After a record fall, when nearly the entire United States experienced drought—unprecedented in US Drought Monitor history—water managers and planners nationwide are nervously hoping for a wet winter, cautious about prolonged dry spells that leave their communities vulnerable. … Climate models paint an alarming picture of escalating drought risks in many parts of the world as temperatures rise. But as sophisticated as these numerical models are, they may actually be underestimating the true risks from prolonged dry spells in a warming world. As a climate scientist who studies drought, I’ve spent years analyzing the projections of the global climate models that form the basis of reports from the Intergovernmental Panel on Climate Change. …. However, there’s a crucial aspect of drought risk that many models struggle to capture: natural variability from year-to-year and decade-to-decade.
—Written by Toby Ault, professor of atmospheric sciences at Cornell University