Toward anthropogenic combustion emission constraints from space-based analysis of urban CO2/CO sensitivity

We explore the value of multispectral CO retrievals from NASA/Terra Measurement of Pollution In The Troposphere (MOPITT v5), along with Atmospheric CO2 Observations from Space (ACOSv2.9) CO2 retrievals from the Japan Aerospace Exploration Agency Greenhouse Gases Observing Satellite (GOSAT), for characterizing emissions from anthropogenic combustion. We use these satellite retrievals to analyze observed CO2/CO enhancement ratios (CO2/CO) over megacities. Since CO is coemitted with CO2 in anthropogenic combustion, the observed CO2/CO characterizes the general trend in combustion activity. Our analyses show patterns in CO2/CO that correspond well with the developed/developing status of megacities, and CO2/CO that agree well with available literature and emission inventories to approximately 20%. Comparisons with CO2/CO derived from Total Carbon Column Observing Network measurements show similar agreement, where some of the differences in observed CO2/CO are due to representativeness and limited GOSAT data. Our results imply potential constraints in anthropogenic combustion from GOSAT/MOPITT, particularly in augmenting our carbon monitoring systems.