evaluation and Recommendations

Air Quality Forecasting System for Santiago

Conceptual Squeme

Meteorological ConditionsSynoptic and Mesoscale

Meteorological ConditionsBasin and Urban Scale

Air Quality

Emissions

Meteorological ConditionsSynoptic and Mesoscale

Meteorological ConditionsBasin and Urban Scale

Air Quality

Emissions

Meteorological Index (PMCA)

Present (Observed) Conditions

Future (Forecast) Conditions

Air Quality Forecasting System for Santiago

Meteorological ConditionsSynoptic and Mesoscale

Meteorological ConditionsBasin and Urban Scale

Air Quality

Emissions

Present (Observed) Conditions

Synoptic Weather Analysis ChartsSatellite Images (GOES)Nearest Radiosonde (Santo Domingo, DMC)Surface Synoptic Stations (DMC)

CENMA Regional Meteorological Network (12 Surface Stations, 1 Vertical Profiler LAP-RASS)Santiago Air Quality Network (7 sites)

Santiago Air Quality Network (8 sites)

Data Sources

Air Quality Forecasting System for Santiago

Meteorological ConditionsSynoptic and Mesoscale

Meteorological ConditionsBasin and Urban Scale

Air Quality

Emissions

Numerical Weather Forecast Models:NCEP (AVN), NOGAPS, ECMRFETA (CPTEC Brasil), MM5 (U.Chile)

CENMA Local Scale Meteorological Forecast (Meteorological Index, PMCA)

Statistical Model (J. Cassmassi)

Future (Forecast) Conditions

Day of Week Air Quality Variation

Data Sources

Regional Meteorological Network supporting Air Quality Forecast

Continuous monitoring:•PM10•CO•SO2•NOx•O3•HC•Meteorology

Air Quality Monitoring Network in Santiago (MACAM2, 1997 )

Air Quality Forecast Model

PM10 Forecast Model for SantiagoDeveloped by J. Cassmassi (SCAQMD, California)

Statistical relationships obtained by Multilinear Regression, PM10 maximum 24h values estimated for each monitoring station, one day in advance.

Variables: – Observed: upper air meteorology, PM10 concentrations, week variation of

PM10 (subrogate for emission variations)– Forecast and observed: Meteorological Conditions Index (PMCA)

Data period:– Model Development: 1997-1998, April – Sep– Model Validation: 1999, April – Sep

Independent evaluation: H. Fuenzalida, U. de Chile

Meteorological Index Forecast Evaluation

Air Quality Forecast Evaluation

Forecast 5 Index Classes 1998 1999 2000 2001 2002 Perfect Agreement (Deviation 0), one day in advance

79.7 % 79.9 % 83.2 % 84.7 % 80.2 %

Perfect Agreement (Deviation 0), two days in advance

72.9 % 65.5 % 70.2 % 71.2 % 69.5 %

Agreement considering +/-1 class deviation, one day in advance

99.7 % 99.7 % 99.4 % 99.7 % 99.5 %

Air Quality Forecast Evaluation

Air Quality Forecast Model Evaluation

4 Air Quality Levels Forecast 2000 2001 2002 2003 Perfect Agreement (Deviation 0) (%) 74.7 85.9 80.2 76.1 Episodes Not Alerted (%) 23.5 25.0 16.0 33.3 False Alerts (%) 51.9 48.3 55.3 57.1

•General agreement of observed and predicted values

•Over–prediction of Episode Level 1 Alert (False Alerts)

Air Quality Forecast Evaluation

MP10 pronosticado por la ecuación N° 1 del Modelo Cassmassi, valor observado y Opinión Experta entre el 15 de Marzo y 17 de Septiembre 2002

0

50

100

150

200

250

300

15-M

ar

25-M

ar

04-A

br

14-A

br

24-A

br

04-M

ay

14-M

ay

24-M

ay

03-J

un

13-J

un

23-J

un

03-J

ul

13-J

ul

23-J

ul

02-A

go

12-A

go

22-A

go

01-S

ep

11-S

ep

ug

/m3

0

50

100

150

200

250

300

ug

/m3

MP-10 Pronosticado MP-10 Observado

Alerta Preemergencia

Opinión Experta Emisiones Locales

PM10 Observed and Forecast Values, March-Sep 2002

Air Quality Forecast Results

118114

10196

8184

93

0

20

40

60

80

100

120

140

PM

10

ug

/m3

1997 1998 1999 2000 2001 2002 2003

Year

PM10 Mean Concentration (01 Abril- 17 Septiembre), 1997-2003Air Quality Monitoring Stations, Santiago

PM10 Mean Concentration Increase last years

Air Quality Forecast Results

PM10 Episode days Increase last years

MP10 Máximos Diarios 1997-2003 (01 Abril-17 Septiembre)

99 102

8879

67

28

4449 45

3238

25 24

11

36

1913 10 7 8 43 1 1 0 0 0 0

4958

3141

34

1622

0

20

40

60

80

100

120

1997 1998 1999 2000 2001 2002 2003

Años

N°

Día

s

>150 >150 y <=195 >195 y <=240 >240 y <=330 >330

Discussion

Meteorology Index Forecast shows good perfomance

Posible improvements:

• Refined NWP models for this Region

• Continue meteorology - air quality relationships analysis

Air Quality Forecast:

• Adjust statistical model to air quality scenario changes

• Test other approaches (MOS, neural network, pattern classification, ...?)

• Study Santiago North West Sector, where highest PM10 levels are observed.