The science is settled.
But 20 percent of Americans still refuse to believe that global warming is occurring, according to a new poll from Yale School of Forestry & Environmental Studies and the Associated Press-NORC Center for Public Affairs Research.
The group surveyed 1,578 adults aged 18 and over. They broke down the results by party affiliation.
We're not even talking here about why global warming — the principal consequence of climate change — is happening, though scientists have stopped debating that too.
We're merely talking about whether it's occurring at all.
Here's a chart from the National Oceanic and Atmospheric Administration (NOAA) showing chart showing the last several hundred millennia of global temperature history.
It's true that scientists have noticed a hiatus in global temperature increases over the past 15 years, a phenomenon they say could last another decade as deep seas continue to absorb a large portion of the heat, but which will flip rapidly once the current cycle ends.
Some experts suggest that most global warming or climate change deniers cannot or will not accept scientific findings because of closely held ideological or religious beliefs.
In any event, to address a threat U.S. Secretary of State John Kerry now says is as grave as terrorism and nuclear proliferation, we'll have to move on without them.
Rob covers business, economics and the environment for Fusion. He previously worked at Business Insider. He grew up in Chicago.