PORTLAND, Ore. (KOIN) — The Pacific Northwest reached such high temperatures in the summer of 2021 that climate scientists say similar events typically occur once in 10,000 years.

Karen McKinnon, assistant professor at UCLA’s Institute of the Environment and Sustainability, co-authored a study with Isla Simpson from the National Center for Atmospheric Research to determine whether last year’s unprecedented and deadly heat dome could be the new normal.

In particular, the study notes how the last days of June 2021 caused an uptick in heat-related deaths, emergency department visits, wildfires, buckled roads and more. 

Beating the heat isn’t as simple as staying inside; many homes in the PNW don’t have air conditioning due to the region’s usual moderate climate. During this summer’s heat advisory, the Oregon State Medical Examiner’s Office received tragic reports of several potential heat-related deaths.

Although, this isn’t the first time the PNW has experienced high temperatures in the summer months. 

The study points out, “For example, between 1901 and 2009, stations in the western half of Washington and Oregon recorded 12 events during which daily maximum temperature anomalies exceeded 10°C (actual temperatures between 28°C and 40°C. Depending on the location), with no significant trend in frequency, magnitude or duration of extreme events over this period.” 

Even without climate change, the PNW would have experienced extreme weather conditions, the study states. However, 2021’s heat wave wasn’t only caused by meteorological factors, according to the research: human activity also has a big impact on climate change.

According to NASA, “The industrial activities that our modern civilization depends upon have raised atmospheric carbon dioxide levels by nearly 50% since 1750. This increase is due to human activities, because scientists can see a distinctive isotopic fingerprint in the atmosphere.”

More recently, Portland has continued to break long-standing weather-related records. In early September 2022, KOIN 6 meteorologist Kelley Bayern reported that most of the city’s heat records had been broken just in the previous 20 years.

Overall, climate models throughout history have resembled that of summer 2021. The study reveals that while the latest heat waves are rare, they could become more probable in the future.