A map depicts temperature changes over the past 20 years, compared to the average between 1901 and 1960. "The period from 2001 to 2011 was warmer than any previous decade in every region," according to the National Climate Assessment.
Credit NOAA NCDC/CICS-NC
Temperatures will continue to rise in America, "with the next few decades projected to see another 2 degrees [Fahrenheit] to 4 degrees [Fahrenheit] of warming in most areas," according to the latest National Climate Assessment, which came out Friday afternoon.
Opinion polls show 2012's extreme weather — producing wildfires, floods and drought — has more people making a connection with climate change. For Marti Andrews in southern New Jersey, a turning point was the summer's hurricane-like derecho.
"I don't want to say I freaked out about it, but holy crap, it scared me," she says. It packed winds up to 90 miles per hour and nonstop lightning, which Andrews says looked like some wild disco display in the sky.
"I've never seen anything like that," she says. "I sat there on the couch thinking, 'Oh my God, we're all gonna die!' "
Now to a scientist looking back at the year that's about to end, commentator Adam Frank is an astrophysicist. And in the category of science, he is confident about the headline for 2012.
ADAM FRANK: Something remarkable has happened that may etch this year into history for centuries to come. Twenty-twelve's importance comes not through elections, economic shifts or the new movements in art. No, 2012 may well be remembered for something far more elemental.
This was the year that climate change got real for Americans.