Heat-related deaths in the Northwest will continue to increase in coming years "across all scenarios," according to the recently released Fifth National Climate Assessment.
The congressionally mandated report on the effects of human-caused climate change is released every four years. The latest edition paints a dire picture across the country, but focuses on the increasing risk of fire, smoke and drought in Washington, Idaho and Oregon.
Heat and wildfires were the cause of thousands of deaths in the three states in the past five years. Most deadly in that time was the 2021 heat dome, which was "partially attributed to climate change," according to the assessment.
The effects of wildfires were experienced in Eastern Washington just this past summer with the Oregon Road and Gray fires in Spokane County. Together, those fires burned more than 20,000 acres and destroyed a combined 366 homes and 710 structures.
It remains unknown whether the 2021 heat dome was an "anomaly or will become increasingly frequent," but heat-related deaths in the Northwest are expected to increase in either case.
"The western US is warming faster than the eastern US, and we're seeing an increase in the frequency and severity of extreme events in the western US at a faster rate than they are in the US as a whole," said Washington State University professor Deepti Singh, who is one of the co-authors of the assessment.
Wildfires in the western United States are part of a national trend of increasing natural disasters. There was a billion-dollar disaster every four weeks in the 1980s, and a billion-dollar natural disaster every three weeks now.
In 2022 alone, the United States experienced 18 weather and climate disasters with damages exceeding $1 billion.
The world is on track for a central warming estimate of approximately 2.6 degrees Celsius (36.7 degrees Fahrenheit) by 2100.
Annual temperatures in the Northwest have increased by approximately 2 degrees Fahrenheit since 1900. Washington and Idaho have warmed just below that figure, while Oregon has warmed by 2.5 degrees in the same time frame.
Over the next 50 years, the annual average temperature in the three states is expected to increase by an average of between 4.7 degrees and 10 degrees. Whether warming is on the low or high end of this range by the 2080s depends upon assumptions made about the human response to the climate and other factors.
"We have seen a decline in emissions over the past decade from the U.S. Even though we need to be reducing more aggressively. We have the tools — we have the knowledge that we need to reduce carbon, and we're moving in the right direction. We just need to be moving a lot faster," Singh said.
Because of increasing temperatures in the Northwest, summer precipitation will decline "under all scenarios," causing "more frequent, longer, and more severe regional drought conditions."
"Population growth and droughts are expected to amplify competing claims to the water supply by irrigators, Tribes, power plants, and other water rights holders," the report states.
These prolonged droughts will lower the streamflow of rivers and other water sources in the Northwest. Glaciers will also recede, causing more landslides.
The increased smoke from wildfires is projected to cause many long-ranging health impacts for those living in the Northwest, even if they are not directly affeced by wildfires. Washington is expected to see an increase of 25.7 wildfire smoke-related emergency room visits per 10,000 persons by the 2050s. Oregon and Idaho could see an increase of 41.9 and 29.4 ER visits per 10,000 residents, respectively.
The assessment states smoke is expected to be most severe in Eastern Washington, North Idaho and Oregon — especially those areas most populated.
"The anticipated financial burden of healthcare costs associated with wildfire smoke exposure is expected to significantly increase across the Northwest," reads the report, noting that wildfire smoke is associated with a predisposition to COVID-19 and an increase of asthma-related incidents.
According to the assessment, marginalized communities in the Northwest will be most susceptible to the harm caused by climate change in the coming decades. This includes urban communities of color, rural and natural resource-dependent communities and tribal and Indigenous communities.
"These communities are disproportionately vulnerable — meaning they will contribute less to causing climate change but are being affected much more," Singh said.
"In the Northwest, those are communities of color, rural community and Indigenous people whose lives, livelihood and culture are being pretty drastically affected by climate change already. As we move forward, we need to be centering these communities in our action to make use more resilient to changes in the climate," she said.
Asked what makes her hopeful while studying climate change, Singh pointed to the ways communities have adapted to reduce emissions and also protect themselves compounding natural disasters that are here and will get worse.
"It is maybe not sufficient to completely reduce the risks of climate change, but communities are adapting to reduce greenhouse gas admissions and reduce climate change," she said.