Biosketch

Dr. Severinghaus is Professor of Geosciences at the Scripps Institution of Oceanography, which is affiliated with the University of California, San Diego. He received his PhD from Columbia University’s Lamont Doherty Earth Observatory in 1995, in isotope geochemistry. He also received a master’s degree in geological sciences from the University of California, Santa Barbara, and a bachelor’s degree from Oberlin College. He is an isotope geochemist working on gases trapped in ice cores, to reconstruct past variations in atmospheric composition and climate. His research often takes him to Antarctica and Greenland, and he is a member of the International Partnerships for Ice Core Sciences (IPICS) Steering Committee, and is co-chair of the “Oldest Ice” project that aims to extend the ice core record of atmospheric carbon dioxide and climate back to 1.5 million years ago. Dr. Severinghaus is the author of 115 refereed publications, and is a member of the National Academy of Sciences. He was the 2011 Claire C. Patterson Medalist for environmental geochemistry, and is a Fellow of the American Association for the Advancement of Science, and a Fellow of the American Geophysical Union. He lives in Solana Beach, CA, with his wife and 2 children.

Research Interests

Understanding the Earth's climate system is a grand challenge of our time because of the urgent need to predict the impacts of human-induced warming over the next century. Dr. Severinghaus uses the record of past climate to probe how Earth responded to past external heating, to illuminate the internal mechanisms of the climate system. His main interest lies in gases trapped in air bubbles in glacial ice from Antarctica and Greenland, which reveal how past atmospheric composition amplified natural warming episodes. His main activities have included development of new proxy indicators of air and ocean temperature, using noble gases and their isotopes from air bubbles in ice cores. These have shown that climate can change abruptly, on timescales of decades or less, with Arctic temperatures rising as much as 10 degrees C. He has also shown, using isotopes of atmospheric oxygen from ice cores, that tropical rainfall belts can shift abruptly southward in response to strong ice melting events in the North Atlantic region. These findings indicate that low-latitude rainfall is sensitive to the inter-hemispheric temperature difference, and that human activities that inadvertently change this difference may cause large-scale tropical drought in regions where billions of people make their livelihood on rain-fed agriculture.

Membership Type

Member

Election Year

2015

Primary Section

Section 15: Geology