The global impact and social consequences of El Nino -- an intermittent climate phenomenon characterized by abrupt changes in earth climate and warming of sea temperatures -- will be explored in a series of four lectures being presented under the aegis of the Center for the Study of Global Change.
Speakers for the series will discuss the scientific basis of the El Nino-Southern Oscillation phenomenon, the record of its occurrences from archaeological studies in Peru, and the climatologic and medical consequences of the phenomenon.
The El Nino effect occurs every four or five years and persists for about one year. It was first discovered in the 1950s by noting sea surface temperature changes along the coast of Peru, which occur typically just a few weeks before Christmas (El Nino is the Spanish name for "The Child," referring to the Christ child). Warming of the sea surface causes fish to die and production of plankton and other marine organisms to shut down when the warm upper layer stops the mixing of nutrients from lower layers. The Southern Oscillation is a change in atmospheric pressure along the equator that is now known to be linked to the El Nino effect. These atmospheric changes are accompanied by changes in ocean current and wind, which influence climate all around the world.
"El Nino can devastate the coastal ecosystem of Ecuador and Peru, interrupt the Indian monsoon and cause large swings in the flow of the Nile River," explains Jeffrey Park, associate professor in geology and geophysics, who will be the first speaker in the series.
All of the talks will be held at 2 p.m. in Rm. 102 of the Kline Geology Laboratory, 210 Whitney Ave. They are free and open to the public. The following is a schedule of talks:
Sept. 30 -- "Do Interannual Temperature 'Events' Herald Shifts in Northern Hemisphere Warming?" by Professor Park.
Oct. 14 -- "The Prehistory of El Nino: A Geoarchaeological Perspective" by D. Sandweiss, department of anthropology, University of Maine.
Oct. 21 -- "Why the Coasts of Ecuador and Peru Are Deserts Today" by G. Philander, department of geological and geophysical sciences, Princeton University.
Nov. 11 -- "Tracking the Origin of Cholera: The Role of Global Climate and Ocean Circulation in the Epidemiology of Water-borne Disease" by R. R. Colwell, University of Maryland Biotechnology Institute.