Melting Antarctic Permafrost Drove Ancient Global Warming
Fifty-five million years ago, the world abruptly warmed by a scorching 5 degrees Celsius, the oceans turned acidic, and life ran a gantlet of extinction. Sound familiar? That was the closest nature ever came to foreshadowing the fossil-fuel-fed warming that is just getting underway now. But for 15 years, climate scientists have puzzled over how that ancient global warming could have happened. Now a group of researchers is offering a new explanation: The needed greenhouse gases could have gushed from thawing permafrost on an ice-free Antarctica.