Comparison of Orbital and Ground Based Spectroscopic Measurements of CO and CH4 Total Content
Rakitin, Vadim1; Yurganov, Leonid2; Safronov, Alexandr1; Grechko, Evgeny1; Fokeeva, Ekaterina1; Dzhola, Anatoly1; Pankratova, Natalya1
1Obukhov Institute of Atmospheric Physics RAS, RUSSIAN FEDERATION; 2Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, MD, UNITED STATES
The results of regular ground-based spectroscopic measurements of CO total content (TC) over Moscow and Zvenigorod (53 km to the West from the Moscow measurement site) during 2010-2012 and over ZOTTO station (Central Siberia) for summer periods of 2010-2012 years for typical and anomalous (during wild fires) emission rates are presented and compared with satellite TC data (sounders MOPITT, AIRS, IASI). Using simplest dispersion and trajectory models locations of transported main pollution air masses were calculated. This approach allows us to obtain empiric coefficients of correlation between ground-based and satellite CO and CH4 TC data. Correlation with results of ground-based spectrometers was estimated for all three space-borne instruments. The comparison has demonstrated good agreement of satellite and ground-based data in conditions of low atmospheric pollution and systematic underestimation of satellite CO TC (130-200 %) in condition of intense surface emissions. In addition, space-time distribution of forest and peat fires in Central Russia, 2010, was studied by the MODIS data of Aqua and Terra satellites. Uncertainties in fires CO emission estimates were calculated with using of different vegetation maps, assessment techniques and data bases (GFED, GFAS, instruments of SPOT and ENVISAT). The main emission uncertainties in descending order are: the distinctions in emission calculation methods, the differences in vegetation maps, the differences of MODIS data from the satellites Terra and Aqua, and an insufficient registration of forest structure dynamics. In addition we bring the top-down emission estimates obtained by independent method with using of orbital and ground-based spectroscopic measurements of CO total content only.