If you’re like the average American, you are probably worried to some degree about climate change. But odds are you don’t spend a lot of time talking about it. At least that’s what the data show.

Social scientists disagree about why this is the case, but a new report from Yale and George Mason University offers a compelling explanation.

The report suggests there is a spiral of silence around climate change. Few Americans, even those who care about the carbon crisis, chat about climate change with friends or family. No one talks, so no one feels comfortable talking. Silence begets silence begets silence, widening the gap between popular discourse and public opinion, in an ever-descending spiral.

How social scientists imagine a spiral. Source: Scheufle & Moy, 2000

The term spiral of silence was coined in 1974 by German researcher Elizabeth Noelle-Neumann, who was attempting to understand the rise of Hitler. She wanted to know how so many people remained silent as the country slipped into the grip of fascism. She found that when everyone is silent, no one speaks up.

Over the years, scholars have applied the theory to a range of issues. Consistently, they find that people don’t speak up for fear of isolation and reprisal. Share an unpopular opinion, and you risk losing friends and social status.

With climate change, there is some evidence of this. Again and again, surveys show that Americans broadly care about the issue, but few talk about it openly. This is apparent in the findings of the Yale/GMU report.

Most Americans care about global warming.

There are several ways to measure concern. The Yale/GMU report looked at who is interested in climate change and who finds the issue personally relevant. Turns out, it’s a lot of people. This is consistent with other other survey data showing that large majorities of Americans believe the climate is changing and think the government should work to cut greenhouse gases.

Few Americans say they hear about global warming in the news.

When asked how often they hear about climate change in the news media, fewer than half of Americans said once a month or more. On this measure, public perceptions are roughly in line with reality. News coverage of climate change is sorely lacking. Last year, broadcast news gave climate change less airtime than Deflategate.

Few Americans talk about global warming with their friends and family.

This is perhaps the most significant factor. The fear of isolation and reprisal is immediate and personal. People look to friends and family to judge which opinions are safe to share. Not many Americans hear their peers talking about global warming, and few are likely to bring it up in conversation — a fact that hasn’t changed much over the past several years.

Here is the smoking gun.

Among people who say they are interested in global warming and say it’s personally important, less than half say they hear about it in the media on a monthly basis. About a quarter say they hear about it from their friends once or more a month. And — here’s where the spiral of silence comes in — less than half talk about it with their peers.

Why is this happening?

Part of the problem is that news coverage hardly measures up to the scale of the problem. It’s a well-established finding in social science that Americans take their cues about which issues are important based on the volume of coverage.

But that doesn’t explain why so few people talk about climate with their family and friends. The rise of social media may be a factor. Political polarization may be as well.

“Our sense is that most Americans don’t raise the issue in conversation because they want to avoid heated or drawn out conversations with people who may hold more extreme views than they do — one way or the other,” said Ed Maibach, professor of communications at George Mason University and lead author of the report.

“It’s a bit like the old adage that it’s impolite to discuss sex, religion, or politics at the dinner table, because it is likely to make someone uncomfortable,” said Maibach. “Our spring 2016 survey found that 56 percent of Americans see global warming as a political issue… that’s more than half the people at any given dinner table.”

But, while climate change has become more polarized, few Americans hold extreme views. Most linger somewhere in the middle — concerned, cautious, disengaged or doubtful, as summed up in previous research from Yale and George Mason University.

Americans cluster into six groups according to their beliefs about climate change. Source: Yale/George Mason Univeristy

“Most Americans are convinced that climate change is happening, but they don’t hold strong feelings about it. Moreover, they mistakenly think that lots of Americans hold strong feelings about it — either alarmed feelings or dismissive feelings,” said Maibach.

Not everyone agrees that what we are seeing is a spiral of silence. David Karpf, professor of communications at George Washington University, offered a competing view.

“I believe the main driver here is that climate change is a quiet crisis. The problem isn’t that it is politicized, or that it isn’t a priority,” said Karpf. “The problem is (1) that there isn’t a set of routinized events that bring it to into public conversation, and (2) we don’t have a clear notion of what we can each do about it.”

“That’s not really a spiral of silence,” he said. “If there were some set of events that acted as a drumbeat and pushed us to either pay attention to climate change or actively ignore it, then I think we’d see a lot more public conversation about climate.”

Compare climate to gun violence, a problem that regularly consumes the news in the wake of mass shootings. These are moments, explained Karpf, “that seize our collective consciousness.” With climate, such flash points routinely go unrecognized. Reporters fail to connect heat waves, droughts and severe storms to global warming, despite a wealth of evidence.

So, while most Americans believe climate change is a problem and worry about it, few are passionate about the issue. What’s needed is more coverage and more conversation about global warming. It’s going to take some work to serve up climate at the dinner table.

Jeremy Deaton writes for Nexus Media, a syndicated newswire covering climate, energy, policy, art and culture. You can follow him at @deaton_jeremy.