Studying tree rings has revealed a record of wet and dry times that helps make sense of the mysterious and gradual demise of Angkor, the capitol of the Khmer Empire in Cambodia from the 9th to 14th centuries. A very wet period with rich monsoons and plentiful crops from 1258 to 1300 was followed by many years of drought from 1350 to 1370.
Image Courtesy of Zina Deretsky, National Science Foundation