Research
Research Interests and Philosophy
My research interests largely revolve around climate, cryosphere, and landscape systems and the interactions and evolution of those systems through space and time. The approaches and techniques I employ are just as varied as the questions I pursue, from sediment cores to cosmogenic nuclide exposure dating, to numerical models and GIS analyses. I am especially excited about developing and utilizing synergistic collaborations between people and techniques to investigate and explore past and present climate-cryosphere-landscape interactions to better understand our future.
Throughout these research efforts, I encourage and support involvement from a diversity of collaborators and, importantly, from students themselves. If you are interested in joining ongoing research, collaborating on potential research, or developing new research avenues, I encourage you to reach out to me!
Current Research Activities
New England Climate Reconstruction
While New England hosts a detailed record of ice sheet retreat following the last ice age, much less is known about the climate following deglaciation. Along with colleagues at PSU, and the Forest Service, we have collected pilot cores from an isolated lake basin in northern New Hampshire to reconstruct both environmental and climate histories from the watershed. PSU student Jennifer Limoges is working with me to analyze biomarkers from the sediment cores to reconstruct temperature and precipitation trends following deglaciation up through the Holocene. This is the initial step in a larger project aimed at determining the influence of local climate on ice margin fluctuations during retreat; a coupling that is highly relevant to modern day shrinking ice sheets.
Collection of sediment cores from Cone Pond for environmental and climate reconstructions
Students and community members participating in a tree coring workshop; a technique we use to identify past fire events.
New England Wildfire Histories
New England has a unique history with fire but several questions remain outstanding with respect to fire, its history, its association with humans, and its role in the evolution of northern forests. Working with dendrochronologists from NOAA and the partners in USFS, we utilize multiple techniques to reconstruct fire histories from the region, such as tree ring and tree scar surveys, GIS analyses, and charcoal records. At PSU I am focused on reconstructing fire frequency and magnitude using charcoal preserved in sediment crore extracted from lakes and bogs. The goal of this work is to provide context for modern fire regimes and guide fire management into the future.
Recent winters in New Hampshire have been warming and bringing erratic temperature and precipitation swings. This has been impacting lake ice cover, to the point where lakes with traditionally consistent and thick ice cover are showing later ice-in and earlier ice-out dates. This is threatening wintertime ice recreation, in some cases even impacting long-standing ice fishing events. Additionally, changes to ice cover and ice thickness through the winter season can have large, and uncertain impacts on the overall physical and biological health of the lakes.
The goal of this project is to develop a citizen-driven method of recording lake ice and snow cover thickness throughout the winter. We are interested in how lake snow and ice cover is changing and how it might potentially impact the physical and biological characteristics of our lakes.
A lakeside kiosk to engage lake users as citizen scientists to gather data on lake ice and snow thicknesses across the region.
Erratic boulders like this one dropped by the retreating ice sheet can constrain the timing of deglaciation at their location.
Tracing Ice Sheet Retreat with Exposure Dating
As modern ice sheets continue to retreat under a warming climate, future projections in part rely on our understanding of the impact of local, ice-marginal conditions vs. upstream dynamics and hemispheric forcings. The retreat of the Laurentide Ice Sheet (LIS) across New England following the last glacial maximum (~20 ka) provides a potentially useful analog. While LIS deglaciation across the region is broadly constrained, we seek to add important spatial temporal constraints on ice sheet retreat using cosmogenic nuclide exposure dating of erratic boulders and glacial landforms in central NH.
