Comparison analysis of the global carbon dioxide concentration column derived from SCIAMACHY, AIRS, and GOSAT with surface station measurements

Abstract

As a significant greenhouse gas, CO₂ plays an important role in not only the formation of, but also in changes to, the Earth’s climate. A series of remote-sensing detectors have been launched into space to aid the understanding of sources and sinks of CO₂. Although measurements from AIRS (Atmospheric Infrared Sounder), SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Cartography), and GOSAT (Greenhouse Gases Observing Satellite) have been frequently used to retrieve atmospheric CO₂ concentrations, there are no comprehensive comparison analyses between satellite data and ground data. In this article, the characteristics of the current common observing platforms and their product data are compared and analysed. Correlation coefficient, RMSD, and bias are used to evaluate the CO₂ retrieved from satellite data. The results reveal that: SCIAMACHY has limitations in detecting CO₂ over the ocean; GOSAT has the poorest coverage on a global scale but has a better capability to detect CO₂ over the sea than SCIAMACHY; and AIRS can reflect the distribution and changes of CO₂ very well. The differences in coverage and accuracy indicate the necessity to produce consistent products with improved spatial and temporal features and indicate a future development trend for instruments including higher spectral resolution, higher spatial resolution, wider coverage, shorter revisit periods, and higher signal to noise ratios.

Additional information

Funding

Funding support was provided partially by the NSF China Major Programme [41171324], The Funds for PhD Education [20110091110028], and The Fundamental Research Project of MOST [2005DKA32306].