My research interests to date have centered upon investigating the extent and timing of changes in glacial systems as a means of advancing an understanding of paleoclimatic events. The methods I use include field mapping based on geomorphology, sedimentology and stratigraphy and applications of surface exposure dating.

My current research at L-DEO (since 6/2004) focuses on surface exposure dating of glacial moraines in the Scoresby Sund region of East Greenland. This project is being carried out with Drs. GH Denton, WS Broecker, JM Schaefer, BL Hall and TV Lowell., The goal of this research is to investigate an inconsistency between two important paleoclimatic archives that register abrupt climatic changes during last glacial period and glacial-interglacial transition. Bore-hole paleothermometry and isotopic fractionation of gasses in Greenland ice cores, such as GISP2, indicate a 16+/-3°C temperature difference relative to present during the Younger Dryas (~12.8-11.5 kyr). The equilibrium line altitude (ELA) depressions of mid-to-high-latitude glaciers do not show such a severe climatic change as the ice cores, but instead suggest a temperature decrease of 2-4°C relative to present during the Younger Dryas. These differences in temperature between the ice-core and mountain glacier records are too large to be explained by method-specific uncertainties and may be due to an important natural phenomenon that is not yet included in hypotheses of past abrupt climatic changes., Glacial moraines in the Scoresby Sund region are located near Greenland ice core sites and should provide a side-by-side comparison with the ice-core paleotemperature records. I will apply the surface exposure dating method to determine an age of the moraines. These results, coupled with ELA depression estimates from the moraines, will allow a calculation of mean summer temperature at the time the glacier existed.

As a University Postdoctoral Fellow at the Byrd Polar Research Center of The Ohio State University (5/2003-5/2004), I applied the surface exposure method to date moraine systems in the Peruvian Andes near the sites of ice cores recovered by Dr. LG Thompson and the Ice-Core Paleoclimatology Research Group. I sampled boulders on moraines in the Cordillera Vilcanota and near the Nevado Coropuna and am preparing samples for the measurement of 10Be, 26Al and 36Cl. Dates of glacial moraines from this tropical region should provide not only a complement to ice-core records from Dr. Thompson's research, but also an interesting comparison with paleoclimatic records from high latitudes.

Some of my projects include:

• Extent and timing of late-glacial advances in the Scoresby Sund region, East Greenland
• Surface exposure dating of glacial moraines in the Peruvian Andes; in cooperation with Dr. LG Thompson, The Ohio State University