Constraints on High-Latitude Regional Methane Fluxes Through Integration of Satellite, Aircraft and Ground-Based Observations with Models

The overall objective of the work presented here is to use a regional Lagrangian particle dispersion model (WRF-STILT) to interpret satellite, aircraft and surface observations over North America, with the eventual goal of constraining the wetland methane (CH4) fluxes. Here we will show comparisons of model results with data from a range of platforms, including the Tropospheric Emission Spectrometer (TES), aircraft from NOAA ESRL sites and from the ARCTAS-B campaign and a tower at the Environment Canada site at Fraserdale. Although near-surface sensitivity in the mid-IR is more limited than that from near-IR instruments, TES provides good coverage at high latitudes. We present sensitivity studies using improved TES CH4 retrievals with enhanced sensitivity in the lower troposphere and assess the consistency of the satellite, aircraft and ground-based measurements. Reconciliation between results from different observation platforms calls for an accurate definition of the background CH4 in the model. We also evaluate the extent to which these data can be used to constrain wetland fluxes. Future plans include studies using other satellite CH4 measurements.