Days lengthen as spring arrives, but several other signs of the season are showing up earlier and earlier. Some animals and insects aren’t adapting fast enough to this "asynchrony," and there's an increasing disconnect with legal dates that govern hunting and other resource management.

The winter of 2011–12 was the second in a row to feature La Niña, the quasi-cyclic cooling of the eastern tropical Pacific—but the two seasons departed from the La Niña script in strikingly different ways.

A new study finds that extremely warm summers are not only occurring more frequently in the contiguous United States, but are likely to become normal by mid-century.

A new study that provides the first comprehensive satellite analysis of Earth’s melting glaciers and ice caps has grave implications for sea level rise.

The growing array of tools at the disposal of climate scientists doesn’t necessarily make life any easier for them. Each set of data has its idiosyncrasies, some of which aren’t evident at first glance.