Americans remain shaky on the details of climate science even as they have grown increasingly concerned about human activity warming the Earth, according to a national poll by The Washington Post and the Kaiser Family Foundation that probed the public’s understanding of climate change.
The rising alarm is one of the poll's most dramatic findings. In just five years, the percentage of people calling climate change a "crisis" has jumped from 23 percent to 38 percent.
More than 3 in 4 U.S. adults and teenagers alike agree that humans are influencing the climate. The overwhelming majority of them said it’s not too late for society to come up with solutions, but a third of adults who say humans are causing climate change don’t think they can personally make a difference, the poll found.
The poll suggests that many Americans remain early on the learning curve when it comes to knowing what's causing climate change and global warming. For example, 43 percent of adults and 57 percent of teens cited "plastic bottles and bags" as a "major" contributor to climate change, which is incorrect. That response may echo a recent burst of news media attention to plastic pollution in the oceans.
More than a third of Americans, 37 percent, cited "the sun getting hotter" as a major contributor, and another 21 percent called it a minor contributor. Solar activity varies on a regular cycle, but the sun has shown no net increase in radiance since 1950 and is a negligible factor in the observed spike in atmospheric temperature, according to NASA.
Nearly 6 in 10 adults correctly said that driving cars and trucks is a "major" contributor, while about 3 in 10 called it minor and the rest said it's not a contributor or they simply didn't know. In fact, the transportation sector ranks at the top of the major sources of U.S. greenhouse gas emissions, largely as a result of cars and trucks, according to the Environmental Protection Agency.
Twenty-four percent of Americans said airplane travel is a major contributor to climate change, while 44 percent said it's a minor contributor. The EPA finds aircraft contribute about 3 percent of U.S. carbon emissions.
The poll finds 33 percent of adults think that raising cows for food and milk made no contribution to climate change, and only 21 percent said cows are a major contributor. The latter is accurate: A recent report said livestock (including poultry) accounts for 14.5 percent of greenhouse gas emissions, the bulk of that from enteric fermentation - the digestive process that leads cows to belch methane.
Overall, the top sources of greenhouse gases that cause climate change include electricity generation, transportation, agriculture, industrial production and deforestation.
Volcanoes are a source of confusion. About 2 in 10 listed volcanic eruptions as major contributors, and another 4 in 10 called them minor. In fact, volcanic eruptions can cause temporary global cooling when ash and smoke are ejected into the stratosphere and block incoming sunlight - a phenomenon seen, for example, after the eruption of Mount Pinatubo in 1991, which dropped the global temperature by about 1 degree Fahrenheit over the following 15 months, according to NASA.
Several experts on science communication said it's not essential for people to know the precise details about climate change so long as they understand the gravity of the issue, the role of humans and the need to take action.
"I think getting the gist right is the most important thing," said Katharine Hayhoe, a climate scientist who heads the climate center at Texas Tech. "We don't have to understand all the nuances of the science. We just have to understand it's real, it's us, it's serious, and there are solutions."
Kathleen Hall Jamieson, a professor of communication at the University of Pennsylvania, said, "If people have science-consistent attitudes and science-consistent actions, I don't care what their knowledge is. The attitudes will drive policies, the actions will make contributions to fix things."
The sharp increase in the number of people calling climate change a "crisis" has occurred in a time of numerous extreme weather events - such as the devastating hurricanes Harvey, Maria, Florence, Michael and Dorian - as well as an extraordinary run of hot years. This was the hottest decade on record. The five hottest years, according to NASA data going back to 1880, have been, in order, 2016, 2017, 2015, 2018 and 2014.
Jamieson said television meteorologists have been more likely in recent years to cite climate change as a factor in extreme weather events. She noted that the data on global temperature increases are more abstract relative to big storms, floods, droughts, wildfires, and so on. "You're seeing the news media attach the language to things that are evocative and dramatic and have real effects on human lives," she said.
The number of people who completely reject the role of humans in climate has shrunk in recent years, said Ed Maibach, a professor of communication at George Mason University.
"Americans in increasing numbers are coming to understand that climate change is real, that it's human-caused, that there's an overwhelming consensus among the experts that human-caused climate change is happening, that it's bad, that it's harmful to people, not just plants, penguins and polar bears," Maibach said. "And there are things we can do. This is not like a meteor toward Earth - we actually have some options here."
The broad outline of climate change is not scientifically controversial, despite the heavy politicization of the issue in the past two decades. The Earth's atmosphere and oceans have been warming dramatically in the past half-century. Although planetary temperatures do vary on geological time scales, this recent warming is not a natural fluctuation but rather is very likely due entirely to human activity.
The poll showed that 79 percent of adults and 86 percent of teenagers believe that humans are causing the climate to change - a robust majority that still leaves a significant portion of the population rejecting the consensus.
Among those naysayers, 20 percent volunteered that the climate began warming before humans came along, and another 15 percent said humans have no control or play only a small part in the phenomenon. An additional 13 percent said the climate goes through natural shifts and cycles. Another 5 percent attributed the changes to divine will.
The poll suggests that educators, the news media and science communicators have plenty of opportunity to improve public understanding of climate science. Among teenagers, 54 percent say they have learned "a lot" or "a moderate amount" in school about the causes of climate change, while 46 percent have learned about ways to reduce its effects.
"People just don't care, and it's sad. I don't know why. It's just most people don't want to read on it. The reason is because of the way the politics is now. You got so many people arguing about this and that, it's tearing people away from carrying about anything," said Michael D. Young, 46, a Richmond, Indiana, resident and former DirecTV contractor who was surveyed in the poll.
Two-thirds say they disapprove of the way President Donald Trump is handling climate change - a slightly higher rate of disapproval than for any other issue measured in the poll, including health care, immigration, gun policy and the economy.
The answers about the sun getting hotter may reflect, in part, the way the question was worded. Some people may have assumed it referred simply to how it feels when one goes outside on a record-breaking hot day.
"It's very, very hot. That's a problem with the fires in California," Young said.
"We keep seeing all these superstorms, we see it's consistently getting hotter. My son's only one - he's got a long life ahead of him hopefully. I don't want to see him suffer," said Marian Troxler, 38, a parole officer in Madisonville, Louisiana, who participated in the poll.
She acknowledged uncertainty about the cause of climate change. "The way I always understood it, I thought global warming had more to do with the fact that we've broken down so much of our protective layer," she said, referring to the destruction of atmospheric ozone by chlorofluorocarbon gases that have been banned since 1986 under an international treaty.
She said people seeking information will run into echo chambers: "I kind of feel like you can find anything to support your point of view. You can always find something to support what you think and negate what your counterpart might be saying."
Many people are making changes in their lives. The poll found that 53 percent of adults say they've taken actions to reduce their carbon footprints - including about 6 in 10 Democrats and 4 in 10 Republicans. Among those taking action, 38 percent volunteered they are recycling while 37 percent said they are driving less. Roughly a quarter (26 percent) said they are using less electricity in their home, while 17 percent mentioned driving a hybrid or more fuel-efficient vehicle. Only 4 percent volunteered they are eating less meat or none at all.
The Post-KFF survey was conducted online and by telephone from July 9 to Aug. 5, among a national sample of 2,293 adults and 629 teenagers through AmeriSpeak, a survey panel recruited through a random selection of U.S. households by NORC at the University of Chicago. Results among adults have a margin of sampling error of plus or minus three percentage points, and results among teens have an error margin of five points.