Brazil’s Atlantic Forest will change more in next 50 years than any time since last ice age

Brazil’s Atlantic Forest is one of the most biologically diverse places on Earth. Roughly one in every 50 plant and land-dwelling vertebrate species is endemic to the region and is found nowhere else in the world.

Stretching for 3,000 kilometers along much of Brazil’s coast and spreading inland as far as Argentina and Paraguay, the incredible biodiversity of the Atlantic Forest comes from its mosaic of different ecosystems, including natural grasslands, tropical rainforests, ancient forests adapted to wintry chills, misty mountainous “cloud forests,” and more.

But its eye-watering richness of life is in grave danger: the Atlantic Forest has been shattered by several centuries of deforestation and changing habitats. Now, the upheaval we are causing to Earth’s climate systems threatens, within decades, to bring greater disruption to the Atlantic Forest’s ecosystems than any natural changes have for many thousands of years.

Even today, only fragments of the Atlantic Forest remain. Just one-quarter of the existing forest is more than 250 meters — a three-minute walk — from open land. Well over 80 percent of its natural vegetation has been destroyed since European colonizers arrived in Brazil; some Atlantic Forest ecosystems have a 50-percent chance of collapsing within the next 50 years.

Global warming poses another immediate threat. While the Earth’s climate has always undergone changes, disruptions this century are likely to be faster and more pronounced than anything humankind has seen before. Higher temperatures and more variable rainfall will be a particular challenge in the south of the Atlantic Forest, where ecosystems comprise a...