The facts of climate change are widespread. NASA notesfor example, when the global temperature rises by two degrees Celsius, compared to a 1.5 degree C rise, 61 million more people living in urban areas around the world will experience severe drought. Furthermore, the US alone could lose 2.3 percent of its gross domestic product for every degree C increase in global warming.
The problem of communicating these numbers, however, is not faced by many people. Math anxiety—tension, fear, or apprehension when dealing with math problems—and numeracy (an inability to understand and use numerical concepts) are quite common. (For the numerically curious: about a third of working-age Americans struggling with simple numerical processes.)
This reality creates a significant challenge when discussing climate change and other complex issues. If people are worried when they see the numbers, should you use them to provide insight into climate science? Or will this cause people to turn away? In some studies, we set out to answer these questions. Our findings reveal that numbers have the power to persuade, but they must be used with caution to compel action. The lessons we’ve learned can help not only climate advocates, but anyone looking to draw from data to influence their audience.
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We ran it first two studies By the end of 2022 using field data from social networking sites. We’ve collected about eight million posts from climate scientists on Twitter (now X) and over 17,000 posts from the climate change subreddit on Reddit; which is an online community focused on climate change. Our post collection discarded irrelevant text, such as a Twitter handle with numbers. Next, we made a simple classification of the posts by calling them numerically if they included at least one full Arabic. For example, messages with “9” or “27” were numeric. Otherwise, they were classified as unnumbered.
One in four tweets and one in three Reddit posts were numeric. But those messages were shared far more often than numerical tweets and messages. For example, people retweet numeric tweets 16.9 percent more often and Reddit posts 31.7 percent more often. People found these messages and tweets believable enough to want to communicate them to others.
Similarly, numeric posts on Twitter had fewer “likes” on average than non-numeric posts. We believe that providing numerical evidence has shed light on the sheer magnitude of climate threats, making it harder for people to like a tweet (which involves clicking the heart icon) because the message felt worse.
We then ran an experiment to see if the numbers made people think and feel differently about climate science. We recruited 212 participants from an online research platform and presented each with 20 tweets to review, mimicking the experience of scrolling through social media messages. Each participant saw a different message mix. All tweets focused on the effects of climate change (specifically its monetary costs or impacts on the environment and on humans or other species), and each was classified into four categories. Some tweets expressed the effects of climate change in specific Arabic numbers (such as “Every year, Antarctica loses 151 billion tons of ice”). Some presented such findings with vague language related to quantity (“millions of tons of ice”). Others presented their findings without numbers or quantitative language (“lots of ice”). And others had numbers unrelated to climate change outcomes (“lots of ice, according to COP27”).
Ultimately, participants reported that they would be more likely to share and learn more about messages with numerically specific information about the effects of climate change compared to messages in other categories. They also trusted messages more and believed that the sender of the message would be an expert. These effects were stronger among those who were good at math, preferred to receive numerical information, and were more liberal. The numbers had no negative effect on the other participants, however. Those who were more conservative, for example, believed that senders of numerical messages were more knowledgeable than tweeters who did not use specific Arabic numerals to describe climate effects.
Why is mathematical information so compelling even when it makes many people uncomfortable? Despite high count rates, there are reasons to think so that people are not disconnected when they receive the numbers. First, several past studies show that people often you prefer to receive numerical details above mere verbal communication. He also trusts the messages given by people medical professionals or the journalists more so when that communication has numbers than when it doesn’t. Using specific numbers conveys expertise to readers.
But compromises exist. People’s anxiety about math and their level of math ability, there is an upper limit when transmitting this type of detail. In past research, one of us (Peters) found that people find numbers helpful, as long as they aren’t. too many of them. No strict rule is suggested as to how much is too much; it depends on the complexity of the subject, the knowledge people have with the subject and the overall amount. Communicators therefore need to know and attend to their audience: if a speaker sees someone’s eyes glaze over, for example, it’s a sign to back off on the numbers.
In addition to the potential for numbers to overwhelm, their persuasive power can have implications for communicators to consider. Based on our recent findings, for example, we argue that message balance may be particularly important for climate action. Participants in our study reported more negative feelings about tweets with numerical climate change effects. To be clear, we don’t think this reflected math anxiety. Instead, as with the tweets that received fewer likes but were still widely shared, we believe that these tweets generated negative emotions because numerically specific messages were more powerful in conveying the dire consequences of climate change.
Even if people share the numerical facts of climate science more than the non-numerical statements, it may be that they are not disappointed or hopeless. so that they do not take further action. Consider countering that response by talking about viable solutions to the problem. If you suggest actions that people can take forward, maybe counterbalance negative feelings which are created considering the effects of climate change.
So if you’re an environmentalist, want to communicate more effectively through social media, or are looking for strategies to convince families at the Thanksgiving dinner table, here are some lessons. Find key numerical data and share it. Think strategically data presentation. (Numbers and text with visuals they are often helpful when doing risk assessments, for example.) When talking about climate change, include some proposed actions. Since previous work suggests that sharing numbers builds trust, readers or listeners may be more likely to follow your recommendations. Used wisely, numbers can help turn anxiety into action, which can help turn the tide in the fight against climate change.
Are you a scientist specializing in neuroscience, cognitive science or psychology? And have you read any peer reviews recently that you’d like to write for Mind Matters? Please submit suggestions here American scientific‘s Mind Matters editor at Daisy Yuhas dyuhas@sciam.com.
This is an opinion and analysis article, and the views expressed by the author(s) are not necessarily their own. American scientific.
