Chair’s Message

Department Chairman and Professor Jay Ague

Welcome to the Department of Earth and Planetary Sciences at Yale University.

As you browse through our website you’ll discover that our field is one of the truly cross-disciplinary areas that brings together physics, chemistry, biology, math and geology in order to understand the planet on which we live.  Our faculty, research scientists and students tackle issues of vital importance to society, including earthquakes, volcanic hazards, hurricanes, climate change, evolution and the fossil record, atmospheric carbon remediation, and the sustainability of natural resources.  But we also explore fundamental questions such as the origin and evolution of the solar system and planets, the origin and rise of life, and the cause for climate variability over billions of years of Earth’s history.  This breadth leads to collaborative interactions with many other departments on campus, such as Astronomy, Chemistry, Ecology & Evolutionary Biology, Economics, Engineering, Mathematics and Physics.

Our department is also one of the oldest natural science departments in the country. Numerous “firsts” include Benjamin Silliman’s analysis of the Weston meteorite in 1807, the first documented fall of a meteorite in the Americas; James Dwight Dana’s System of Mineralogy, still in use today; the appointment of Othniel C. Marsh, the first Professor of Paleontology in the United States; Bertram B. Boltwood’s invention of uranium-lead radiometric dating to give the first reasonable age of rocks (and the Earth); Elias Loomis’ synoptic weather maps, the first to depict high and low pressure air masses and enable forecasting (not to mention his use of chickens to estimate tornado wind speeds); Joseph Barrell’s groundbreaking concepts of the lithosphere, asthenosphere, and isostatic adjustment. And Yale was the home of Josiah Willard Gibbs, considered the father of classical thermodynamics, which is central to the study of phase transitions in all matter, from minerals to water. 

Our undergraduate students have diverse opportunities to learn, mix and apply the various fields of Earth science to fundamental and contemporary issues. Undergraduate B.A. or B.S. degrees include four tracks in Earth and climate sciences: (1) Atmosphere, ocean, and climate; (2) Environmental and energy geoscience; (3) Paleontology and geobiology; and (4) Solid Earth and planets. Graduate students pursue Ph.D. research in any area of specialization represented by the faculty. Moreover, interdisciplinary study among research groups as well as with other departments at Yale is common and encouraged. The department is also the home of the popular Energy Studies Program ( with students participating from across the university.

Undergraduate and graduate students from our department have gone on to careers in industry, government, and academia. In academia, alumni are represented on the faculty of numerous universities and liberal arts colleges including Boston University, Brown, Cornell, Harvard, Johns Hopkins, MIT, Penn State, Smith, Stanford, the University of Southern California, UCSD (Scripps Inst.), the Universities of Hawaii, Michigan, Rochester, Wisconsin, as well as Washington & Lee and Virginia Tech. In other fields of endeavor, alumni have forged careers at the American Museum of Natural History, the Gemological Institute of America, the Department of Energy (DOE), the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), the Smithsonian Institution, the U.S. Army Corps of Engineers, the U.S. Geological Survey, and numerous environmental consulting, natural resources, and energy companies throughout the world.

Today, it is clear that our future depends on environmental stewardship and the sustainable use of Earth’s resources. This is especially true in dealing with the coupled problems of energy consumption and climate change.   These challenges become more formidable each day as Earth’s population grows, placing increasing demands on supplies of water, minerals, and energy, as well as the resulting impact on our habitable environment. Ultimately, progress in these critical issues, at both the national and international levels, requires the integrated efforts of scientists and policy makers.  Meeting these challenges, and providing the rigorous scientific framework in which to face them, is one of our primary goals.

On that note, welcome!  Please enjoy our website and feel free to contact us with questions about any of our programs (


Dave Bercovici