Analysis of methane columns in the subarctic atmosphere from Poker Flat, Alaska!

The primary objective of this project is to develop an understanding of seasonal and interannual variability in the column abundances of atmospheric methane (CH4) in a subarctic Boreal environment. In a joint US-Japanese project, direct-sun infrared spectra from Poker Flat were recorded from 2000 to 2010 using a ground-based Bruker IFS120HR spectrometer. These data will be analyzed to determine column-averaged methane mixing ratios, which will be assembled into a time-series for the ten year period. Climatology data will be used to explore possible causes of trends and anomalies identified in the time-series. Finally, ground based data from Poker Flat will be compared to those collected by the Japanese satellite, GOSAT/TANSO, and the European satellite, SCIAMACHY for overlapping time periods. NASA has invested in space-based greenhouse gas monitoring through the Orbiting Carbon Observer program (OCO and OCO-2), which are similar to the GOSAT/TANSO and SCIAMACHY satellites. Therefore, the comparisons made between the Poker Flat data we propose to analyze and contemporaneous satellite-based data should inform possible issues for the currently orbiting OCO-2 NASA mission.