GEOS-CHEM at the University of Washington

Lyatt Jaeglé, Qing Liang, Linda Steinberger, Sarah Strode, Ricky Sinha

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🡺 Long-range transport of CO and O₃ to the NE Pacific

🡺 Biomass burning in Africa: GOME and SAFARI 2000

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🡺 Global modeling of the mercury cycle

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🡺 Interactive display of GEOS-CHEM results on the web

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U N I V E R S I T Y O F W A S H I N G T O N S C H O O L O F N U R S I N G

U N I V E R S I T Y O F W A S H I N G T O N

DEPARTMENT OF ATMOSPHERIC SCIENCES

Long-range transport of CO and O₃ to the NE Pacific

• Model evaluation with PHOBEA observations in NE Pacific:
• Spring 1997, 1998, 2001, 2002: CO, O₃ [NMHC, NO_x, PAN, Rn]
• Full seasonal cycle Mar 2001-June 2002: CO, O₃

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• Applications:
• Origin of CO and O₃ in NE Pacific: long-range transport from Asia
• Seasonal and interannual variability in long-range transport

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🡺GEOS-CHEM forecasts: ITCT2K2 and PHOBEA-II during spring 2002

Qing Liang

Collaborators: Dan Jaffe and his group at UW Bothell

Duchess aircraft

Cheeka Peak Observatory

Origin of CO and O₃ at Cheeka Peak: Spring 2002

CO

O₃

Very good agreement: Model captures background levels and day-to-day variability in CO

Model underestimates O₃ levels by 7 ppbv and poor correlation

Obs: 149 ppbv; Model: 153 ppbv; r²= 0.68

Obs: 43 ppbv; Model: 36 ppbv; r²= 0.27

Model

Observations

Vertical profiles above CPO during spring 2001�12 Duchess aircraft flights

Model

Observations

CO profiles

O₃ profiles

• Very good agreement for CO

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🡪 BUT for ozone negative bias near surface and positive bias aloft: Strat-trop exchange? N₂O₅ hydrolysis (Temp. dependent)? NO_x emissions?

Seasonal variations of CO in 2001 at CPO

spring 2002

winter

fall

summer

spring 2001

Asia

North America

spring 2002

Biomass burning in Africa: SAFARI 2000

• Model evaluation with SAFARI 2000 observations Aug-Sep 2000:
• UW Convair 580: CO, O₃, SO₂, NMHCs
• Ozonesondes [Thompson et al., 2000]
• Improve biomass burning, fossil fuel, and biogenic emission inventories

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• Applications:
• Origin of haze over Africa
• Export of biomass burning and anthropogenic emissions through the river of smoke (Indian Ocean) vs. to the Atlantic

Ricky Sinha, Peter Hobbs

UW CONVAIR 580

Timbavati fire

P. Hobbs

UW Convair 580 flight tracks and O₃

O₃

UW Convair 580

Longitude

SHADOZ ozonesondes during SAFARI2k

Longitude

Lusaka, Zambia

Model

Observations

Irene, South Africa

SAFARI 2K ozonesondes: Thompson et al. [2002]

Model

Observations

SAFARI’s river of smoke

GEOS-CHEM CO

September 5 2000

TOMS Aerosol Index

Eck et al., 2003

Using satellite observations to constrain biomass burning emissions in Africa: GOME

Linda Steinberger

Collaborators: Randall Martin, Kelly Chance, Paul Palmer

GEOS-CHEM

GOME

NO₂, HCHO columns

Other satellites:

Fires/burned areas (SPOT, ATSR)

Aerosol optical depth (MODIS)

MOPITT CO

Plume studies

Aug-Sep 2000

NO₂ columns in Aug. 2000: GOME & GEOS-CHEM

GOME NO₂

GEOS-CHEM NO₂

10¹⁵ cm^-2

NO₂ & HCHO columns in August 2000

GOME NO₂

GEOS-CHEM NO₂

GOME HCHO

GEOS-CHEM HCHO

10¹⁵ cm^-2

10¹⁶ cm^-2

🡺 Isoprene emissions in GEOS-CHEM too large?

🡺 Biomass burning VOC in GEOS-CHEM too small?

West to East progression in biomass burning during the dry season

GOME NO₂

Burned area

GOME HCHO

Jul ‘00

Aug ‘00

Sep ‘00

10¹⁵ cm^-2

10¹⁶ cm^-2

NO_x emissions over Africa: July-February

Northern Africa (0-30ºN)

Southern Africa (0-20ºS)

Jul Aug Sep Oct Nov Dec Jan Feb

Jul Aug Sep Oct Nov Dec Jan Feb

GOME

GEOS-CHEM

GEOS-CHEM Mercury simulation

Sarah Strode, Igor Kamenkovich (JISAO)

Collaborators: Noelle Eckley, Rokjin Park, Daniel Jacob

• Model development:
• Ocean mercury module
• Biomass burning emissions
• Model evaluation:
• Surface observations networks (Canada, US, Europe)
• Remote sites (Cheeka Peak Observatory) + cruises + vertical profiles
• Applications:
• Role ocean in the mercury cycle
• Long-range transport of mercury from Asia
• Evolution of mercury since pre-industrial times

Development of a GEOS-CHEM ocean mercury module

• Implement air-sea exchange of mercury using temperature and wind-dependent transfer velocities
• Couple GEOS-CHEM with a mixed-layer ocean model: wind-driven advection of Hg⁰/Hg²⁺
• Implement oxidation of Hg²⁺ to Hg⁰ in surface waters (photoch./biol.)
• Investigate rapid oxidation of Hg⁰ in marine boundary layer

🡺 For longer timescale simulations, use a 3-D ocean GCM (MOM 2)

Hg^o

Hg²⁺

Hg_p

Particle

removal

Hg²⁺

Hg^o

Net evasion

Marine boundary layer

Upper ocean

Free troposphere

Wet & dry deposition

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http://jchemed.chem.wisc.edu/

An interactive web interface to display GEOS-CHEM results: http://www.atmos.washington.edu/~jaegle/geoso3_start.html

• Web interface using ION (IDL On the Net) to access GAMAP and plot GEOS-CHEM fields

• Interactive creation of maps, zonal means, and animations
• Monthly mean fields from O_x-NO_x-NMHC simulations:

4°x5° (1994-1997) and 2°x2.5° (1997)

ITCT2K2 Automatic Processing System (IAPS) interactive web interface

• GEOS-CHEM 5-day CO forecasts transferred from Harvard to UW
• Interactive creation of maps, vertical profiles, timeseries, and animations from the forecast output
• Successful use in the field for flight planning