Global warming is a familiar term in today’s vocabulary — used to both champion the drive to clean up our environment and cast blame for poor weather patterns. However, do we really understand the science behind global warming and what its impact really means?
On Thursday, June 19, at 7:00 p.m., at the University of Delaware’s College of Marine Studies in Lewes, Ferris Webster, professor of oceanography, will discuss “The Science of Global Warming.” Webster’s presentation is part of the Ocean Currents Lecture Series, which is held monthly at the Lewes campus through September.
Webster will begin his talk by describing the importance of the greenhouse effect for life on Earth. The greenhouse effect refers to the fact that the surface of the Earth is warmer than it would be in the absence of an atmosphere because the atmosphere retains heat.
“Earth’s atmosphere maintains the temperature of the Earth and allows our planet to sustain life — the only such planet in our solar system,” says Webster. “Mars has hardly any atmosphere and is nearly always frozen, with an average temperature of about minus 85°C. On Earth’s other side is Venus, with an atmosphere that at the surface can crush a person. Venus is like a furnace, with a temperature of about 450°C.”
Webster notes that the Earth is warming, with an average increase of 0.6ºC over the last century. However, he adds that it is important to know if this warming is natural or whether it is due to human activity.
The history of Earth’s climate shows that variability is normal. Natural factors include variations in Earth’s orbit and in solar emissions. Human influences, which increase some gases in the atmosphere, can enhance the greenhouse effect and thereby cause warming. On the other hand, cooling can occur due to human-generated aerosols in the atmosphere.
Research is currently being conducted in an effort to distinguish between natural warming and human-generated warming. Studies of global climate models, records of past climate change, and examination of regional patterns of warming are all being used to help identify these two effects.
In his presentation, Webster also will discuss some of the controversies surrounding global warming. For example, the Intergovernmental Panel on Climate Change (IPCC), which was established by the World Meteorological Organization and the United Nations Environment Network, concludes that most of the observed warming over the last 50 years is likely due to human activities. Contrarians, however, have objected to the IPCC consensus. They add that even if moderate warming were to materialize, its benefits would be largely benign.
“Many uncertainties about global warming remain,” Webster concludes. “We are carrying out a risky, uncontrolled experiment with Earth’s climate. We need only look at our neighboring planets to realize that the climate system on Earth is unique, and it must be preserved.”
A member of UD’s faculty since 1983, Webster is professor of oceanography and director of the Oceanography Program at the College of Marine Studies. He earned his doctorate in geophysics in 1961 from the Massachusetts Institute of Technology. Since 1994, he has served as chairman of the Panel on World Data Centers of the International Council for Science.
The lecture will begin at 7:00 p.m. in Room 104, Cannon Laboratory, at the Hugh R. Sharp Campus, 700 Pilottown Road, Lewes. The hour-long talk will be followed by light refreshments.
While the lecture is free and open to the public, seating is limited and reservations are required. To reserve your seat, please contact the college at (302) 645-4279.