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Many Americans misjudge which personal behaviors have the biggest impact on carbon emissions, researchers have found. But efforts to improve climate literacy that focus too narrowly on individual actions may inadvertently dampen public support for collective solutions.

The findings, published June 9 in , indicate that people tended to overestimate the climate benefits of familiar actions like recycling and switching light bulbs, while underestimating the impact of avoiding one long flight a year or eating less beef.

"People are very misinformed around how their actions can translate into actual impact in terms of reducing carbon," said senior study author Madalina Vlasceanu, an assistant professor of environmental social sciences in the Stanford Doerr School of Sustainability. "We think, 'I have to recycle this and it will help the planet.' It's less likely you will hear that if you fly less, that's the best you can possibly do, lifestyle-wise."

The results are based on a study of nearly 4,000 people in the U.S. recruited to participate in an online survey. Participants in an "active learning" group were asked to rate the relative effectiveness of 21 different individual-level behaviors on a sliding scale and received immediate feedback. "We compared the actions to each other—not tons of carbon. That's something nobody understands. It's so abstract, you'll forget it immediately," Vlasceanu said.

A second group of participants passively received information about the relative mitigation potential of the same behaviors without the prediction step. In the control group, participants received no information. Participants in all groups rated their commitment to the 21 individual behaviors and five additional system-level behaviors, such as voting for pro-climate candidates, as well as the ease of adopting these behaviors.

Unintended consequences

After the interventions, people in both the active learning and passive groups expressed greater commitment to high-impact lifestyle changes like eating lower-carbon meats such as poultry. "Participants found this can be really easy to do, and has one of the highest impacts that has been actually documented," Vlasceanu said. Those who began the exercise with the greatest misperceptions showed the largest shifts in commitments.

But the interventions also produced a worrying side effect. When the content focused solely on personal behaviors, participants became less likely to commit to climate-related collective actions like voting or joining public demonstrations.

"These interventions also decreased commitment to collective action, where you're really trying to influence some sort of policy, and this is a problem," Vlasceanu said.

Personal vs. public action

The findings point to a persistent tension in climate communication efforts: how to encourage effective individual behavior without undermining broader societal engagement. "Now we have to go back and understand how we would better design these interventions so we don't have those negative spillovers," she said.

Although collective actions are harder to quantify in terms of carbon impact, one estimated that a single vote in a recent national election in Canada could be more than 20 times as effective as skipping a long flight—one of the most impactful lifestyle changes scientists have evaluated.

"If you extrapolate from that, you can conclude that all the collective actions are way more effective than all the lifestyle changes you can do, although this still remains to be empirically quantified," Vlasceanu said.

The study also highlighted a difference in what motivates people to act in their personal lives versus in public. "People will engage in lifestyle changes when they think it's easy to do. It's less important to them if it's effective," she said. "For collective action, it is more important to people that the action they engage in will actually result in a meaningful change."

Vlasceanu and co-authors including Danielle Goldwert of New York University collected data in early 2024, with participants averaging 40 years old. Roughly half identified as Democrats, 22% as Republicans, and 26% as independent or other. "Democrats were more sensitive to incorporating what they learned into their behaviors compared to Republicans," Vlasceanu said.

Insights about the human mind

She emphasized that the goal of the research was not advocacy but discovery. "Our job as academics is not to be activists or fight for a particular cause," she said. "These are research questions we scientifically care about that uncover essential processes about the human mind."

The work is part of a broader research program investigating how scalable, low-cost interventions can affect behavior. "We pick the context in which we apply these investigations such that they are societally relevant," Vlasceanu said.

Climate change offers a unique learning opportunity, she said, because it can only be solved through choices and changes involving large numbers of people working together. "If we understand how the mind works in this context, then we can document ways in which practitioners, policymakers—people whose job it is to address this crisis—can most effectively address it," she said.

Future experiments may compare literacy-based strategies with emotional appeals or personal storytelling to determine which approaches most effectively boost both individual and collective engagement.

"In order to meaningfully address climate change, experts have agreed that we will need lifestyle change and collective action. Both of these have to work together," Vlasceanu said. "This is a critical part of the pathway to net zero."