Wednesday, 17 January 2007: 11:00 AM
CH4 in the atmosphere over the peatland ecosystem of West Siberia retrieved from AIRS/AQUA spectra
210B (Henry B. Gonzalez Convention Center)
Methane horizontal distribution and seasonal variation in atmosphere over permafrost sub-arctic zone of West Siberia have been retrieved from AIRS/AQUA spectrum data using an originally developed forward/retrieval model, FIRE-ARMS. The method is based on retrieval of atmospheric temperature profile using AIRS spectra in the range of 680 - 800 cm-1 on clear sky observation spots and then retrieval of CH4 content in total atmospheric column using the spectrum data in the range of 1298 - 1306 cm-1. Main features of the inverse code and estimated error of the methane retrieval scheme are discussed in this paper. The obtained maps of 2D seasonal mean methane content in the atmosphere of the Western Siberia (60-67N; 60-90E) for springs 2004-2005, summers 2004-2005, autumns 2004-2005, winters 2004-2005 and 2005-2006 are presented. The methane maps are combined with seasonal mean tropospheric wind maps for the target area and maps of location of natural gas and oil industries units. In result significant anthropogenic sources of methane emission to the atmosphere such as high pressure pipelines for natural gas transport and gas flares at places of oil obtainment have been identified on the winter methane map in the Western Siberia. Net contribution to methane concentration in the atmosphere due to natural methane emission from the permafrost sub-Arctic zone of peatland ecosystem in summer season is evaluated.