Finding safe haven in the climate change future: The Pacific Northwest

This Yahoo News series analyzes different regions around the country in terms of climate change risks that they face now and will experience in the years to come. For other entries in the series, click here.

As the negative consequences of rising global temperatures due to mankind’s relentless burning of fossil fuels become more and more apparent in communities across the United States, anxiety over finding a place to live safe from the ravages of climate change has also been on the rise.

“Millions and likely tens of millions of Americans” will move because of climate through the end of the century, Jesse Keenan, an associate professor of real estate in Tulane University’s School of Architecture, told Yahoo News. “People move because of school districts, affordability, job opportunities. There are a lot of drivers and I think it’s probably best to think about this as ‘climate is now one of those drivers.’”

In late October, a report by the United Nations concluded that average global temperatures are on track to warm by 2.1 to 2.9 degrees Celsius by the year 2100. As a result, the world can expect a dramatic rise in chaotic, extreme weather events. In fact, that increase is already happening. In the 1980s, the U.S. was hit with a weather disaster totaling $1 billion in damages (inflation-adjusted) once every four months, on average. Thanks to steadily rising temperatures, such a disaster now occurs every three weeks, according to a draft report of the latest National Climate Assessment, and these events aren’t limited to any particular geographical region.

To be sure, calculating climate risk depends on a dizzying number of factors, including luck, latitude, elevation, the upkeep of infrastructure, long-term climate patterns, the predictable behavior of the jet stream and how warming ocean waters will impact the frequency of El Niño/La Niña cycles.

“No place is immune from climate change impacts, certainly in the continental United States, and throughout the U.S. those impacts will be quite severe,” Keenan said. “They will be more severe in some places and less severe in other places. Certain places will be more moderate in terms of temperature and some places will be more extreme, but we all share the risk of the increase of extreme events.”

In this installment, we look at a region that in recent years has been forced to reckon with the misconception that it would be relatively safe from the ravages of climate change.

The Pacific Northwest

The catastrophic heat dome that descended over the Pacific Northwest during the summer of 2021 was unlike anything the region, which includes Washington, Oregon and Idaho, had experienced in living memory. It smashed temperature records by as much as 30 degrees Fahrenheit in some locations, left more than 1,000 people dead, and killed more than 1 billion sea creatures in the U.S. and Canada, transforming a region accustomed to mild summer weather into a kiln-like oven in which nighttime temperatures provided little relief.

Given the extremity of what was described as a 1-in-10,000-year heat event, it proved tempting for some who dismiss climate change as a “hoax” to discount the 2021 heat dome as a one-off, but then came the summer of 2022 and another deadly, albeit less severe, heat dome.

In late July, Portland, Ore., saw temperatures above 95°F for seven days straight, a new record. Seattle, where many residents don’t own an air conditioner, also set a new mark for enduring miserably warm weather, with more than six straight days of temperatures above 90°F. More than a dozen people in the region died from heat-related causes and dozens more were hospitalized.

For climate change deniers, hot summer temperatures are proof of nothing, even in regions unaccustomed to extreme heat. Less easy to discount, however, was what happened in autumn in the Pacific Northwest. On Oct. 16, Seattle broke its temperature record for that day by 16 degrees, hitting 88 degrees at a time of year when residents usually rely on sweaters and fleece to keep warm.

Portland hit 87°F on Oct. 15, one of seven high-temperature records set that month, and the city exceeded 80°F on 12 different days, double the previous record of six in the month of October.

The ratio of record-high temperatures to record-low ones is one of the clearest indicators that the planet is warming, and a 2009 study conducted by the National Center for Atmospheric Research found that new record-setting high temperatures were then outpacing new record-low temperatures by a ratio of 2:1. In the 13 years since that study was published, temperatures have continued to rise in places like the Pacific Northwest, and computer models have shown that that disparity will grow to 20:1 by 2050 and by 50:1 by 2100.

For the Pacific Northwest, the warming climate has also been resulting in a “dramatic decline in spring snowpack,” the Environmental Protection Agency states on its website, falling by 23% across the Western U.S.

“In the Northwest (Idaho, Oregon, Washington), all but three stations saw decreases in snowpack over the period of record (1955 to 2022),” the EPA says on its website. By the year 2080, the Cascade mountain range is expected to see an 80% reduction in its April snowpack, according to the most recent National Climate Assessment from the U.S. government.

The declining snowpack is already negatively impacting agriculture in the Pacific Northwest, altering the growing cycle of plants, and proving ruinous for fish populations in rivers and streams throughout the region.

“16,000 miles of Oregon rivers and streams have degraded water quality due to warmer temperatures, resulting in the loss of hundreds of thousands of sockeye salmon in the Columbia and Snake river basins alone,” the Nature Conservancy wrote about the Climate Assessment data.

Like many of his constituents in the Pacific Northwest, Sen. Jeff Merkley, D-Ore., has witnessed the impacts of climate change firsthand.

“We have a much longer, hotter fire season. The last Labor Day, a year ago, we had six towns burned to the ground, absolutely devastated, as if they’ve been firebombed,” Merkley told Yahoo News at the 2021 United Nations Climate Change Conference in Glasgow, Scotland.

“We have growing insect populations, pine beetles, that are destroying forests. Loss of snowpack in the Cascades, which means on one end, the recreation economy. But on the other end, it’s water for irrigation for our farmers, and water for our streams. Our streams are warmer and smaller, which affects our salmon and our trout.”

As Merkley noted, another consequence of warmer temperatures and the early season loss of the snowpack is the increased risk of wildfires. In October, smoke from a number of wildfires across the Pacific Northwest resulted in cities like Portland and Seattle having the worst air quality of any location on Earth.

“As the climate becomes warmer and drier,” the U.S. Forest Service says on its website, the forests of the Pacific Northwest “are experiencing longer fire seasons, larger burns, and increased wildfire risk.”

In 2020, the New York Times and ProPublica analyzed data provided by the Rhodium Group and ranked counties in the lower 48 states in terms of their relative safety from climate change risks. The analysis included six major categories — heat stress, the combination of heat and humidity (wet bulb), crop loss, very large fires, sea level rise and economic damages — and rated each county on the impact climate change would have on them given two emissions scenarios: high and moderate.

For the Pacific Northwest, the worst-ranked counties were spread out across the three states that make up the region, with the risk of very large fires factoring highly in each. Three of the 10 worst-ranked counties (Owyhee, Elmore and Ada) are found in Idaho. Four are in Oregon (Malheur, Morrow, Grant and Umatilla), and three others (Grant, Benton and Yakima) are in Washington.

Oregon’s Curry County, which is located on the coast, took the top spot on the list of 10 safest places to live in the Pacific Northwest when it comes to climate change risks, and is rated as 20th safest county overall in the lower 48 states. Idaho’s Madison and Lewis counties took the next two top spots in the Pacific Northwest and ranked as the 25th and 26th safest counties overall in the lower 48 states in terms of climate change risks. Rounding out the top 10 safest counties in the Pacific Northwest, four are in Idaho (Latah, Caribou, Bannock and Benewah), two are in Oregon (Columbia and Benton) and one is in Washington (San Juan).

What has become daunting for many residents of the Pacific Northwest in recent years is the scale of the changes being felt in what had been perceived as a stable region.

“Certainly on the West Coast, it’s on people’s minds, with the heat waves and flooding and especially the wildfires,” Jon Reeves, a psychologist based in Seattle who treats patients for climate anxiety, told Yahoo News earlier this year.

“With the heat dome, I noticed that people struggled to sleep because a lot of homes don’t have air-conditioning, and heat tends to exacerbate suicidality, anger and aggression,” Reeves said. “So folks were on edge and making mistakes at work because they’re not getting sleep. Everything felt a bit more tense the week it was really hot.”

In the short term, anyway, advances in meteorology do give us a fairly accurate picture of when we can expect extreme weather events to hit and when the risk of wildfire danger is elevated.

“We’re not losing the ability to predict weather or extreme events really. In fact, if anything, our ability is improving incrementally over time. But if we’re talking about predicting large-scale shifts over decades, I still think we’re kind of behind the curve,” UCLA climate scientist Daniel Swain told Yahoo News. “We can’t always represent those changes very well because we don’t always understand them.”

As an example, Swain cites the Clausius-Clapeyron equation, which describes the increase in atmospheric moisture as well as the accelerated rate of evaporation that results from every degree of temperature rise.

“I think we’ve underestimated how profound an influence Clausius-Clapeyron is going to have on everything, not just extreme precipitation,” Swain says.

As with other regions of the country, Clausius-Clapeyron is likely already impacting the Pacific Northwest in numerous ways.

In 2021, just months after the heat dome gripped the region, western parts of the U.S. and Canada were struck by devastating floods caused by a 1-in-500-year rain event that displaced more than 20,000 people from their homes. Such extreme rainfall events will become more common thanks to climate change, studies have shown.

“We have to realize that we’re going to face decades of increased floods in our state of Washington,” Gov. Jay Inslee, a Democrat, said at a press conference about the days-long deluge.

While most media outlets have focused on the finding that for every degree Celsius of warming, the Earth’s atmosphere holds 7% more moisture, dramatically increasing the likelihood of an extreme rainfall event, Swain believes that another consequence of rising temperatures could prove even more impactful.

“The Clausius-Clapeyron relationship also increases what is known as the vapor pressure deficit,” he said, which means that “the atmosphere’s potential to act as a giant sponge and extract more water out of the landscape has increased, even if the relative humidity has stayed the same. This Clausius-Clapeyron relationship is actually what drives the atmosphere’s capacity to dry out the landscape faster.”

All of this is already happening across the Pacific Northwest even though the average temperature in the region rose by just 1.3°F between 1895 and 2011. But as we have continued to pump more greenhouse gases into the atmosphere, the rate of temperature rise has also increased. By 2070, average temperatures are expected to rise by as much as 9.7°F, according to the Third National Climate Assessment.

If that trajectory holds steady, the Pacific Northwest is all but guaranteed to experience heat dome events as severe as the one in 2021, a new study published in the journal Nature Climate Change concluded.

“Since the 1950s, global warming has transformed the peak daily regional temperature anomaly of the event from virtually impossible to a presently estimated ~200-yearly occurrence,” the study states. “Its likelihood is projected to increase rapidly with further global warming, possibly becoming a 10-yearly occurrence in a climate 2 °C warmer than the pre-industrial period, which may be reached by 2050.”