Read Full Article (file size: 2641605 bytes)    Cited by

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 108, NO. D17, 4537, doi:10.1029/2003JD003453, 2003

Global inventory of nitrogen oxide emissions constrained by space-based observations of NO₂ columns

Randall V. Martin

Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA

Daniel J. Jacob

Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA

Kelly Chance

Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA

Thomas P. Kurosu

Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA

Paul I. Palmer

Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA

Mathew J. Evans

Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA

Abstract

We use tropospheric NO₂ columns from the Global Ozone Monitoring Experiment (GOME) satellite instrument to derive top-down constraints on emissions of nitrogen oxides (NO _x ≡ NO + NO₂), and combine these with a priori information from a bottom-up emission inventory (with error weighting) to achieve an optimized a posteriori estimate of the global distribution of surface NO _x emissions. Our GOME NO₂ retrieval improves on previous work by accounting for scattering and absorption of radiation by aerosols; the effect on the air mass factor (AMF) ranges from +10 to −40% depending on the region. Our AMF also includes local information on relative vertical profiles (shape factors) of NO₂ from a global 3-D chemical transport model (GEOS-CHEM); assumption of a globally uniform shape factor, as in most previous retrievals, would introduce regional biases of up to 40% over industrial regions and a factor of 2 over remote regions. We derive a top-down NO _x emission inventory from the GOME data by using the local GEOS-CHEM relationship between NO₂ columns and NO _x emissions. The resulting NO _x emissions for industrial regions are aseasonal, despite large seasonal variation in NO₂ columns, providing confidence in the method. Top-down errors in monthly NO _x emissions are comparable with bottom-up errors over source regions. Annual global a posteriori errors are half of a priori errors. Our global a posteriori estimate for annual land surface NO _x emissions (37.7 Tg N yr⁻¹) agrees closely with the GEIA-based a priori (36.4) and with the EDGAR 3.0 bottom-up inventory (36.6), but there are significant regional differences. A posteriori NO _x emissions are higher by 50–100% in the Po Valley, Tehran, and Riyadh urban areas, and by 25–35% in Japan and South Africa. Biomass burning emissions from India, central Africa, and Brazil are lower by up to 50%; soil NO _x emissions are appreciably higher in the western United States, the Sahel, and southern Europe.

Received 27 January 2003; accepted 7 April 2003; published 5 September 2003.

Index Terms: 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; 0394 Atmospheric Composition and Structure: Instruments and techniques; 1640 Global Change: Remote sensing.

Read Full Article (file size: 2641605 bytes)    Cited by

Citation: Martin, R. V., D. J. Jacob, K. Chance, T. P. Kurosu, P. I. Palmer, and M. J. Evans (2003), Global inventory of nitrogen oxide emissions constrained by space-based observations of NO₂ columns, J. Geophys. Res., 108(D17), 4537, doi:10.1029/2003JD003453.

Copyright 2003 by the American Geophysical Union.