The long-lasting effects of El Niño are projected to cause an intense fire season in the Amazon, according to the 2016 seasonal fire forecast from scientists at NASA and the University of California, Irvine. El Niño conditions in 2015 and early 2016 altered rainfall patterns around the world. In the Amazon, El Niño reduced rainfall during the wet season, leaving the region drier at the start of the 2016 dry season than any year since 2002, according to NASA satellite data. 

Wildfire risk for the dry season months of July to October this year now exceeds fire risk in 2005 and 2010, drought years when wildfires burned large areas of Amazon rainforest, said Doug Morton, an Earth scientist at NASA's Goddard Space Flight Center who helped create the fire forecast.

"Severe drought conditions at the start of the dry season set the stage for extreme fire risk in 2016 across the southern Amazon," Morton said.

The Amazon fire forecast uses the relationship between climate and active fire detections from NASA satellites to predict fire season severity during the region's dry season. Developed in 2011 by scientists at University of California, Irvine and NASA's Goddard Space Flight Center, the forecast model is focused particularly on the link between sea surface temperatures and fire activity. Warmer sea surface temperatures in the tropical Pacific (El Niño) and Atlantic oceans shift rainfall away from the Amazon region, increasing the risk of fires during dry season months.

The team also uses data on terrestrial water storage from the joint NASA/German Aerospace Center (DLR) Gravity Recovery and Climate Experiment (GRACE) mission to follow changes in groundwater during the dry season. GRACE measurements serve as a proxy for the dryness of soils and forests.

The NASA and UC-Irvine scientists have worked with South American official and scientists to make them aware of the forecast in recent years. Liana Anderson, a Brazilian scientist from the National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN), said that "fire forecasts three to six months before peak fire activity are important to identify areas with higher fire probability for integrated planning in support of local actions."