Climate change will damage the economies of countries whether they are rich or poor, hot or cold, by the year 2100, economists wrote in a new report, dispelling the notion that impoverished, warm countries will suffer the most on a warming planet.

Researchers who examined data from 174 countries over 50 years found that persistent temperature changes above or below a country’s historical norm adversely affected economic growth, regardless of how warm the country is.

The United States could see a 10 percent loss in gross domestic product without significant policy change according to the study, which was published Monday by the U.S. National Bureau of Economic Research, a nonprofit economic research organization.

Researchers from the University of Cambridge, University of Southern California, Johns Hopkins University, and the National Tsing Hua University in Taiwan, as well as the International Monetary Fund, contributed to the report.

“In the U.K. we had the hottest day (ever) recorded a few days ago and infrastructure came to a halt,” said Kamiar Mohaddes, a co-author of the report and a professor of economics at Cambridge University, in an interview on Tuesday.

“Trains aren’t running, people aren’t coping, and therefore productivity and economic growth falls.”

Research has often focused on short-term devastation to poor, warm countries, but the study suggests that wealth and cooler temperatures are no protection from climate change’s economic toll if major policy changes are not adopted.

In a “business as usual” scenario, in which the greenhouse gas emissions that cause climate change are not drastically lowered, the average global temperatures will increase by 4 degrees Celsius (7.2 degrees Fahrenheit) by the year 2100.

That would bring more than a 7 percent loss in world GDP per capita, the study found.

The 2015 Paris Agreement, a global pact to fight climate change agreed by nearly 200 countries, aims to keep the Earth’s temperature rise well below 2 C (3.6 F) while striving for 1.5 C (2.7 F).

But even that would require a radical reduction of greenhouse gas emissions, a landmark U.N. report found last year.

The economists’ research focused on the United States, due to its varied climates, and found that ignoring the Paris accord’s goals would affect industries from manufacturing to agriculture, costing the U.S. more than 10 percent of its GDP per capita.

“The average American household will be poorer,” Mohaddes said, noting that other industrialized countries could be similarly impacted.

Canada, which is warming twice as fast as the rest of the world, could expect a 13 percent loss in income, while Switzerland could see a 12 percent cut and India would see a 10 percent drop in GDP per capita.

On the other hand, adhering to the Paris Agreement goals could hold the loss in the United States to under 2 percent, the report said.

U.S. President Donald Trump vowed in June, 2017, to pull the United States out of the international agreement, dealing a major blow to efforts to limit climate change. The earliest that withdrawal could take effect is November 2020.

The report also suggested that while some countries are likely to adapt to climate change, they are unlikely to act in time to ward off all the negative effects to their economies.

“We need to have much stronger mitigation,” said Mohaddes. “If we do commit to Paris, the losses are substantially lower. It’s not too late.”