B23G-0679
Top-Down Assessment of the Asian Carbon Budget Since the Mid 1990s

Tuesday, 15 December 2015
Poster Hall (Moscone South)
Josep Canadell1, Rona Thompson2, Prabir Kumar Patra3, Frédéric Chevallier4, Shamil S Maksyutov5, Rachel M Law1, T Ziehn1, Ingrid Theodora van der Laan-Luijkx4, Wouter Peters6, A Ganshin3, Ruslan Zhuravlev3, Takashi Maki7, Takashi Nakamura8, Tomoko Shirai5, Misa Ishizawa3, Tazu Saeki3, Benjamin Poulter9 and Philippe Ciais10, (1)CSIRO Ocean and Atmosphere Flagship Canberra, Yarralumla, Australia, (2)Norwegian Institute for Air Research, Kjeller, Norway, (3)JAMSTEC Japan Agency for Marine-Earth Science and Technology, Kanagawa, Japan, (4)LSCE Laboratoire des Sciences du Climat et de l'Environnement, Gif-Sur-Yvette Cedex, France, (5)NIES National Institute of Environmental Studies, Ibaraki, Japan, (6)University of Groningen, Groningen, Netherlands, (7)Meteorological Research Institute, Ibaraki, Japan, (8)Japan Meteorological Agency, Tokyo, Japan, (9)Montana State University, Bozeman, MT, United States, (10)CNRS, Paris Cedex 16, France
Abstract:
Atmospheric carbon dioxide (CO2) is the principle driver of anthropogenic climate change. Asia is an important region for the global carbon budget, with four of the world’s ten largest national emitters of CO2, but it is also a region with considerable uncertainty in both anthropogenic emissions and land biosphere fluxes of CO2. Furthermore, Asia has undergone rapid economic growth over the past two decades, which has been associated with large increases in fossil fuel emissions, 190% for India and 240% for China between 1990 and 2010.

We have used an ensemble of seven atmospheric CO2 inversions and three standard fossil fuel and cement fluxes, based on the inventories of CDIAC, EDGAR and IEA, to determine the land biosphere fluxes for East, South and Southeast Asia, and to ascertain the robustness and overall uncertainty of the results. We find that the East Asian land biosphere was on average a carbon sink of -0.35 ± 0.37 PgC y-1 (median and MAD), or equivalently 17 ± 18% of East Asia’s fossil fuel and cement emissions, over 1996 – 2012. Between 1996 – 2001 and 2008 – 2012, we find an increase in the sink of 0.74 ± 0.28 PgC y-1, however the magnitude of this is contingent on the assumed increase in fossil fuel emissions. For South Asia, we find that on average the land biosphere was close to carbon neutral, -0.01 ± 0.20 PgC y-1 over 1996 – 2012 and that there was no significant trend. For Southeast Asia, we find no evidence for a trend in the land biosphere flux over 1996 – 2012 and we cannot determine any difference from carbon neutrality (as assumed a priori by most inversions) with a flux of 0.06 ± 0.29 PgC y-1, throughout this period despite extensive tropical deforestation.