Tag Archives: Climate Change

The World’s Second-Largest Rainforest Is Losing the Carbon It’s Held for a Thousand Years

The Congo Basin is the second-largest rainforest on Earth, and like most tropical forests, it’s getting chewed up by humans. That’s a problem for the climate, and not just because trees are a natural sponge helping to mop up humanity’s ever-rising carbon emissions. New research suggests that as trees are replaced with fields for agriculture, carbon that’s been locked up in the Congo’s soils for hundreds to thousands of years is starting to seep out. Continue reading The World’s Second-Largest Rainforest Is Losing the Carbon It’s Held for a Thousand Years

How Does Earth’s Carbon Cycle Work?

Hundreds of millions of years ago, massive ice caps sheathed Earth’s continents from coast to coast. Only the peaks of the planet’s mountains stood above the ice as glaciers ground and crushed their way through the bedrock, meandering slowly toward the snow-covered plains. Where the glaciers met the oceans, huge blocks of ice and rock calved from the glaciers and dropped into the sea. Life, mostly algae, cyanobacteria and other bacteria, somehow persisted in the small ice-free pockets of ocean water. Like an icy planet in a distant solar system, Earth during its formative years, a juvenile phase known as the “Snowball” Earth, was a far different place than the mostly blue planet of today. Continue reading How Does Earth’s Carbon Cycle Work?

Record-Breaking Heat in Alaska Wreaks Havoc on Communities and Ecosystems

Alaska in March is supposed to be cold. Along the north and west coasts, the ocean should be frozen farther than the eye can see. In the state’s interior, rivers should be locked in ice so thick that they double as roads for snowmobiles and trucks. And where I live, near Anchorage in south-central Alaska, the snowpack should be deep enough to support skiing for weeks to come. But this year, a record-breaking heatwave upended norms and had us basking in comfortable—but often unsettling—warmth. Continue reading Record-Breaking Heat in Alaska Wreaks Havoc on Communities and Ecosystems

This Simulation Maps the Rise and Fall of Species Over 800,000 Years

The Amazon and the adjacent Andean slopes in South America host an astonishing richness of plants and animals. These species have been sources of food, shelter and medicine since the arrival of humans and a target of scientific curiosity since the days of the earliest European naturalist explorers.

Continue reading This Simulation Maps the Rise and Fall of Species Over 800,000 Years

Rare 85,000-year-old Finger Bone Complicates Our Understanding of African Migration

For years, archaeologist Huw Groucutt and his team had driven one particular stretch of desert on their way to dig sites in Saudi Arabia. As they drove they caught glimpses of what looked like bones, emerging from the slowly eroding sand. Finally, in 2014, the team decided to explore the array of bones at Al Wusta. Within two years, amidst more than 800 fossilized animal bones and nearly 400 stone artifacts, they discovered something remarkable: the middle digit of a finger bone, from what appeared to be a modern human. Continue reading Rare 85,000-year-old Finger Bone Complicates Our Understanding of African Migration