|Wednesday, May 2, 2012 - 7:00 AM
"Medieval Drought in the Southwest"
Between roughly 900 and 1260 AD there was a massive drought that severely impacted the plants, animals and people of the Southwest. Now referred to as the Medieval Drought, the best records of this phenomenon can be found within the trees that lived through this difficult time period. Host David Yetman hikes with Tom Swetnam from the University of Arizona's Laboratory of Tree-Ring Research through the White Mountains of California and Sequoia National Park to observe how scientists use tree rings to gather evidence of climate conditions from thousands of years ago. D