When the ‘new normal’ becomes too normal

Source: Chelsea Harvey, E&E News reporter • Posted: Wednesday, February 27, 2019

From increasing severe weather events to extreme temperatures, scientists often suggest that global warming is defining a “new normal” for climate conditions around the world. And the public may be getting a little too used to it.

A new analysis published yesterday in Proceedings of the National Academy of Sciences suggests that when unusual or extreme weather conditions start to happen more frequently, they become less remarkable. In other words, they start to feel normal.

The researchers raise the possibility that this normalization could affect the public’s perception of climate change. If climate extremes start to seem less unusual, then the need for climate action may start to seem less urgent.

“The goal of [this work] is to try and bridge the gap between people’s everyday experiences of the weather, and this longer-term kind of century-scale perspective that we think about, when we think about, ‘Is this evidence of climate change or not?'” said lead author Frances Moore, an environmental scientist at the University of California, Davis.

To judge the public’s feelings about the weather, Moore and colleagues took to social media. They compiled more than 2 billion tweets posted by U.S. users between 2014 and 2016 and scanned them all to find the ones that were discussing the weather. They also assembled temperature and precipitation data from the same period.

The analysis found that people were more likely to tweet about the weather during short periods of unusual cold or heat — no real surprise there. But they also found that when unusually high or low temperatures cropped up repeatedly year after year, people started to lose interest in them. After about five years, the temperatures would become unremarkable.

The researchers wondered if this might be because people were finding ways to adapt to new temperature extremes — maybe people weren’t tweeting about them because they weren’t physically bothered by them anymore.

But a closer look at the Twitter data suggested this probably wasn’t the case. When people did tweet about the weather, they still talked about it in negative ways. The researchers suggest that people simply become less inclined to comment on the weather when they get to a point where it’s no longer unexpected — even if the temperatures themselves are still physically uncomfortable or even dangerous.

The research raises some important questions about how “normalization” of severe climate conditions might affect public views on climate change.

“There is kind of a fairly large literature out there that shows that if you call people up and you ask them, ‘Do you believe in climate change,’ they’re more likely to say yes if it’s unusually hot outside,” Moore pointed out.

This kind of research might suggest that as hot extremes become more common, more and more people should begin to embrace the existence of climate change.

“But what this [study] suggests is that that phenomenon won’t necessarily lead to everyone believing in climate change just because it’s getting hotter,” Moore added.

Still, other scientists point out that interest in climate change seems to be on the rise.

“It’s not just belief in climate change, but even concern about climate change and even support for action,” said John Cook, an expert in cognitive science at the Center for Climate Change Communication at George Mason University, who’s been collecting survey data on climate change for about a decade. “We find that on all those variables it’s been increasing over the last 10 years, and especially in the last several years.”

The authors of the new study note that there are other climate-related events that may be more difficult for people to normalize, in part because their consequences tend to be more dramatic — hurricanes, wildfires, major droughts and so on. These kinds of events may also help drive public perception of climate change.

They’re interested in looking into different kinds of climate-related events in the future to see if the same effects apply.

“Coastal flooding is kind of a very noticeable, quite serious consequence of climate change — but it’s also something that’s becoming more and more frequent in certain areas along the coast as sea-level rise happens,” Moore said. “And so we are interested in extending this analysis to look at coastal flooding and … do we see that same kind of normalization happening over time, and if so, does that happen at the same rate?”