Quiz: What’s the Best Way to Shrink Your Carbon Footprint?

Blue flowers growing out of a field of gray smog.
Cristina Daura

By Sander van der Linden

Sander van der Linden is a professor of psychology at the University of Cambridge. He previously served as editor in chief of the Journal of Environmental Psychology.

This fall, climate activists captured the public’s attention after they threw soup at one of Van Gogh’s sunflowers paintings and glued themselves to Johannes Vermeer’s ‘‘Girl With a Pearl Earring.” While the activists’ stunts prompted a debate about the effectiveness of radical tactics for systemic change, the spectacles may have left some wondering just what exactly they should be doing at home.

Lists of ways to reduce your personal greenhouse gas emissions are plentiful online, with recommendations ranging from using energy-saving light bulbs to not having children. The number of options can feel overwhelming, and there’s another problem: Researchers have found that people often adopt habits that may seem significant but actually have a very small effect on limiting climate change.

I’ve been studying how people think and feel about climate change for over a decade. During that time, I’ve found that while the public’s understanding that climate change is happening has increased, practical knowledge about what we can do to counter it is lacking. To demonstrate how far we have to go, I worked with Times Opinion and Ipsos to test about 1,000 Americans’ ability to size up various ways to reduce greenhouse gas emissions. Take the quiz below to see how you stack up.

What’s the best way to reduce emissions?

Guess whether each action below would have a small, moderate or large effect on reducing personal greenhouse gas emissions.

Effect Share of Americans who got it right
Small Moderate Large
Buying fewer things
Lowering the room temperature
Installing heat pumps
Using energy-efficient appliances
Car-pooling
Recycling
Eating a vegetarian diet
Living car-free
Eating organic food
Using renewable electricity
Avoiding a long flight
Eating a vegan diet
Sources: Survey by Ipsos; small, moderate and large effect categorizations by Times Opinion, based on estimates from “Quantifying the potential for climate change mitigation of consumption options” by Diana Ivanova, John Barrett, Dominik Wiedenhofer, Biljana Macura, Max Callaghan and Felix Creutzig Note: Responses were weighted to be nationally representative. Results for Americans who correctly guessed “small effect” also include those who thought the action might have no effect.

If you got a few of the answers wrong, you’re in good company. The Times Opinion/Ipsos survey found that Americans tend to underestimate the effects of actions that are harder to take, like avoiding air travel or adopting a vegan diet. And they overestimate the amount of emissions avoided by using energy-efficient appliances and recycling.

Looking at the survey results, it appears that many Americans conflate the primary benefit of recycling — less pollution and waste — with the potential to meaningfully address a very different problem: climate change. Researchers have observed this phenomenon in the past, finding that Americans tend to mix up environmental problems like pollution, the hole in the ozone layer and the greenhouse effect.

The moral halo around recycling is largely a result of a decades-long disinformation campaign by plastic manufacturers. Since the 1980s, the fossil fuel industry has spent millions of dollars on advertisements telling people to recycle, despite the fact that a large majority of plastic products can’t be salvaged and end up in landfills. In April, the California attorney general announced an investigation into the fossil fuel and petrochemical industries’ “aggressive campaign” to promote recycling and “deceive the public.”

The success of the disinformation campaign around recycling can largely be chalked up to a phenomenon that psychologists call the “illusory truth” effect. It happens when people mistakenly think a claim is more likely to be true just because it has been repeated. And the virtues of recycling have been repeated many times. For example, a 2017 study of Canadian textbooks found that recycling was the most commonly recommended way to mitigate climate change. Only 4 percent of the textbooks’ recommendations focused on high-impact behaviors such as avoiding air travel.

So where does that leave us? Although estimating the carbon footprint of specific actions is not an exact science, we can raise awareness about actions that most researchers agree are necessary to slow climate change.

Specifically, we need to fight influential misperceptions. Recycling is one example; so is misinformation around electric vehicles. Many Americans believe that electric cars are more expensive to maintain than gas-fueled cars. In fact, electric cars are often cheaper to own over their lifetimes. And tax credits in the recently signed Inflation Reduction Act should significantly reduce the cost of buying an electric vehicle. These facts are worth bringing up around the dinner table because preemptively refuting misinformation is one of the most effective ways to counter its spread.

While governments and businesses have the most power to reverse climate change, perhaps the best thing we can do as individuals is to hold them accountable, dispel influential myths and shift our collective attention to the actions that matter most. Although the jury is still out on the effectiveness of throwing soup at famous artworks, we know that switching to clean energy, flying less and adopting a plant-based diet are some of the most effective ways to help save our planet.