A new analysis by Gallup in collaboration with Citi, shared first with CNN, found that people who experienced extreme heat – days that were significantly hotter than normal – also reported a decrease in their sense of well-being around the same time. On average, the global population experienced three times as many extreme heat days in 2020 than it did in 2008, Gallup reported, and well-being decreased globally by 6.5% in that time as well.
Researchers also found that because the climate crisis is pushing temperatures even hotter, global well-being could decrease by another 17% by the end of this decade.
“This study is a new way of looking at how climate change impacts humans around the world,” said Nicole Willcoxon, Gallup’s research director for the project. “And while there are many factors that impact people’s well-being, this study demonstrates that there is a clear relationship between rising temperatures and declines in life evaluation.”
Extreme heat has been relentless across the Northern Hemisphere this summer. In May, Pakistan and India faced scorching temperatures that scientists say will become 100 times more likely as the climate crisis advances. Then in July, Europe and the UK faced record-breaking heat. At the same time, blistering temperatures continue to rip across China and parts of the United States – including the West, which is gearing up for a searing heatwave this week.
Gallup’s global study shows how much of an impact that heat has on our lives, whether or not we realize it.
Over 15 years, Gallup surveyed 1.75 million people across 160 countries and asked them about their sense of well-being. Using temperature data from NASA, researchers looked at extreme heat in the 30 days before respondents were interviewed and then compared that to their life-evaluation responses.
A single extreme heat day was associated with an average well-being decrease of 0.56%.
“It’s important set of findings for leaders to consider as they’re evaluating the impact of climate change,” Willcoxon said. “I think there’s a lot of focus on the economic effects, the focus on what kind of extreme weather might occur – but then, what is the outcome of that and how are people going to be impacted?”
The impact on well-being is more significant among older generations than young, Gallup researchers found, and among those living in countries with developing economies – where people are less equipped to handle the economic toll of the climate crisis – such as China and Brazil. Over the past decade, these countries have been wracked by environmental justice issues and climate change-fueled extreme weather events.
The report also noted people living in the southernmost regions of many nations are at increasing risk of sweltering temperatures and its associated decline in well-being, including residents along the US Gulf Coast as well as China, both of which experienced at least 10 high-heat days in the month prior being surveyed.
Researchers also linked warming temperatures and related disasters like drought to major conflicts and food insecurity – both of which can propel people from poorer and hotter countries to migrate to wealthier nations in cooler climates.
When Gallup surveyed the Mekong River Delta region in Vietnam, for instance, they saw life ratings declined 11% between April 2015 and June 2016 – a time when the region suffered its worst drought in decades. As the region dried up, saltwater intrusion from rising sea levels devastated their cropland, which increased food insecurity and exacted a toll on the economic health of the region.
“The [available] climate research shows that there’s a clear risk for mass migration, social divides and inequality increasing, potential food crises and things like that,” Willcoxon said. “While this study didn’t directly measure those things, we think it’s a clear implication out of the [available] research showing that if well-being continues to drop at the levels that we project, it could exacerbate these issues even more deeply, or that it’s a piece of the puzzle that we’re missing at this point of what is the human toll.”
Mental health in a warmer future
While the report found well-being could fall by another 17% over the next eight years, researchers said that forecast doesn’t take into account the world’s ability to adapt to the climate crisis and recover from extreme heat.
Robbie Parks, environmental epidemiologist and incoming assistant professor at Columbia University’s Climate School, said the poll is an effective way to prod decisionmakers to “pull the right levers” on climate action.
“While people understand that climate change is awful in so many ways, when people start to understand how it affects their daily lives – and particularly their health and well-being – I find that is a really good stimulant to political motivation for action and change,” Parks, who is not involved with the research, told CNN.
The World Meteorological Organization recently reported an extreme weather event had occurred every day on average somewhere in the world over the last 50 years, a five-fold increase in frequency over that period. And polls have helped illuminate how extreme weather and environmental degradation is affecting moods. A Gallup survey earlier this year found that only 39% of Americans were satisfied with the quality of environment in the US.
“We’ve got a lot to build on here,” Willcoxon said. “As we project that we’re going to see a lot more high temperature days and extreme weather events, looking at that and tracking that over time will be really important and key to providing the data that policymakers and leaders need to help provide solutions for this issue.”