Story at a glance
- New research looks at historic high temperatures for the Pacific Northwest amid a severe heat wave.
- Scientists found that these record-breaking temperatures are likely driven by climate change, with a chance of occurring once in a millennium.
- Another heat wave is slated to hit southwestern U.S. regions.
The severe heat wave and drought overtaking parts of the U.S. west and nearby regions are continued symptoms of climate change, according to a new study, suggesting that such a heat wave wouldn’t be possible if human activity wasn’t causing the Earth’s temperatures to rise.
Scientists with the World Weather Attribution analyzed the changes in maximum temperatures in heat-struck regions, including cities like Portland, Ore., Seattle and Vancouver, British Columbia, all of which have seen record-high temperatures in the triple digits.
Based on the subsequent models and observations, researchers found that observed temperatures were such outliers in relation to historical averages that it would be about 150-times rarer without anthropomorphic climate change fueling it.
In other terms, these types of staggeringly hot temperatures in normally cool regions like the Pacific Northwest are about as rare as one in 1,000 years.
“An event such as the Pacific Northwest 2021 heatwave is still rare or extremely rare in today’s climate, yet would be virtually impossible without human-caused climate change,” the report reads. “As warming continues, it will become a lot less rare.”
Scientists also predict that should global temperatures increase by just 0.8 degrees Celsius warmer than current temperatures — reaching 2 degrees Celsius of global warming — temperatures in heat waves will continue to rise and stand to occur about every five to 10 years.
Some recorded temperatures stood as high as 116 degrees, which was seen in Portland. Seattle also recorded temperatures above 100 degrees — well past the average 70-degree temperatures usually seen in June.
The heatwave that overtook the Pacific Northwest and Western regions of the Americas had disastrous public health consequences, with many people dying of heat-related illnesses and hundreds being hospitalized with conditions like hyperthermia and dehydration.
Thanks to a meteorological formation known as a “heat dome,” warm and dry air was trapped in the troposphere above affected areas thanks to a slow-moving high pressure system passing over the region.
Extreme temperatures linked to climate change contributed to the severity of the warming within the heat dome that negatively affected human health.
Forecasters are saying a similar heat wave could resurface next week, this time near the southwestern states, including Southern California, Utah and Idaho.
“Although this was a rare event, it would have been virtually impossible in the past,” said Sarah Kew, a researcher with the Royal Netherlands Meteorological Institute, who worked on the report.