Scientific studies calculate climate change as health danger, while Trump calls it a 'scam'

The Trump administration on Thursday revoked a scientific finding that climate change is a danger to public health, an idea that President Donald Trump called “a scam.” But repeated scientific studies say it’s a documented and quantifiable harm.

Again and again, research has found increasing disease and deaths — thousands every year — in a warming world.

The Environmental Protection Agency finding in 2009, under the Obama administration, has been the legal underpinning of nearly all regulations fighting global warming.

Thousands of scientific studies have looked at climate change and its effects on human health in the past five years and they predominantly show climate change is increasingly dangerous to people.

Many conclude that in the United States, thousands of people have died and even more were sickened because of climate change in the past few decades.

For example, a study on “Trends in heat-related deaths in the U.S., 1999-2023 ” in the prestigious JAMA journal shows the yearly heat-related death count and rate have more than doubled in the past quarter century from 1,069 in 1999 to a record high 2,325 in 2023.

A 2021 study in Nature Climate Change looked at 732 locations in 43 countries — including 210 in the United States — and determined that more than a third of heat deaths are due to human-caused climate change. That means more than 9,700 global deaths a year attributed to warming from the burning of coal, oil and natural gas.

A new study published this week found that 2.2% of summer deaths in Texas from 2010 to 2023 were heat related “as climate change brings more frequent and intense heat to Texas.”

Research is booming on the topic

It's been a much-researched topic.

In the more than 15 years, since the government first determined climate change to be a public health danger, there have been more than 29,000 peer-reviewed studies that looked at the intersection of climate and health, with more than 5,000 looking specifically at the United States, according to the National Library of Medicine's PubMed research database. More than 60% of those studies have been published in the past five years.

“Study after study documents that climate change endangers health, for one simple reason: It’s true,” said Dr. Howard Frumkin, professor emeritus of public health at the University of Washington and a former director of the National Center for Environmental Health appointed by President George W. Bush.

“It boggles the mind that the administration is rescinding the endangerment finding; it’s akin to insisting that the world is flat or denying that gravity is a thing.”

In a Thursday event at the White House, Trump disagreed, saying: “It has nothing to do with public health. This is all a scam, a giant scam.”

Experts strongly disagree.

“Health risks are increasing because human-cause climate change is already upon us. Take the 2021 heat dome for example, that killed (more than) 600 people in the Northwest,'' said Dr. Jonathan Patz, a physician who directs the Center for Health, Energy and Environmental Research at the University of Wisconsin-Madison. "The new climate attribution studies show that event was made 150-fold more likely due to climate change.”

Patz and Frumkin both said the “vast majority” of peer-reviewed studies show health harms from climate change. Peer-reviewed studies are considered the gold standard of science because other experts pore over the data, evidence and methods, requiring changes, questioning techniques and conclusions.

More than just heat and deaths

The various studies look at different parts of health. Some looked at deaths that wouldn't have happened without climate change. Others looked at illnesses and injuries that didn't kill people. Because researchers used different time periods, calculation methods and specific aspects of health, the final numbers of their conclusions don't completely match.

Studies also examined disparities among different peoples and locations. A growing field in the research are attribution studies that calculate what proportion of deaths or illness can be blamed on human-caused climate change by comparing real-world mortality and illness to what computer simulations show would happen in a world without a spike in greenhouse gases.

Last year an international team of researchers looked at past studies to try to come up with a yearly health cost of climate change.

While many studies just look at heat deaths, this team tried to bring in a variety of types of climate change deaths — heat waves, extreme weather disasters such as 2017's Hurricane Harvey, wildfires, air pollution, diseases spread by mosquitos such as malaria — and found hundreds of thousands of climate change deaths globally.

They then used the EPA's own statistic that puts a dollar value on human life — $11.5 million in 2014 dollars — and calculated a global annual cost “on the order of at least $10 billion.”

Studies also connect climate change to waterborne infections that cause diarrhea, mental health issues and even nutrition problems, Frumkin said.

“Public health is not only about prevention of diseases, death and disability but also well-being. We are increasingly seeing people displaced by rising seas, intensifying storms and fires,” said Dr. Lynn Goldman, a physician and dean emeritus at the George Washington University School of Public Health.

“We have only begun to understand the full consequences of a changing climate in terms of health.”

Cold also kills and that's decreasing

The issue gets complicated when cold-related deaths are factored in. Those deaths are decreasing, yet in the United States there are still 13 times more deaths from cold exposure than heat exposure, studies show.

Another study concludes that until the world warms another 2.7 degrees (1.5 degrees Celsius) from now, the number of temperature-related deaths won't change much “due to offsetting decreases in cold-related mortality and increases in heat-related deaths.”

But that study said that after temperatures rise beyond that threshold, and if society doesn't adapt to the increased heat, “total mortality rises rapidly."

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