Earth Scientists Pin Climate Change Squarely On ‘Humanity’

Most of the scientists who study the Earth say our climate is changing and humans are part of what’s making that happen. But to a lot of nonscientists it’s still murky. This week, two of the nation’s most venerable scientific institutions tried to explain it better.

The federal government’s National Oceanic and Atmospheric Administration issued its annual State of the Climate report Tuesday. Mostly, it was bad news: rising sea levels, less sea ice in the Arctic and warmer oceans. NOAA said 2012 was in the top 10 hottest years on record for global average temperature, but in the U.S. it was the hottest on record.