NOAA scientists have documented a new impact of the increasingly thin blanket of Arctic sea ice: gases escaping from the thinner ice in spring are affecting air chemistry, reducing ground-level ozone, and likely increasing mercury contamination.

NOAA's Climate Scene Investigators analyzed why the mid-Atlantic region had record-setting snowstorms this winter. The team looked for but found no human "fingerprints" on the severe weather. Instead, they fingered two naturally occurring climate patterns as co-conspirators in the case.

NOAA researchers have built a "time machine" for weather that provides detailed snapshots of the global atmosphere from 1891 to 2008. The system's ability to "hindcast" past weather events is emerging as a powerful new tool for detecting and quantifying climate change.

Flooding in Cedar Rapids, Iowa

In NOAA's version of CSI, Marty Hoerling leads a group of climate and weather researchers who investigate killer climate patterns—heat waves, tornadoes, and floods—to figure out what may have triggered them.