With the planet still reeling from one of the largest El Niños ever recorded, as heat waves and floods spread around the world, it seems that if you thought things might be over, you’d be mistaken. The effects of the weather phenomenon are looking set to continue well into 2016, with the Amazon rainforest looking particularly at risk.
The research, carried out at NASA’s Goddard Space Flight Center, found that the 2015/2016 El Niño altered the pattern of rainfall over the Amazon, reducing it during the wet season. This has meant that the forest is now drier than it should be at the start of the dry season. In fact, the researchers estimate the forest is the driest it has been going into a dry season since 2002, dramatically increasing the risk of serious forest fires sweeping through the region and destroying large tracts of rainforest.
“When trees have less moisture to draw upon at the beginning of the dry season, they become more vulnerable to fire, and evaporate less water into the atmosphere,” explains Jim Randerson from the University of California, Irvine, who collaborated on building the forecast model. “This puts millions of trees under stress and lowers humidity across the region, allowing fires to grow bigger than they normally would.”
The Amazon fire forecast, a model developed in 2011 to help foresee these events, now predicts that the risk between the months of July and October is greater than seen in both 2005 and 2010, when drought caused wildfires to burn large areas of the rainforest. The team have been working with South American officials and scientists to make them aware of the high risks this year, and have also developed a tool that will allow them to track the evolution of wildfires in real time.
But things may be set to get worse as another, separate, study has found that it looks like human activity is also set to exacerbate this situation. After two years of research, scientists from the Lancaster Environment Centre have found that human disturbances are making the Amazon rainforest more flammable. Even though much of the Brazilian Amazon is protected from widespread deforestation, the researchers found that even through selective logging and forest fragmentation the health of the forest is significantly affected.
Most conservations have praised the large-scale protection of the Brazilian Amazon, where land owners are only allowed to harvest 20 percent of the trees, but even this level of disturbance can reduce the biodiversity level and health of the forest by 50 percent. Punching holes in the canopy can, for example, cause the underlying vegetation to dry up, and thus increase the chance that it could catch fire.