Greg Hakim is the Chair of Atmospheric Sciences, and works to understand what the climate is doing now and will do in the future by reconstructing what it did in the past. To do this, he combs through the historical record for those sparse and noisy proxies of the state of the climate at different times. With those proxies, he is able to get view into the past far beyond the instrumented record, which goes back only about 150 years. Additionally, he also builds models to describe dynamic weather events, such as cyclones and hurricanes. With James Holton, he is the author of An Introduction to Dynamic Meteorology, now in its fifth edition.