Fire decline in dry tropical ecosystems enhances decadal land carbon sink

The current synthesis of process-based estimates of land and ocean sinks requires an additional sink of 0.6PgC yr(-1) in the last decade to explain the observed airborne fraction. A concurrent global fire decline was observed in association with tropical agriculture expansion and landscape fragmentation.

Here we show that a decline of 0.20.1PgC yr(-1) in fire emissions during 2008-2014 relative to 2001-2007 also induced an additional carbon sink enhancement of 0.4 +/- 0.2PgC yr(-1) attributable to carbon cycle feedbacks, amounting to a combined sink increase comparable to the 0.6PgC yr(-1) budget imbalance. Our results suggest that the indirect effects of fire, in addition to the direct emissions, is an overlooked mechanism for explaining decadal-scale changes in the land carbon sink and highlight the importance of fire management in climate mitigation. p id=Par In recent history the amount of carbon captured by terrestrial systems has increased, but the processes driving this process has remained poorly constrained.