Doctor of Philosophy in Earth System Science
The Earth, as a coupled system of atmosphere, ocean, land and cryosphere, has changed in our lifetime. The observed depletion of stratospheric ozone at high latitudes has been attributed directly to industrial use of halocarbons. Global warming is likely to result from increases in the atmospheric concentrations of greenhouse gases, such as carbon dioxide and methane, which are released by the use of fossil fuel and agricultural practices. These examples illustrate the ability of humans to alter the global environment on the time-scale of decades. Understanding the sensitivity of the Earth's climate system requires a broad base of scientific knowledge which includes detection, quantification, and prediction of the rates of change of chemical, physical and biological variables.
Our research interests focus attention on the atmosphere, ocean, cryosphere and terrestrial biosphere and on processes with the potential to change these systems over a human lifetime. An integrated approach is needed; our program requires a balance of field, laboratory and theoretical studies. Field and laboratory measurements define the rates and mechanisms of processes and exchanges within and between the atmosphere, ocean, cryosphere and terrestrial biosphere. They also provide information on the controls and feedbacks influencing these exchanges and permit identification of natural and anthropogenic processes.
Long-term observations of the Earth system, along with historical data sets and paleoclimate records, provide baseline data against which trends may be defined. The parallel development of predictive numerical models incorporating these processes is needed to interpret observations and to assess changes on regional and global scales.
The Department's doctoral program is aimed at training new research scientists in the field of Earth System Science. The graduate education provides a comprehensive curriculum, along with opportunities to conduct groundbreaking research. Our doctoral-level students are expected to become researchers with a global perspective and broad research skills as well as a high level of expertise in specific areas. Active programs of research are underway in atmospheric chemistry, biogeochemical cycles, and physical climate.