The story notes the very reasons we had him on the show:
Alley is one of the world's leading climate researchers and also works with the Earth and Environmental Systems Institute at Penn State. He is one of several earth scientists from Penn State who contributed to the United Nations Intergovernmental Panel on Climate Change, which shared the 2007 Nobel Prize with Al Gore. His current research focuses on glaciology, ice sheet stability and paleoclimates from ice cores. He has based his work on a meticulous study of ice cores from Greenland and West Antarctica. Alley's work has been lauded for contributing to the understanding of climate science not only through superlative research, but also through his ability to inform nonscientists.He is also a go-to guy for people like Gore and noted science journalist and blogger Andy Revkin at DotEarth.