Journal Article

Simulated resilience of tropical rainforests to CO2-induced climate change

Sitch, Stephen, Kay, Gillian, Betts, Richard, Harris, Phil P., Galbraith, David, Booth, Ben B. B., Malhi, Yadvinder, Cox, Peter M., Huntingford, Chris, Good, Peter, Zelazowski, Przemyslaw, Meir, Patrick, Lewis, Simon L., Lloyd, Jon, Mercado, Lina M., Jones, Chris D., Marengo, Jose, Lomas, Mark, Gloor, Emanuel, Nobre, Carlos, Atkin, Owen K., Fisher, Rosie, Phillips, Oliver L., Zaragoza-Castells, Joana, Walker, Anthony P., Hemming, Debbie

2013

Overview

Assessing potential future carbon loss from tropical forests is important for evaluating the efficacy of programmes for reducing emissions from deforestation and degradation (REDD). An exploration of results from 22 climate models in conjunction with a land surface scheme suggests that in the Americas, Africa and Asia, the resilience of tropical forests to climate change is higher than expected, although uncertainties are large. How tropical forest carbon stocks might alter in response to changes in climate and atmospheric composition is uncertain. However, assessing potential future carbon loss from tropical forests is important for evaluating the efficacy of programmes for reducing emissions from deforestation and degradation. Uncertainties are associated with different carbon stock responses in models with different representations of vegetation processes on the one hand 1 , 2 , 3 , and differences in projected changes in temperature and precipitation patterns on the other hand 4 , 5 . Here we present a systematic exploration of these sources of uncertainty, along with uncertainty arising from different emissions scenarios for all three main tropical forest regions: the Americas (that is, Amazonia and Central America), Africa and Asia. Using simulations with 22 climate models and the MOSES–TRIFFID land surface scheme, we find that only in one 5 of the simulations are tropical forests projected to lose biomass by the end of the twenty-first century—and then only for the Americas. When comparing with alternative models of plant physiological processes 1 , 2 , we find that the largest uncertainties are associated with plant physiological responses, and then with future emissions scenarios. Uncertainties from differences in the climate projections are significantly smaller. Despite the considerable uncertainties, we conclude that there is evidence of forest resilience for all three regions.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 704/106/35 / 704/158/2454 / 704/158/47 / Carbon dioxide / Climate change / Climate models / Deforestation / Earth Sciences / Earth System Sciences / Emissions control / Geochemistry / Geology / Geophysics/Geodesy / letter / Physiological responses / Physiology / Rainforests / Tropical forests