Prepare for a drier, more flammable Amazon

“Prepare for El Niño,” the World Meteorological Organization (WMO) said in a statement in early May. Climate authorities, such as the U.S. National Weather Service, believe there is a 90 percent chance of the phenomenon hitting the globe in a moderate to intense manner in the second half of the year, after three years of La Niña.

“The development of an El Niño will most likely lead to a new spike in global heating and increase the chance of breaking temperature records,” said WMO Secretary-General Petteri Taalas. 

For the Amazon rainforest, this forecast is especially worrying. “The forest can become a tinderbox ready to catch fire,” warns Erika Berenguer, a researcher at the universities of Oxford and Lancaster specializing in Amazon fires.

El Niño is the warming phase of the waters in the eastern Pacific, off the coast of South America. It disrupts weather and temperature around the globe, unpredictably creating heat waves, floods, or droughts in different regions. In 2015, for example, the phenomenon doubled the period of rain scarcity in the Amazon region, from four to eight months. “We even saw areas of the floodplain on fire,” says the scientist.

She conducted research that shows that the El Niño drought killed more than 2.5 billion plants in an area representing just 1.2 percent of the Amazon between 2015 and 2016. That alone released more greenhouse gasses into the atmosphere than an entire year of deforestation across the whole rainforest.

A majority of the Amazon — 69 percent of its total surface area — is prone to drought and risks being affected by uncontrolled fires, according to the calculations of researcher Celso Silva-Junior. “These are areas that,...