Reduced carbon uptake during the 2010 Northern Hemisphere summer as observed by GOSAT
Guerlet, Sandrine1; Basu, Sourish2; Butz, Andre3; Krol, Maarten4; Hahne, Philip3; Sander, Houweling2; Otto, Hasekamp5; Aben, Ilse5
1SRON, LMD-IPSL, FRANCE; 2SRON, IMAU, NETHERLANDS; 3KIT, GERMANY; 4WUR, IMAU, SRON, NETHERLANDS; 5SRON, NETHERLANDS
Improved knowledge of land-atmosphere carbon dioxide (CO2) fluxes, their variability and their response to climate events such as drought, flood and heat waves is needed to better understand the carbon cycle and its response to climate change. Until recently, constraints on large scale CO2 fluxes were derived from observed gradients of near surface dry air CO2 mole fractions. However, many regions remain heavily under sampled by the current in-situ near-surface CO2 measurement networks. The Greenhouse Gases Observing Satellite (GOSAT) was launched in January 2009 with the goal of measuring CO2 on a global scale to improve on this situation. It is the first satellite mission dedicated to the measurements of the greenhouse gases CO2 and CH4. By now we have analised a few years of GOSAT data which reveal significant inter annual variation of CO2 uptake during the Northern Hemisphere summer between the years 2009 and 2010. The reduced carbon uptake that we observe with GOSAT in the summer of 2010 is likely related to the heat wave in Eurasia driving biospheric fluxes and fire emissions. This study is a nice illustration of the added value of satellite observations for studying the carbon cycle.