Regional variations in atmospheric methane in Argentina according to satellite data

The concentration of atmospheric methane [CH4] is determined by the balance between direct emissions and uptakes, both into and from the atmosphere, as well as by its chemical destruction in the atmosphere itself. For regional studies involving vast areas, remote sensing may be used as now georeferenced [CH4] measurements from satellites are available. However, these correspond to the total atmospheric column and therefore require further elaboration to account for events at surface level. This study presents an analysis of the measurements obtained for [CH4] in Argentina from GOSAT satellite monitoring, for the period October 2009 – September 2012. Once large-scale variations were deduced to be able to estimate local effects, spatial and temporal (seasonal and interannual) variations in [CH4] were analysed. Results indicated an increase in [CH4] throughout the studied period. In addition, three different regions were identified: one behaving as a source, another as a sink, and a mixed area (wetlands, soils, urban areas).