A chilly winter and spring have apparently affected the way some Americans think about global climate change, according to a study by the Yale School of Forestry & Environmental Studies.

In a paper called “Climate Change in the American Mind”, researchers report that 63% of all Americans are convinced that global climate change is taking place. But that number is 7 percentage points lower than it was just last fall, probably due to a cold winter and an unusually cold March.

Other findings:

• About half of all Americans (51%) say they are “somewhat” or “very worried” about global warming, a 7 percentage-point decline since last fall.
• Just 16% of those polled do not think the planet is warming up, and 20% say they don’t know.
• Slightly less than half of those polled (49%) think global warming, assuming it is taking place, is caused mainly by human activities, a decline of 5 percentage points since last fall.
• The number of people who think global warming is due “mostly to natural changes in the environment” has increased by 3 percentage points since last fall to 33%.

Misunderstanding the views of scientists

Writing at The Huffington Post, Tom Zeller Jr. said “a far more troubling metric” was that only about 42 of those polled believe that climate scientists are in agreement on the problem.

“A full 33% of respondents are convinced that there remains ‘widespread disagreement’ among scientists on the issue,” Zeller wrote. “This is a problem — both because it is so at odds with reality, and because it likely helps prevent more Americans from recognizing and accepting some pretty straightforward scientific realities.”

Zeller said researchers reviewed abstracts of thousands of scientific articles published in the two decades between 1991 and 2011 and found that less than 3% rejected the idea of climate change caused by humans or were undecided about the connection.

Results of this study were published in May in the journal Environmental Research Letters.

“Scientists are no more divided on the basic mechanics of the greenhouse effect than they are on questions of evolution (sorry folks) or other elementary concepts,” Zeller said.