I was born and raised in Florida, and I trained as a marine scientist. As a young assistant professor at the University of New Hampshire, I met and came to know Paul Mayewski, a young glaciologist. In the early 1980s Mayewski was taking a group of students to Canada to study glaciers, and each student was required to do a project. I was recruited to assist a student who was interested in the chemistry of the ice.
The results of her work were quite interesting, and Paul and I decided to continue our collaboration. The following year Paul invited me to join his National Science Foundation-funded research team in Antarctica. Having never ventured to a polar region prior to this, but being of an adventurous mind, I said "Yes."
That was 20 years ago. As they say, "The rest is history." Over this 20-year period, I've spent three field seasons (from a few weeks to several months in length) in Greenland, one in Iceland and 12 in the Antarctic. Science sometimes takes serendipitous paths!
Why did I continue this work? First, the stark beauty of the polar regions is beyond belief. The McMurdo Dry Valleys region in Antarctica where Paul took me and where I work today is simply one of the most unusual and most beautiful landscapes on the planet. It is a composite of bedrock, soils, ice-covered lakes, ephemeral streams, and alpine glaciers. Here, as part of the McMurdo Dry Valleys Long-Term Ecological Research program, a group of diverse scientists (ecologists, hydrologists, limnologists, ecological modelers) investigates the structure and function of the very robust ecosystem that occurs here. Many of the characteristics of this "polar desert" ecosystem are potentially analogous to the ecosystem that could have existed on early Mars.
Second, I keep returning to the polar regions because of the interesting scientific questions that can be answered only by working there. Richard Alley, a noted glaciologist at Pennsylvania State University, University Park, has argued quite eloquently that the polar regions, particularly the Arctic, control global climate change. A major thrust of polar research over the past decade has been to unravel the history of climate variation of our planet over the last hundreds of thousands of years.
The major tool for accomplishing this has been the production of very detailed ice-core records. These cores, from both Greenland and Antarctica, have yielded important new insights into climatic dynamics and changes in atmospheric chemistry and have revealed that rapid climate change events (changes of many degrees of temperature in decadal time frames) were quite frequent during past glacial periods. These polar ice-core "histories" have been coupled with ice-core records from lower latitudes, marine sediment cores, and other proxy climatic records to develop a global picture of climate change over the past half-million years or so. As Alley has pointed out, much of the global climatic response is governed by conditions in the high northern latitudes.
In my work, I have used various geochemical approaches to solve biogeochemical, hydrological, and paleoclimatic problems. For example, our group has been using both isotopic and elemental analyses to evaluate the climatic histories of the ice-covered lakes in the McMurdo Dry Valleys. With the help of Bob Poreda of the University of Rochester in New York and Shaun Frape of the University of Waterloo in Ontario, we have used helium and chloride isotopic variations to ascertain the age of the lakes and the time when the ice covers formed. In many cases, techniques that were originally used to investigate the world's oceans are now being used to study lake systems.
The polar regions have always attracted human interest in terms of exploration and conquest. Although the majority of these environments have now been explored, the polar latitudes contain scientific information relating to Earth's past climate that may provide important new insights into how our climate may change in the future. The polar regions have been called climatic amplifiers in that climate models generally predict amplified warming in the polar regions due to the increase of greenhouse gases in the atmosphere. Much important new scientific information will be gained from the study of polar regions by the next generation of polar scientists. This information is needed in order to develop better models of future climate change.