Variability of fire carbon emissions in equatorial Asia and its nonlinear sensitivity to El Niño

• Published in: Geophysical research letters 2016-10, Vol.43 (19), p.10,472-10,479
• Main Authors: Yin, Yi, Ciais, Philippe, Chevallier, Frederic, Werf, Guido R., Fanin, Thierry, Broquet, Gregoire, Boesch, Hartmut, Cozic, Anne, Hauglustaine, Didier, Szopa, Sophie, Wang, Yilong
• Format: Article
• Language: English
• Subjects: atmospheric inversion; Atmospherics; Bayesian analysis; Carbon; carbon cycle; Carbon emissions; carbon monoxide; Climate; Climate change; Climate models; Combustion; Continental interfaces, environment; El Nino; El Nino phenomena; Emissions; Equatorial regions; Fires; Forest & brush fires; Global warming; Inversions; Land use; Lead time; Meteorology; MOPITT; Ocean temperature; Ocean, Atmosphere; Peat; peat fire; Peatlands; Positive feedback; Probability theory; Satellite observation; Satellites; Sciences of the Universe; Stocks; Tracers; Variability; Water deficit
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2016GL070971

The large peatland carbon stocks in the land use change‐affected areas of equatorial Asia are vulnerable to fire. Combining satellite observations of active fire, burned area, and atmospheric concentrations of combustion tracers with a Bayesian inversion, we estimated the amount and variability of fire carbon emissions in equatorial Asia over the period 1997–2015. Emissions in 2015 were of 0.51 ± 0.17 Pg carbon—less than half of the emissions from the previous 1997 extreme El Niño, explained by a less acute water deficit. Fire severity could be empirically hindcasted from the cumulative water deficit with a lead time of 1 to 2 months. Based on CMIP5 climate projections and an exponential empirical relationship found between fire carbon emissions and water deficit, we infer a total fire carbon loss ranging from 12 to 25 Pg by 2100 which is a significant positive feedback to climate warming. Key Points As constrained by atmospheric inversion, 0.5 +/‐ 0.17 Pg carbon was emitted from the equatorial Asia peat fires in 2015 Fire carbon emissions increase exponentially with cumulative water deficit; possible to forecast it with a lead time of 2 months We infer a future fire carbon loss ranging from 12 to 25 Pg by 2100 in the absence of actions to limit peat burning based on climate projections