Presentation by Dr. Jeff Severinghaus, a climate science researcher from Scripps Institution of Oceanography. His team studies historic temperatures at ice core sites on the West Antarctic Ice Sheet and Greenland. Dr. Severinghaus’s current research interests center on using trapped bubbles of gases contained in ice cores to track changes in ancient climate Atmospheric air bubbles are trapped in glacial ice and provide a unique window on the past greenhouse gas composition and climate. These samples of our past have provided a cornucopia of information about natural climate change and how sensitive the Earth is to heat-trapping gases like CO2 and methane. This gives us confidence in making predictions that fossil fuel burning is now radically altering our children’s and grandchildren’s future. Professor Severinghaus will discuss how we know that current planetary heating is caused by humans and is not natural. He will also explain and expose a few myths. There will be time for questions from the audience.