Dr. MacDonald studies climate change and its impacts on societies, with a particular focus on drought and water resources. His current projects include work in California, Utah, northern Canada, Russia, Egypt and India. He has published over 130 peer-reviewed journal articles as well as a number of book chapters. The Association of American Geographers recognized his 2002 textbook, Biogeography: Introduction to Space, Time and Life with the Cowles Award for Excellence in Publication. As well as being named University of California Presidential Chair, and being recognized with numerous other honors, MacDonald is a Fellow of the American Association for the Advancement of Science, and currently serves on the Geographical Sciences Committee of the National Academy of Science.
As global warming proceeds over the 21st century the semi-arid regions of the world may face a daunting sustainability challenge in the form of decreased water resources. In many areas, including the Southwestern United States, the 21st has already been unusually warm and arid relative to the 20th century. Archaeological and ancient historical records show that many of the same regions which are becoming arid today have experienced episodes of prolonged aridity in the past, and such episodes have occurred at the same time as major societal changes. Particularly interesting events include the decline of the Old Kingdom of Egypt and the Akkadian Empire of Mesopotamia and the disappearance of the Harappan civilization in the western Indian subcontinent at 2200 BC and the Anasazi movements of the 12th century. One problem confronting our ability to confidently predict future hydroclimatology or unravel the history of past drought episodes is our limited understanding of how the Pacific Ocean and the ENSO system responds to climate warming and cooling. New and previously published paleohydrological records from California, India and Hawaii provide a coherent picture of Pacific Ocean response to recent and more distant warming episodes – that pattern is a cooling of the eastern equatorial Pacific similar to a persistent La Niña.
Robert Sampson, chairman of the Department of Sociology and Henry Ford II Professor of the Social Sciences at Harvard University, will speak as part of the Late Lessons from Early History lecture series.