Research suggests 'high temperature drought' in western North America unprecedented since 16th century
![](https://news.climate.columbia.edu/wp-content/uploads/2024/01/DSC_0090-637x422.jpg)
![](https://news.climate.columbia.edu/wp-content/uploads/2024/01/DSC_0090-637x422.jpg)
In addition to a lack of rainfall, more heat is drying out the soils of western North America, researchers say. (Photo: Kevin Krajick/Earth Institute)
A reconstruction of summer temperatures in western North America over the past 500 years suggests that simultaneous heat and drought conditions, known as „hot droughts,“ have been unprecedented in frequency and severity over the past century. has been done. This finding was obtained based on tree-ring chronologies that show how changes in temperature are related to changes in soil moisture. These add to the evidence that human-induced warming is exacerbating climate extremes across the region.
This study was conducted by researchers at Columbia University. Lamont-Doherty Earth Observatory and other institutions; just published in diary scientific progress.
Researchers have documented increasingly hotter and drier conditions across western North America over the past two decades, often linking them to anthropogenic warming.This too 2020 survey It employs data dating back to the 800s that shows the human influence on current droughts. However, the lack of independent long-term temperature records to compare with long-term soil moisture records has made it difficult to discern whether the recent prevalence of hot droughts exceeds natural variability in the region. There is.
In the new study, the lead author Karen King The research team used an extensive network of tree-ring dates to map maximum summer temperatures in western North America from 1553 to 2020. Combining these reconstructions with existing data on drought conditions, the researchers found that the past 20 years have been among the warmest in the past five centuries for much of the western United States. The researchers found that high temperatures appear to amplify soil moisture deficits and significantly contribute to the frequency, intensity, and spatial extent of drought conditions.
They point out that while regions such as the Great Plains and Colorado River Basin have historically been prone to severe high-temperature droughts, these past events were not as strongly affected by high temperatures as they are today. The findings suggest that land-atmosphere interactions may play a more important role in the severity of recent megadroughts than past megadroughts.
“The prevalence of high temperature droughts has been increasing for 20 years;th and 21cent „Climate change over centuries has important implications for future regional climate change adaptation strategies and water resource management, especially in historically most drought-prone regions,“ the authors write. .
Co-authors of the study include Edward Cook, Benjamin Cook, Jason Smerdon and Richard Seager of Lamont-Doherty. Kevin Antukaitis of the University of Arizona. Grant Hurley and Benjamin Spey of the University of Idaho; Karen King was previously a postdoctoral fellow at Lamont-Doherty University and is currently at the University of Tennessee, Knoxville.
Based on a press release by Science Advances.