Winter in Anchorage, Alaska, is defined by snow, but as the climate warms, recent winters have seen more ice. It's a trend that's led to safety concerns and new measures to cope.
The Fraser fir is found in a lot of homes around Christmas. But its wild cousins have been in decline for almost a century because of a small invasive pest.
Investigators say they believe the substance found on a freeway north of Detroit is groundwater mixed with a chemical called hexavalent chromium. The public safety risk is minimal, officials say.
NPR's Michel Martin speaks with climate scientist Brenda Ekwurzel about how the climate has changed over the last decade and what that means for the next one.