Americans’ concerns about global warming “are not much different from ‘the record-high levels’ they were at a year ago,” Gallup reported Wednesday.

Yet partisan gaps grew slightly as the issue became even more politically polarized — a point that has garnered a lot of media attention. But that shift appears to be at least partly driven by a drop in the percentage of people self-identifying as Republican.

As Trump chases moderates out of the party, those left are more conservative, more extreme in their views.

For example, 60 percent of all respondents said the effects of global warming have “already begun,” down just slightly from last year’s level of 62 percent (see chart below).

Americans' view on global warming and climate change.

But for Democrats, the percentage who think global warming effects are already evident jumped from 73 percent last year to 82 percent this year. Among Republicans, on the other hand, those who think global warming impacts have begun dropped from 41 percent last year to 34 percent this year. For independents, it also dropped, from 67 percent last year to 60 percent now.


So the issue appears to have gotten much more politically polarized over the last year. But Gallup reported back in December that the percentage of those who self-identify as Republican (or lean Republican) had dropped in the year since Trump’s election.

And, it turns out, that effect was true for this latest poll too. Gallup confirmed by email that the partisan ID for the new climate poll was 23 percent Republican, 45 percent independent. Compare that to the March 2017 climate poll, where the party self-identification was 26 percent Republican, 42 percent independent. (Democratic ID changed only slightly.)

If Trump is chasing moderates out of the GOP, then the remaining pool of Republicans will be more conservative. At the same time, the new pool of independents will likely also be more conservative than it was before, thanks to the influx of former Republicans. And under those circumstances, any survey on an issue like global warming will show an increase in political polarization, when much of it is simply a shift in partisan ID.

That said, it’s obviously still a great concern for U.S. politics that there’s such a great divide. For instance, Gallup found that “while 82 percent of Democrats think global warming has already begun to happen, only 34 percent of Republicans agree.” At the same time, a stunning “57 percent of Republicans think it will not happen in their lifetime (25 percent) or will “never happen” (32 percent).”

With such a chasm, is it possible that the country can come together quickly enough to take the kind of aggressive action needed to avert catastrophic warming? Or are we doomed?

There aren’t any easy answers to those questions. The 2018 and 2020 elections are obviously crucial for preserving a livable climate. But if GOP views on the issue don’t change significantly then whenever they are in power, Republicans will be able to block or reverse the necessary action, as Trump is doing now.