Comparison of SCIAMACHY and AIRS CO_2 measurements over China from 2003 to 2005

摘要

Increased CO_2 (carbon dioxide) has been considered as one of key factors of global warming. Intending to describe the capability of CO_2 measurement by space-borne sensors quantitatively, this paper compares two data sets of CO_2 monthly products retrieved from AIRS and SCIAMACHY over China from 2003 to 2005. The increasing trend of CO_2 concentration can be detected consistently from both of the data sets. However, the seasonal variation of AIRS CO_2 is larger than SCIAMACHY CO_2 because the former represents CO_2 existing in the mid-troposphere while the latter represents in the lower-troposphere. CO_2 concentration reaches its yearly maximum in spring (April and May) and reaches its yearly minimum in late-autumn and winter (October to December and January) for both data sets. The coverage of AIRS monthly CO_2 is much better than that of SCIAMACHY over China and it shows that Xinjiang, Tibet, Inner Mongolia and northeast China have higher values than other regions in China especially in April and May due to local climate and vegetation growth process.