A team of scientists is tackling a scenario that is the stuff of Hollywood thrillers: What happens if a medium-sized asteroid strikes Earth? In particular, what if it crashes into the ocean? The question is not fanciful.

Deciduous plants absorb about a third more of a common class of air polluting chemicals than previously realized.

The wildfire that erupted in the foothills west of Boulder in September 2010 sent a thick plume of smoke right over NCAR’s chemistry labs. Even as their offices smelled of smoke, scientists took measurements from the roof.

In 1988, it was the spectre of Yellowstone National Park on fire. In 2003, it was the horror of thousands dying from heat in prosperous western Europe. The planet’s standout heat wave in 2010 plagued much of European Russia, including Moscow.

The difference between El Niño and La Niña can be a huge one for U.S. weather and for global climate. A strong El Niño can nudge global temperatures upward for up to a year.