Wildfire seasons have gotten almost 20 percent longer

Climate change is setting the world on fire. Between 1979 and 2013, the duration of wildfire seasons increased across 25.3 percent of Earth’s vegetated surface, with net gains on every continent except Australia and Antarctica, researchers report online July 14 in Nature Communications.

Wildfire seasons encompass hot, dry times of year when vegetation readily burns. Only about one-tenth of vegetated areas saw decreases in fire season length during that same time span, the researchers report.

This incendiary increase comes primarily from climate change effects such as rising global temperatures and worsening droughts, the researchers say. And more wildfires could make climate change even worse by releasing extra carbon dioxide into the atmosphere. In 1997, Indonesian wildfires released the carbon equivalent of 13 to 40 percent of the world’s average annual fossil fuel emissions, the researchers note.