Last summer, the Pacific Northwest of the United States was experiencing a record-breaking heat wave when a woman in her 70s was wheeled into an emergency room with symptoms of a life-threatening heat stroke.

Dr. Alexander St. John snatched a body bag from the hospital kitchen, filled it with ice from the kitchen, and zipped the woman inside. Her body temperature dropped within minutes, and her symptoms improved.

“I’ve never had to do anything like that before. “It was surreal,” St. John said. “Twenty years ago, it appears that we would talk about climate change as something that would happen over the next generation — and now it appears to be accelerating to the point where we’re all experiencing it in real time.”

Several other patients were saved using this technique at Seattle’s Harborview Medical Center during a five-day heat wave last June that saw temperatures reach 118 degrees Fahrenheit in some places and killed an estimated 600 people or more across Oregon, Washington, and western Canada.

According to a United Nations report released this week, the sweltering stretch across the normally cool region provides a glimpse of the types of extreme weather events that will accelerate in North America within 30 years unless a coordinated effort to slow climate change is made. Even if global warming is limited to 1.5 degrees Celsius, people in the United States, Mexico, and Canada will be increasingly vulnerable to catastrophic weather events.

The Intergovernmental Panel on Climate Change report details how rising temperatures will endanger people’s health, cause food insecurity, cause economic upheaval, and force migration from increasingly uninhabitable areas. According to the report, low-income and minority populations will be the hardest hit, exacerbating existing inequities.

The report predicts worsening drought, extreme heat, and wildfires in the West. More destructive hurricanes and rising sea levels are expected to hit the Gulf Coast. Heavy rains are expected to cause more flooding and crop damage in the Midwest and Northeast.

Flooding in the Midwest and South of the United States disrupted barge traffic on the Mississippi River and damaged cropland in Ohio and Indiana in the summer of 2019. Offutt Air Force Base in Nebraska had been crippled by a different downpour and flood months before.

The economic consequences will be significant. Warming water and acidification of the oceans will disrupt commercial fisheries, extreme heat will result in lower yields of key crops such as corn and soybeans, and drought will result in livestock losses as animals have less ground to forage, according to the report.

According to the National Oceanic and Atmospheric Administration, there have been 35 floods in the United States that have caused more than $1 billion in damage since 1980, with more than half of those occurring since 2010.

Following last summer’s deadly heat wave, Portland officials are considering alarm systems in public housing that would notify building managers when temperatures exceeded 100 degrees Fahrenheit. In addition, city officials approved a plan to distribute 15,000 heat pumps, which are an energy-efficient way of cooling spaces. Legislators in Oregon are also considering a $15 million investment in distribution air purifiers, air conditioners, and heat pumps.

Longer-term discussions in the Pacific Northwest and elsewhere include painting roof tops white and using lighter-colored pavement to repel sunlight, planting more trees in urban areas, and creating neighborhood cooling hubs that can also serve as social gathering places.

Renee Salas, an emergency room doctor and fellow at Harvard University’s Center for Climate, Health, and the Global Environment, noted that health risks are increasing not only from heat, but also from worsening wildfires that send smoke plumes thousands of miles across North America, and rising temperatures that could foster the spread of diseases spread by mosquitoes and ticks like dengue fever, West Nile, and Lyme disease.

Adaptation will entail treating climate change as a secondary diagnosis for many patients, according to Salas. In the future, doctors may write prescriptions for air purifiers or heat pumps in the same way that they do for medications, and a national system of health records may help patients who become climate refugees receive consistent medical treatment.