Today's Weather Affects People's Beliefs on Global Warming Trends

The public's perception of the weather on a particular day often usurps deeper knowledge by influencing their general opinion on global warming, a new body of research suggests.

Last week, when much of the US was in a deep freeze thanks to a polar vortex that led to freezing temperatures as far south as Florida, many pundits were quick to call foul on the ever-growing body of evidence that global warming is real and that man is influencing it.

On Jan. 6, Donald Trump, an outspoken critic of climate change science, tweeted:

"We are experiencing the coldest weather in more than two decades-most people never remember anything like this. GLOBAL WARMING anyone?"

Numerous other pundits jumped on this bandwagon last week, much to the chagrin of climate scientists and a particularly annoyed Daily Show host Jon Stewart, who lambasted the knee-jerk reaction by climate change deniers in his first episode of the year.

Earlier studies have shown that there is an upward shift in the number of people who agree with manmade global warming when the weather is hot, and a corresponding downward shift when the weather is cold.

But global warming science is based on long-term trends, and a particularly hot or cold day or two is insignificant to the overall global trend. An analogy could be drawn between thinking about global climate change in terms of the weather in a particular area and thinking about the global economy in terms of the amount of money in one person's wallet. When compared to the whole, the individual part is of little consequence.

New research published in the journal Nature Climate Change assesses what goes on in people's minds when they respond to short-term weather trends.

According to the research, which was conducted by scientists with the Earth Institute at Colombia University, "people tend to latch onto the most accessible and immediate information - temperature or otherwise - that they are presented with, and this often trumps deeper knowledge."

To gauge pubic opinion, the researchers administered a number of surveys that collected information on how people perceive climate.

One survey tested for language - like whether on a hot day the term "global warming" had more of an influence on people than "climate change." The answer: Not really.

Another survey revealed that even when given information on the scientific distinction between local temperature and global climate change, people were still prone to use the day's weather as a barometer for their own feelings on climate change.

In another test, the researchers found that the survey respondents' view on climate change was not influenced by yesterday's temperature (a memory) in the same way as today's temperature (an experience) influenced them.

And yet another survey found that a warm day can prompt people to recall more memories of warm days, which led them to overestimate the frequency of unusually warm days.

The research was published as the US was going through some of the coldest weather it has seen in decades.

Lisa Zaval, a graduate student in psychology at Columbia University and lead author of the study, said that the findings could be applied to cold weather events too.

"Our data suggest that perceiving today's local temperature to be colder than usual can lead to decreased belief in and reduced concern about global warming," she said.

A 2011 study, which Zaval was also involved with, assessed people's climate beliefs in relation to the weather found the same to be true.

"Global warming is so complex, it appears some people are ready to be persuaded by whether their own day is warmer or cooler than usual, rather than think about whether the entire world is becoming warmer or cooler," the study's lead author Ye Li said in a statement, "It is striking that society has spent so much money, time and effort educating people about this issue, yet people are still so easily influenced."

Zaval said that a method to combat this effect has yet to be found.