Brazil's natural areas shrink, worsening El Nino impact

Brazil has lost an area of native vegetation more than twice the size of France in the past four decades, increasing vulnerability to extreme weather events from El Nino, a study showed on Wednesday.

Different areas of the vast nation are bracing for droughts, floods and fires as the El Nino weather pattern, confirmed in June, is expected to intensify towards the end of the year.

In its annual study of land use in Brazil, environmental monitoring network MapBiomas said that native vegetation, which covered 79 percent of Brazil's territory four decades ago, now covers only 65 percent.

The biggest losses were seen in the Amazon rainforest and biodiverse Cerrado savanna.

Much of the affected land was converted for agriculture or livestock farming, which now covers 32 percent of Brazil's territory, up from 18 percent in 1985.

An analysis by MapBiomas showed that areas where native vegetation had given way to agriculture were more vulnerable to weather extremes during El Nino events that were as strong as this year's is forecast to be.

Tasso Azevedo, general coordinator of MapBiomas, told AFP that deforested areas of the Amazon had experienced "a more significant drop in rainfall compared to forested areas" during the 2023-2024 El Nino.

Meanwhile, in agricultural areas of the southern grasslands, there was excess rainfall compared to areas of native vegetation.

The southern state of Rio Grande do Sul suffered historic floods in 2024 which left around 200 people dead.

"Land-use patterns don't change El Nino itself, but they can alter the impact it has," said Azevedo.

"This shows that our land-use decisions can impact our level of vulnerability and determine how intense these climate events will be in the country."

He said the study did not address why agricultural areas experienced more intense impacts from El Nino.

"But one hypothesis is that, in the Amazon, removing forest reduces evapotranspiration and local air humidity. This leads to rising temperatures and reduced rainfall... El Nino amplifies the magnitude of the effect."

Last month, Brazil's government warned of a "very strong El Nino" this year, with Pacific Ocean sea-surface temperatures forecast to exceed two degrees above average temperatures.

This warming can have major effects on weather patterns around the world.

The Brazilian Confederation of Agriculture and Livestock (CNA) has also warned that a "super El Nino" could impact crops such as coffee, soy and sugar.