Asian contribution

Nature Commun. http://doi.org/bc6t (2016)

In the past two decades Asia has become one of the largest emitters of CO₂ globally, due to increased fossil fuel emissions tied to rapid economic growth. Extensive land-use changes in this region have also contributed to changes in the carbon budget, but the magnitude and sign of this contribution are still uncertain.

Rona L. Thompson, from the Norwegian Institute for Air Research, and colleagues used atmospheric inversion models — which combine CO₂ observations with atmospheric transport simulations — to estimate the trend in land biosphere CO₂ fluxes in Asia from 1996 to 2012.

They find the Asian land biosphere was a net CO₂ sink for this period (−0.46 PgC per year), driven by the increasing sink in East Asia, while South and Southeast Asia remained carbon neutral. The increase in the East Asia sink represents 35% of the increase in the global land sink for the same period. However, large uncertainties in China's fossil fuel emissions result in large uncertainties in the estimation of changes in the land-sink.

The large contribution of land-use changes in Asia to the land CO₂ sink highlights the need to account for these in land surface models for better estimation of the carbon budget.