Arizona Science

Arizona Science explores the latest scientific research and technological innovations taking place in Southern Arizona and at the University of Arizona. Catch Arizona Science each Friday during Science Friday on NPR 89.1.


Episode 189: Tree ring research tracks the history of the Asian monsoon

Nearly half the world's population is affected by the Asian summer monsoon, but the monsoon has been weakening since the 1940s. Instrumental and observational records go back about 100 years, but University of Arizona tree ring researcher Steven Leavitt has tracked the monsoon's history 450 years into the past to uncover previous trends in rainfall and drought. His study found that the 80-year decline in rainfall is unprecedented, and traced it to the impact of man-made atmospheric pollutants.


 2019-07-03  5m