Greenhouse Gas Observations and Assimilation Methods for Emissions Estimates

Quantifying emissions of greenhouse gases CO2, CH4, and related species (O3, CO, NOx, aerosols) is essential to climate prediction and for evaluating control strategies. Using measurements of these trace species from DISCOVER-AQ and RAMMPP in the Mid Atlantic States we have begun Flux of Greenhouse Gases in Maryland (FLAGG-MD), a project to quantify emissions and associated uncertainties of these climate forcers. The observations can help evaluate the efficacy of climate actions such as the Regional Greenhouse Gas Initiative (RGGI) implemented locally by the Maryland Department of the Environment. Measurements alone, however, are inadequate to determine net and gross GHG emissions. We describe initial results and methods to assimilate these data into Chemical Transport and C-Cycle models using techniques pioneered by Eugenia Kalnay.