“The region is primed to have record fire activity,” says forecast co-author Douglas Morton, a remote-sensing expert at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. More broadly, a team led by Morton and James Randerson, a biologist at the University of California, Irvine, says that it can predict fire risk across much of the globe—based in part on the influence of the weather pattern El Niño and its counterpart, La Niña.
The El Niño that emerged last year also helped to spawn devastating forest fires in Indonesia, the researchers say. Their work reveals that sea-surface temperatures in the Atlantic and Indian oceans foreshadow fire trends in Central America, Africa and some boreal forests in Earth’s high northern latitudes.
In each case, Morton and Randerson say, ocean conditions can provide a hint of precipitation trends in key forested areas on land several months in advance. “All of these processes are contributing to both the build-up of fuels and the moisture level of those fuels going into the dry season,” Randerson says. “That’s what leads to a predictability in global fire regimes.”
Forecasting vulnerability
Other teams are looking to include fire risk in short-term and seasonal weather forecasts by incorporating independent fire models. These models attempt to account for factors such as vegetation type and the likelihood of lightning strikes or agricultural fires. Eventually, such forecasting systems could integrate more complex phenomenon such as the dynamics of vegetation growth, the way that fire tends to propagate across a landscape and the gases and particles that are emitted during a fire, says Allan Spessa, a fire modeller at the Open University in Milton Keynes, UK.
The European Centre for Medium-Range Weather Forecasts in Reading, UK, plans to soon make public its prototype system to forecast fire risk about six weeks in advance, and the centre’s modellers are working to include fire risk in their seasonal forecasts. Florian Pappenberger, who heads the centre’s work on extreme-weather forecasting, says that the statistical approach used by Morton and Randerson is solid and can serve as an independent check on model forecasts, which come with their own uncertainties. Forecasts for water availability in rivers, reservoirs and agricultural systems operate in such a manner today.
“I don’t think one method replaces the other,” he says. “I expect that merging both will be quite beneficial.”
Ready to burn
“If there were to be a shift in north Atlantic sea-surface temperatures, that could short circuit this fire forecast,” Morton says.
This article is reproduced with permission and was first published on June 29, 2016.
