Science When would global warming destroy life on Earth? Study hazards a guess.

Two new studies look at when a runaway greenhouse effect makes a planet uninhabitable. For Earth, the data suggest that time is still distant, even with current levels of global warming.



A runaway greenhouse effect – where a planet's atmosphere traps so much heat that temperatures rise to life-snuffing levels – may be easier to achieve than previously believed. And there may be more than one way to drive the increase.