LOS ANGELES — For the first time since the United States entered a deep recession five years ago, 70 percent of Americans now say they believe global warming is a reality, according to researchers.
In a report released Thursday by the Yale Project on Climate Change Communication, authors wrote that America’s concern about global warming is now at its highest level since 2008, and that 58 percent of Americans expressed worries about it.
“Historically Americans have viewed climate change as a distant problem — distant in time and distant in space — and perceived that it wasn’t something that involved them,” said environmental scientist and lead author Anthony Leiserowitz. “That gap is beginning to close, however … we’re seeing a jump in the number of people who believe it will affect them or their families.”
American attitudes on climate change shifted remarkably during the recession. While 71 percent of Americans said they believed that global warming was real just prior to the recession in late 2008, the number of believers had plummeted to 57 percent by 2010, according to the study. By the same token, the share of Americans who did not believe in global warming before the recession stood at 10 percent, whereas today its 12 percent.
Many climate scientists said they believed public perception changed dramatically after the start of the recession, in part because economic worries took precedence in people’s minds.
In recent years, however, the number of people who say that global warming is real has grown steadily, according to study authors.
“Additional analysis is required to determine why Americans increasingly believe that global warming is happening, but it is likely due to a number of factors, including the record number of extreme weather events that have occurred over the past two years, including heat waves, widespread drought, floods, wildfires and violent storms. Indeed … more Americans think that the weather in the United States is getting worse.”
Leiserowitz said he expected the trend to continue. While this summer was the third-hottest in the U.S. since record-keeping began in 1895, the entire year is on track to be the nation’s hottest, according to the National Oceanic and Atmospheric Administration.
Those who believe global warming is happening are more certain than those who do not. More than half of Americans who believe global warming is happening (57 percent) say they are “very” (30 percent) or “extremely sure” (27 percent).
For the first time since 2008, more than half of Americans (54 percent) believe global warming is caused mostly by human activities. The proportion of Americans who say it is caused mostly by natural changes in the environment has declined to 30 percent.
A growing number of Americans believe global warming is already harming people both at home and abroad. Four in 10 say people around the world are being harmed right now by climate change, while 36 percent say global warming is currently harming people in the United States.
The study conclusions were based on a survey of 1,061 American adults. The survey was conducted online and took roughly 25 minutes to complete. The sampling was random and respondents who did not have a computer or Internet connection were provided with one.