Our precarious planet

摘要

Yesterday I attended a lecture at the Institute of the Americas on the UCSD campus. The title of the talk was "Global Climate Change and the Making of a Report to the President of the United States." The speaker was Dr. Ralph Cicerone, Professor of Earth Science as well as Chancellor of the University of California at Irvine, and an expert on the greenhouse effect. He began his talk by defining the greenhouse effect, which results from an interaction of gaseous constituents in the Earth's atmosphere with radiation from the sun. While Mars, for example, lacks a gaseous atmosphere and is a cold planet, both Earth and Venus are warmed by the heat absorptive characteristics of their atmospheres.