This afternoon Dr. Mimi Katz gave a seminar for the RPI Physics department on climate science. The aim was to correct the impression left by Dr. Giaever’s seminar, reviewed earlier on this blog. In a soft-spoken introduction Dr. Bruce Watson outlined four areas of research in earth and environmental science that have impact on climate science: direct measurements of trends, external forces affecting climate, long-term records of past events, and computational modeling. He emphasized that these different approaches all converged on the same basic conclusion, that the earth is growing warmer and that this is due to human activity. Dr. Katz then went into the details, providing independent evidence from a variety of investigations, on the trends in methane and CO2 in the atmosphere, direct measurements of temperature from upwards of 39,000 weather stations worldwide, measurements of greenhouse gases and temperature derived from ice cores, ocean science and biology including the opening of the Northwest Passage in 2010, rises in sea level, the migration of birds into ever more northerly zones, and much more, all of which are consistent with global warming and counter to the expected cooling that would arise without anthropogenic warming. She discussed modeling of the atmospheric temperature, which can describe recent data, and which under various assumptions predicts modest to alarming future temperature increases. It was a convincing, if low-key presentation. A key point was the graph of global temperature data, which shows a steady upward trend over the last century. She pointed out that the myth of recent cooling is a case of cherry picking of a set of recent data points that fall within the expected scatter as shown by the data from earlier years.
It was a well attended seminar, and once again there was lively participation by the audience during the question period after the seminar.