I have spent most of my career investigating climate history of the Great Plains and northern Rocky Mountain region, including the development of a modern data set of diatoms and associated water-chemistry variables to use in core interpretation and the analysis of a suite of cores from east to west across the region. These analyses have been instrumental in documenting that sustained drought has been more common in the recent past than in the 20th century.

We are continuing to work on lakes in the North American continental interior to develop high-resolution (decadal) records of climate history. Our interests include evaluating how the magnitude and frequency of drought changes through time, spatial patterns of climate variation across the mid-continent, and the relative importance of varied climate forcings at different temporal scales.

In addition to reconstructing climate history itself, we are evaluating the role of catchment processes and biotic interactions in affecting ecosystem structure and function.