Floodwaters slowly recede in the aftermath of Hurricane Ida in Lafitte, Louisiana, Wednesday, Sept. 1, 2021.

New IPCC report says climate change poses an extreme risk to billions of people

Climate change could be disastrous for human civilization, warns a new report from the United Nations Intergovernmental Panel on Climate Change.

Floodwaters slowly recede in the aftermath of Hurricane Ida in Lafitte, Louisiana, Wednesday, Sept. 1, 2021.

Gerald Herbert/AP

The latest report from the United Nations Intergovernmental Panel on Climate Change warns that the climate emergency is at risk of becoming a disaster for human civilization.

The world has heard these warnings since 1990, but this latest assessment provides even more stark detail about how billions of people are highly vulnerable to the disruptive and dangerous effects of global warming.

The report spells out the impacts that climate change is causing already and will continue to cause to humans and to ecosystems. UN Secretary General Antonio Guterres said in a statement that the report is an “atlas of human suffering and a damning indictment of failed climate leadership.”

“[H]eat waves are already becoming more intense and occurring more often, and when they occur people die."

Michael Oppenheimer, Princeton University

“[H]eat waves are already becoming more intense and occurring more often, and when they occur people die,” says Michael Oppenheimer, professor of geosciences and international affairs at Princeton University. Oppenheimer was a review editor for the Sixth Assessment by the IPCC.

“The largest cause of climate-related mortality in the United States is heat-related death,” he says. 

There is a limit to the body's ability to dissipate heat, Oppenheimer explains. At a certain point, the combination of heat and humidity is so high that people cannot cool themselves by perspiring, so they “can't carry on normal outdoor activities without risking death,” he says.

This already occurs in certain parts of the world — for example, in the Persian Gulf region, Oppenheimer notes. But the number of regions where it will be too hot and humid on some days to go outside and engage in ordinary human activities — construction, farming, athletics, etc. — is going to grow from relatively few to many more over time.

“There are places in the US that are going to suffer that combination of high heat and high humidity, so that outdoor activity — beyond just kind of lying there — is simply not going to be possible without taking your life in your hand."

Michael Oppenheimer, Princeton University

“There are places in the US that are going to suffer that combination of high heat and high humidity, so that outdoor activity, beyond just kind of lying there, is simply not going to be possible without taking your life in your hand,” Oppenheimer says. “That's the kind of change we're looking at in many areas.”

For Americans, the extreme heat wave in the Pacific Northwest last summer is a good example of this disturbing trend, Oppenheimer says. About 200 people died in Washington, Oregon, and southwestern Canada, a region unaccustomed to hot weather, where few homes have air conditioning and where temperatures rose much higher than at any other time in recent history.

"Scientists were able to look at that event and say, ‘There's no question about it: That would not have happened without the buildup of the greenhouse gases and climate change,’” Oppenheimer says.

It’s going to happen again and it’s probably going to happen a lot more frequently than before, Oppenheimer warns. So now, the question for the residents of those areas is, “how are we going to protect people? How are we going to keep hundreds of people from dying? Because next time it might be thousands of people." 

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Many urban areas in the US and other countries are changing building codes in ways that will lessen the impacts of extreme heat — painting an aluminum color on roofs, for example, because the paint reflects sunlight, or insulating roofs better to keep heat in during the winter and keep it out in the summer.

“For some parts of the climate problem, like extreme heat, we've privatized it. We go around assuming everybody can get air conditioning. But a lot of people are poor. They can't afford air conditioning."

Michael Oppenheimer, Princeton University

“But one thing I'm really worried about are that these are all sort of decisions that have to be made cooperatively. They’re collective decisions or governmental decisions,” Oppenheimer says.

“For some parts of the climate problem, like extreme heat, we've privatized it. We go around assuming everybody can get air conditioning. But a lot of people are poor. They can't afford air conditioning. Or if there's a blackout because of a heat wave, because of too much draw, then everybody’s stuck without air conditioning. And we've made almost no preparation for those kinds of people or that kind of eventuality.”

The IPPC report estimates that if the world continues emitting greenhouse gases at their current rate, at least 1 billion people are at risk of losing their homes as a result of climate change by 2050. This includes not just coastal regions affected by sea-level rise, but regions where farmers can no longer depend on the consistency of the seasons for agricultural production and move the whole household elsewhere.

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These are things that are not just happening "somewhere else" in the world, Oppenheimer points out. In some areas of the US, coastal regions are sinking and the government is offering buyouts of homes.

“They’re voluntary, but what's left behind is a community which is no longer functional in some cases, and somebody has to make a decision essentially to turn off the lights at a certain point,” he notes. “That whole process of easing transitions for people, for households and for communities is something our government has only partially grappled with in the United States. That has to be thought about more carefully.”

In certain areas that are “geologically possible to protect,” like Savannah, New York, and Boston, “it will be possible to spend a lot of money — and I mean a lot of money — building infrastructure like sea walls and surge barriers that will protect those places,” Oppenheimer says. But in places that have neither the money nor the political clout to get it, people will have to move away from the coast. “There is no other option,” he insists.

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“The estimate of a billion people being displaced overall — I think that's a very soft estimate,” Oppenheimer says. “We really don't know. But the point is, if we sit here and do nothing, we'll make it a reality. What we have to do is start thinking ahead, do that planning on, you know, 30, 40, 50 years ahead. That can work and keep displacement to a minimum.”

This article is based on an interview by Jenni Doering that aired on Living on Earth from PRX.