Congressional Briefing Series on Science and Impacts: South American Glacier Loss

October, 20, 2006

The tropical Andes is one of the regions of the globe where recent climate change is most evident.  Andean glaciers are receding rapidly, with potentially severe consequences for the availability of water for drinking, irrigation, mining, and hydropower. Climate models predict an additional warming of 7-9 °F in the region if atmospheric carbon dioxide doubles from pre-industrial levels by the end of this century. Some glaciers are already destined to disappear completely; for many more, the threshold for disappearance will be reached within the next 10 to 20 years unless conditions change quickly.

Rapid glacier retreat places in doubt the sustainability of current patterns of water use and ultimately the viability of the economies and ecologies of the Andes.  The changes induced by tropical glacier retreat constitute an early case of the need for adaptation and therefore an example of the impacts caused by climate change.


Two leading experts, Dr. Mathias Vuille and Mr. Walter Vergara, will present the state of knowledge regarding the science and impacts of mountain glacier loss in tropical South America, with special focus on the Andes Mountains of Peru, where glacier retreat is particularly advanced.


Mathias Vuille, Ph.D.
University of Massachusetts, Amherst
Dr. Vuille Research Associate Professor at the Climate System Research Center, Department of Geosciences, University of Massachusetts Amherst.  His research interests are in tropical climatology and paleoclimatology, with particular interest in linking observed modern climate dynamics to paleoclimatic interpretation of proxy data.  He is the lead investigator on a research project funded by the National Science Foundation to investigate the "Impact and consequences of predicted climate change on Andean glaciation and runoff."  He has published more than 40 peer-reviewed papers on paleoclimate and glaciology.  Dr. Vuille earned his M.S. and Ph.D. degrees from University of Bern, Switzerland.

Walter Vergara
The World Bank
Mr. Vergara is Lead Engineer in the Environmentally and Socially Sustainable Development Department of the World Bank’s Latin America and Caribbean Regional Office.  Mr. Vergara works on climate change issues and has participated in development of the carbon finance portfolio in the region, as well as initiatives on adaptation to climate change, transport and climate change, air quality, application of the Clean Development Mechanism (CDM) to wastewater, solid waste management, and renewable energy.  He is the author of four books and numerous technical articles, and currently manages an extensive portfolio of climate initiatives in the region.  Mr. Vergara is a chemical engineer and graduate of Cornell University in Ithaca, New York, and the Universidad de Colombia in Bogotá.

Jay Gulledge, Ph.D.
Pew Center on Global Climate Change
Dr. Gulledge is Senior Research Fellow for Science and Impacts at the Pew Center on Global Climate Change. He serves as the Center’s in-house scientist and coordinates its work to communicate the state of knowledge on the science and environmental impacts of global climate change to policy-makers and the public. He is also an adjunct Associate Professor at the University of Wyoming, home to his academic research on the carbon cycle. He has published more than a dozen refereed journal articles on microbial ecology and biogeochemical cycling of atmospheric greenhouse gases, and serves as an associate editor of Ecological Applications, a peer-reviewed journal published by the Ecological Society of America. Dr. Gulledge earned a PhD in Ecosystem Sciences from the University of Alaska Fairbanks.