Usability of optical spectrum analyzer in measuring atmospheric CO2 and CH4 column densities: inspection with FTS and aircraft profiles in situ

摘要

The practical usefulness of a desktop optical spectrum analyzer (OSA) formeasuring atmospheric CO and CH column densities at surfacesites was examined in two separate measurement campaigns. The firstcomparison involved operating the OSA in parallel with a high resolutionFourier transform spectroscopy (FTS) situated at the University ofWollongong in Australia. Scale factors for the OSA were assigned for thecolumn average volume mixing ratios of CO and CH by comparingwith the well-studied FTS. The second method is a calibration againstaircraft CO profiles in situ over Tsukuba in Japan obtained during aGOSAT validation campaign carried out from 28 January to 7 February 2011.The CO values in the campaign, deduced by use of a derived OSA scalefactor, were in excellent agreement with the integrated aircraft profiles.