Estimation of Emission Sources Using Satellite Data

Randall Martin

General Approach to Infer Emissions from Satellite Observations General Approach to Infer Emissions from Satellite Observations Error Characterization Major Area for Further ImprovementError Characterization Major Area for Further Improvement

Some Practical Issues– model at resolution of desired inventory– appropriate independent observations– nonlinear methods

Bottom-up emissions xa & Errors Sa

Optimized inventory x & Errors

Test with independent observations

F(x)

Satellite obs y Forward model F(x) & Errors Sy

( ) ( T TJ -1 -1y a a ax y F(x)) S (y -F(x)) + (x - x ) S (x - x )min

Error covariance matrices for – bottom-up inventory Sa – satellite retrieval Si

– forward model Sm

– representativeness Sr } Sy

Specific Approaches Often Depend on Species LifetimeSpecific Approaches Often Depend on Species Lifetime

1015 molec N cm-2

Species Lifetime Issue

NOx ~hours - day

Representing NOx lifetime (chemistry)

HCHO & isoprene

~hours Identifying HCHO source

CO ~month Accounting for transport

SCIAMACHY Tropospheric NO2 OMI HCHO

Chance & Kurosu

MOPITT CO

MOPITT Team

Martin et al., submitted

SCIAMACHY NOx Emissions (2004-2005) East Asia Becomes Dominant Emitter (50% increase) Resolution?

GOME Isoprene Emissions (1998) Within ~10% of MEGAN

MOPITT CO Regional EmissionsMartin et al., submitted

Palmer et al., 2006

Heald et al., 2004

May

Jun

Jul

Aug

Sep

… … and Have Yielded Promising Resultsand Have Yielded Promising Results

In Situ Measurements Support Satellite-based InventoriesIn Situ Measurements Support Satellite-based InventoriesAdditional Measurements Critical for Inventory EvaluationAdditional Measurements Critical for Inventory Evaluation

In Situ

GEOS-CHEM (A priori)

GEOS-CHEM (A posteriori)

NOAA P-3 Measurements (Ryerson, Flocke, Neuman)

Palmer et al., 2003

GOMEr2 = 0.77

Martin et al., submitted

Pfister et al., 2005

GEIA (A priori)r2 = 0.53

Thorough Validation of MOPITT CO Thorough Validation of MOPITT CO Validation of NOValidation of NO22 and HCHO Where Possible and HCHO Where Possible

Remaining Issues in Temporal Variation and Subpixel Variability Remaining Issues in Temporal Variation and Subpixel Variability

r = 0.79 slope = 0.8

Ryerson (WP-3D)Cohen (DC-8)

Martin et al., submitted

Emmons et al., 2004

Martin et al., 2004

In Situ NO2 (1015 molec cm-2)S

CIA

MA

CH

Y

NO

2 (10

15

mol

ec c

m- 2)

ICARTT

Discrepancy in Wintertime GOME NODiscrepancy in Wintertime GOME NO22 Columns Over Industrial Regions Columns Over Industrial Regions

Need to Better Understand Retrieval and Model ErrorsNeed to Better Understand Retrieval and Model Errors

Europe

Eastern US

van Noije et al., submitted

Year 2000

CO, VOCs, NOx

HO2OH

NONO2

H2O2

O3

hv, H2O

hvHNO3

OH

VOCs

Develop Simultaneous Inversion for Local CO, NOx, VOC Emissions from Observations of NO2, HCHO, CO, O3, HNO3

Will Require Iterative Solution (i.e. Adjoint)

NOx

HOx

CO2

HCHO

CO

hv, OH

Value of Spatial and Temporal Resolution of Value of Spatial and Temporal Resolution of Measurement from Emissions Inventory PerspectiveMeasurement from Emissions Inventory Perspective

Species Lifetime Value of Horizontal Resolution

Value Vertical Resolution

Value of Temporal Resolution

Comments

NO2 Hours-day High Medium High Most NO2 near surface, strong horizontal variation

HCHO Hours High Medium High Local urban sources, variable biogenic sources

SO2 ~day High Medium Medium Additional retrieval development

CO ~Month Low-Medium High Medium Critical to Resolve Lower Troposphere

O3 ~days – month

Medium High Medium Critical to Resolve Lower Troposphere

HNO3 ~week Medium Medium Medium Column measurement would be valuable

AcknowledgementsAcknowledgements

Chris Sioris, Thomas Kurosu, Kelly Chance (Smithsonian Astrophysical Observatory)Paul Palmer (University of Leeds)Twan van Noije (KNMI)Andy Neuman, Tom Ryerson (NOAA/CIRES)Ron Cohen, Colette Heald (Berkeley)Louisa Emmons, Frank Flocke, Gabriele Pfister, Aaron Swanson, (NCAR)

Funding: National Aeronautics and Space Administration (NASA)