The seasonal variation of the CO₂ flux over Tropical Asia estimated from GOSAT, CONTRAIL and IASI

Sourish Basu (1, 2, 3) , M. Krol (2, 3, 4) , A. Butz (5) , Cathy Clerbaux (6) , Y. Sawa (7) , T. Machida (8) , H. Matsueda (7) , C. Frankenberg (9) , O. P. Hasekamp (3) , I. Aben (3)

1 ESRL - NOAA Earth System Research Laboratory
2 IMAU - Institute for Marine and Atmospheric Research [Utrecht]
3 SRON - SRON Netherlands Institute for Space Research
4 MAQ - Meteorology and Air Quality Department [Wageningen]
5 IMK - Institute for Meteorology and Climate Research
6 TROPO - LATMOS
7 MRI - Meteorological Research Institute [Tsukuba]
8 NIES - National Institute for Environmental Studies
9 JPL - Jet Propulsion Laboratory

We estimate the CO₂ flux over Tropical Asia in 2009, 2010 and 2011 using GOSAT total column CO₂ (XCO₂) and in situ measurements of CO₂. Compared to flux estimates from assimilating surface measurements of CO₂, GOSAT XCO₂ estimates a more dynamic seasonal cycle and a large source in March - May 2010. The more dynamic seasonal cycle is consistent with earlier work by Patra et al. [2011], and the enhanced 2010 source is supported by independent upper air CO₂ measurements from the CONTRAIL project. Using IASI measurements of total column CO (XCO), we show that biomass burning CO₂ can explain neither the dynamic seasonal cycle nor the 2010 source. We conclude that both features must come from the terrestrial biosphere. In particular the 2010 source points to biosphere response to above-average temperatures that year.

Mots clés: GOSAT; inverse modeling; Tropical Asia; CONTRAIL; IASI

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]; Sciences de l'environnement

Sourish Basu, M. Krol, A. Butz, Cathy Clerbaux, Y. Sawa, et al.. The seasonal variation of the CO₂ flux over Tropical Asia estimated from GOSAT, CONTRAIL and IASI. Geophysical Research Letters, 2014, 41 (5), pp.1809-1815. ⟨10.1002/2013GL059105⟩. ⟨hal-00951800⟩