Columbia University

Drought management in the U.S. hinges on the quality of our drought monitoring, which is a challenge in a changing climate. The United States Drought Monitor (USDM), a key tool for identifying and categorizing droughts since 2000, uses different categories to describe the intensity of droughts, such as “moderate,” “severe,” or “extreme.” These categories help decision-makers understand how bad a

Arid and semi-arid areas may face especially high risks of extreme heat and fire.The laws of thermodynamics dictate that a warmer atmosphere can hold more water vapor, but new research has found that atmospheric moisture has not increased as expected over arid and semi-arid regions of the world as the climate has warmed.The findings are particularly puzzling because climate models have been

Key Findings Megadroughts are persistent, multi-year drought events that stand out as especially extreme in terms of severity, duration, or spatial extent when compared to other droughts of the last two thousand years Megadroughts have occurred on every continent outside of Antarctica, often causing major disturbances to ecosystems (e.g., forests in the Southwest U.S.) and societies (e.g

At the end of summer 2021, the U.S. Drought Monitor reported 90% of the West in drought with 54% in Extreme Drought (D3) or Exceptional Drought (D4). Reservoir levels were low across almost the whole West, including the Colorado River Basin's Lakes Powell and Mead at just 31% and 35% of capacity, respectively. Multiple states rated most of their rangelands and pasture in poor to very poor