Glob. Biogeochem. Cycles http://doi.org/jgs (2012)

Credit: © ISTOCKPHOTO/THINKSTOCK

Climate is an important control on the frequency and extent of biomass burning globally, but fire risk sensitivity to changes in climatic factors like temperature and moisture balance remains unquantified. Fires can influence climate through the release of trace gasses and aerosol precursors, as well as carbon dioxide, so a better appreciation of feedbacks between climate and fire risk could improve climate change modelling.

Anne-Laure Daniau from the School of Geographical Sciences, University of Bristol, UK and co-workers analyzed sedimentary charcoal records to investigate changes in fire regime over the past 21,000 years and its relationships with regional climates.

Results show that fire risk increases predictably with changes in temperature, peaking at intermediate moisture levels. The authors note that temperature is quantitatively the most important driver of changes in biomass burning over the last 21,000 years, indicating a positive climate change feedback in the face of continuing global warming.