Unprecedented 'Hot Drought' in Western North America

Recent study reveals the past two decades have been among the warmest in five centuries, intensifying drought conditions.

Research suggests that the concurrent heat and drought conditions, known as 'hot drought,' have been unprecedented in frequency and severity over the past century across western North America.
Tree-ring chronologies used to map summer maximum temperatures from 1553 to 2020 show that the past two decades have been among the warmest in five centuries across much of the western United States.
High temperatures have amplified soil moisture deficits, contributing significantly to the frequency, intensity, and spatial extent of drought conditions.
Regions such as the Great Plains and the Colorado River basin, historically prone to severe hot drought, are now more strongly influenced by high temperatures.
The increasing prevalence of hot drought has important implications for future regional climate change adaptation strategies and water resource management, particularly in the most historically drought-prone regions.