Credit: © ISTOCKPHOTO / CHIEH CHENG

Global wildfires may become more prevalent throughout the twenty-first century, and increasingly driven by climate rather than by human activity.

Olga Pechony at Columbia University and Drew Shindell from the NASA Goddard Institute of Space Studies, both in New York, modelled global fire trends from 844 to 2003 and projected these trends out to 21001. Using climate modelling, land cover and population data, they looked at major drivers of global fires over time. Whereas fire trends were largely driven by precipitation in pre-industrial times, human activities such as fire ignition and suppression became the dominant driver in the nineteenth century. In the future, temperature is likely to take over from direct human activity as the root cause of global wildfires.

The authors caution that although their modelled results compare reasonably well with historic fire trends reconstructed from charcoal records, information on fire-related human activities is highly incomplete. The future of fire activity is still uncertain, they say, and note that advances in fire suppression could reduce the increase in fires significantly.