His research focuses on climate change, its causes and its impact on the environment and society. He works on climate variability and environmental change using observational and other records in North America, Eurasia and Africa. He is the author of over 160 scientific and popular press pieces and an award winning book on biogeography. His recent coastal and marine research focusses on estuaries and marshes and their response to climate change, sea level change and human disturbance. He has also worked on seismic displacements of marshes. Glen has worked on marsh and mangrove systems in California, Hawaii and Mexico. He is also interested in scientific communication and has published Op/Eds in the Los Angeles Times, San Francisco Chronicle and Sacramento Bee. He speaks widely to the public and policy makers and has provided presentations and testimony to a number of California state agencies and the US Senate Appropriations Committee. Glen MacDonald is a Member of the National Academy of Sciences, a Fellow of the American Academy of Arts and Sciences, a Fellow of the American Geophysical Union, a Fellow of the American Association for the Advancement of Science, a Guggenheim Fellow, a Rockefeller Bellagio Resident and a Past President of the American Association of Geographers. He has received the James J. Parsons Distinguished Career Award and the Henry C. Cowles Award for Excellence in Publication from the American Association of Geographers, the University of Helsinki Medal, a Visiting Fellowship and Life Membership at Clare Hall Cambridge, and a Visiting Fellowship at St. Catherine’s College, Oxford. He has also won distinguished teaching awards at McMaster University and UCLA.