Only a third of Republican voters blame humans as main cause of climate change

Despite largely contrasting opinions between supporters of the two major US political parties, scientists also find Republican views on climate change are ‘more varied than might be presumed from political discourse'

Republicans are far less likely than Democrats to believe in climate change, scientists say (Alex Wong/Getty Images)

An ambitious new study has demonstrated the stark differences of opinion about climate change that exist between supporters of the two major US political parties.

The findings also reveal considerable nuance, with many Republicans apparently holding views that contradict those of their party leaders.

Combining state voter files with opinions on climate and energy collected over an eight-year period, a team led by Professor Matto Mildenberger of the University of California, Santa Barbara, was able to estimate the distribution of Republican and Democratic opinions across the US.

The researchers used this information to create an interactive map that reveals opinions at a national, state and congressional district level. They published their results in the journal Climatic Change.

Map showing proportions of Republicans who place the blame for global warming primarily on humans, with darker regions less likely to agree that humans are to blame (Matto Mildenberger, Jennifer Marlon, Peter Howe, Xinran Wang and Anthony Leiserowitz)

Taking a national average, the data reveal that 82 per cent of Democrats believe global warming is happening, compared to only 50 per cent of Republicans.

Similarly, there was a partisan split when it came to taking responsibility for climate change, with 66 per cent of Democrats saying global warming is caused mostly by humans, and only 31 per cent of Republicans agreeing.

Republican opposition to climate science is well established.

Recent stories on this theme include a Republican Congressman claiming that if climate change exists “God can take care of it”, and Republican islanders refusing to acknowledge the rising sea levels swallowing their homes.

Such attitudes have been cemented by President Donald Trump, who has famously described climate change as “a hoax” and withdrawn his nation from the Paris Agreement on climate change.

“Arguably the Republican party in the US is the most important political actor globally organised against climate reforms,” said Professor Mildenberger.

Map showing proportions of Democrats who place the blame for global warming primarily on humans, with darker regions more likely to agree that humans are to blame

However, besides revealing the disparity between Democrats and Republicans surrounding climate issues, this new study also reveals substantial variation in opinions across states and congressional districts.

This is particularly true of Republicans.

“While subsets of the Republican voting public do not support climate policies and hold views consistent with party elite, Republican climate and energy opinions are more varied than might be presumed from political discourse,” said Professor Mildenberger.

Predictably perhaps, higher proportions of Republicans on the east and west coasts accept that global warming is happening. However, there were more surprising results as well.

“Florida Republicans tended to have stronger climate beliefs than the national average,” said Professor Mildenberger.

“That’s a place that isn’t viewed as being a liberal hotbed but nonetheless has quite strong climate beliefs among Republicans.”

Regional variation in climate change opinion has proved crucial since the Trump administration’s withdrawal from the Paris Agreement, as local politicians have had to take over the reins of climate action.

In California, where belief in climate change is among the highest for both Democrats and Republicans, Governor Jerry Brown has vowed to host his own climate change conference, declaring that Donald Trump “doesn’t speak for the rest of America”.