Satellite Observations of Tropospheric Gases and Aerosols

Randall Martin

With contributions from:With contributions from:Rongming Hu (Dalhousie University)Rongming Hu (Dalhousie University)

Chris Sioris, Xiong Liu, Kelly Chance (Smithsonian Astrophysical Observatory)Chris Sioris, Xiong Liu, Kelly Chance (Smithsonian Astrophysical Observatory)Tom Ryerson, Andy Neuman (NOAA/CIRES)Tom Ryerson, Andy Neuman (NOAA/CIRES)

Ron Cohen (Berkeley)Ron Cohen (Berkeley)Aaron Swanson, Frank Flocke (NCAR)Aaron Swanson, Frank Flocke (NCAR)

Space-based Measurements of Tropospheric Composition Space-based Measurements of Tropospheric Composition Related to Both Air Quality and ClimateRelated to Both Air Quality and Climate

Sensor TOMS GOME MOPITT MISR MODIS AIRS SCIA-MACHY

TES OMI CALIOP

Platform (launch)

multi

(1979-)

ERS-2 (1995)

Terra Aqua

(1999) ( 2002)

Envisat (2002)

Aura

(2004)

Calipso

2005

ozone X (low lat)

X X X

CO X X X

NO2 X X X

HCHO X X

aerosol X X X X X X

Retrieval of Tropospheric NORetrieval of Tropospheric NO22 from SCIAMACHY from SCIAMACHY

Spectral Fit

Remove Stratosphere

Total NO2 Slant Column

Tropospheric NO2 Slant Column

Calculate AMF

Tropospheric NO2 Column

Martin et al., 2002, 2005

Martin et al., 2002

Palmer et al. 2001 Martin et al., 2002, 2003, 2005

Mean Total Uncertainty ±(5x1014 molec cm-2 + 30%)

Scattering by Earth surface and by atmosphere

Significant Agreement Between Coincident Cloud-Filtered SCIAMACHY and Significant Agreement Between Coincident Cloud-Filtered SCIAMACHY and ICARTT In-Situ Measurements In Summer 2004ICARTT In-Situ Measurements In Summer 2004

r = 0.78

slope = 0.82

1:1 line

Ryerson (WP-3D)

Cohen (DC-8)

Chris Sioris

Cloud-radiance fraction < 0.5

In-situ measurements below 1 km & above 3 km

Assume constant mixing ratio below lowest measurement

Add upper tropospheric profile from mean obs

In Situ NO2 Columns

NASA DC-8 NOAA WP-3D

SC

IAM

AC

HY

NO

2

Cloud-filtered Tropospheric NOCloud-filtered Tropospheric NO22 Columns Retrieved from Columns Retrieved from

SCIAMACHYSCIAMACHY

May-Oct 2004

detectionlimit

Errorweightin

g

Conduct a Chemical Inversion & Combine Top-Down Conduct a Chemical Inversion & Combine Top-Down and Bottom-up Inventories with Error Weightingand Bottom-up Inventories with Error Weighting

A posteriori emissionsTop-Down Emissions

1015 molec N cm-2

A Priori NOx EmissionsSCIAMACHY NO2 Columns

1011 molec N cm-2 s-1

GEOS-CHEM model

GEIA

May-Oct 2004

Global Optimal Emission Inventory RevealsGlobal Optimal Emission Inventory RevealsMajor Discrepancy in NOx Emissions from MegacitiesMajor Discrepancy in NOx Emissions from Megacities

r2=0.82 vs a priori

In Situ Airborne Measurements Over and Downwind of New In Situ Airborne Measurements Over and Downwind of New York City Support A Posteriori InventoryYork City Support A Posteriori Inventory

In Situ

GEOS-CHEM (A priori)

GEOS-CHEM (A posteriori)

P-3 Measurements Tom Ryerson (NOAA) Aaron Swanson Andy Neuman Frank Flocke (NCAR) (CIRES/NOAA)

Large Change in NOx Emissions Near New York CityLarge Change in NOx Emissions Near New York City

1011 atoms N cm-2 s-1 1011 atoms N cm-2 s-1 1011 atoms N cm-2 s-1

A posteriori A posteriori – A priori

7.8 Tg N 0.6 Tg N

r2 = 0.92

7.2 Tg N

A priori

Liu et al., submitted

Direct Retrieval of Tropospheric Ozone from GOMEDirect Retrieval of Tropospheric Ozone from GOMEUsing Optimal Estimation in Ultraviolet with TOMS V8 Using Optimal Estimation in Ultraviolet with TOMS V8 a prioria priori

GOME GEOS-CHEM

Tro

po

sph

eric Ozo

ne C

olu

mn

(Do

bso

n U

nits)

Aerosol Absorption Contributes to Differences Between Aerosol Absorption Contributes to Differences Between Aerosol Optical Depth and the Absorbing Aerosol IndexAerosol Optical Depth and the Absorbing Aerosol Index

July 2000

1.5

1.1

0.8

0.4

0

3.0

2.2

1.6

0.8

0

July 2000

MODIS

TOMS

Retrieval of Aerosol Single Scattering AlbedoRetrieval of Aerosol Single Scattering AlbedoDetermined with radiative transfer calculation as Determined with radiative transfer calculation as SSA that reproduces

TOMS Aerosol Index when constrained by MODIS aerosol optical depth

Rongming Hu

July 2000

r = 0.8

Slope = 1.01

Intercept = -0.02

AcknowledgementsAcknowledgements

Rongming Hu (Dalhousie University)

Chris Sioris, Xiong Liu, Kelly Chance (Smithsonian Astrophysical Observatory)

Tom Ryerson, Andy Neuman (NOAA/CIRES)

Ron Cohen (Berkeley)

Aaron Swanson, Frank Flocke (NCAR)

Funding:

• National Aeronautics and Space Administration (NASA)

• Canadian Foundation for Climate and Atmospheric Sciences (CFCAS)

• Canadian Foundation for Innovation (CFI)

• Nova Scotia Research and Innovation Trust (NSRIT)