I am a paleoclimatologist who uses the geologic record to decipher the patterns and mechanisms of past changes in climate and ice sheets on decade to million year time scales. This research is guided by a series of overarching questions - how sensitive is the climate to external forcings, how are various regions and components of the climate system linked, and how well do models simulate the past? My research group applies various tools to address these questions, including developing geochemical records from several paleo-archives (glacier, marine, and cave deposits), and mining the growing body of paleoclimate datasets to search for large-scale patterns. These approaches can entail work behind the computer, in various collaborators' labs, and in the field from places as far off as the Arctic or as close as New England. I'm particularly motivated by paleoclimate problems that have clear relevance to today.
Current Graduate Students and Projects
- Calen Rubin: Reconstructing North American ice sheet history from glacial dipsticks, marine sediments, and cave deposits (Ph.D.)
- Lauren Gustafson: Mapping the Laurentide Ice Sheet meltwater plume in the Gulf of Mexico during the last deglaciation (M.S.)
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Recent M.S. Alumni and Projects
- Danielle LeBlanc: 3 Myr of Laurentide Ice Sheethistory inferred from cosmogenic nuclides in ice-rafted debris (Ph.D.)
- Drew Gorin: Recent tropical Andes glacier retreatunprecedented in the HoloceneÌý(M.S., 2021)
- Celeste Gambino:ÌýA uranium-lead chronology of speleothem deposition in the Canadian Arctic (M.S., 2018)
- Chris Halsted:ÌýDetermining the Timing and Rate of Laurentide Ice Sheet Thinning During the Last Deglaciation in New England withÌý10Be DipsticksÌý(M.S., 2018)
- Cole Vickers:ÌýTropical Andean and African glacier extent through the Holocene assessed with proglacialÌýin situÌý14C andÌý10Be measurements (M.S., 2018)
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Selected Recent Publications (*51²è¹Ý student co-authors)
- *Gorin, A. L., Shakun, J. D., Jones, A. G., Kennedy, T. M., Marcott, S. A., Goehring, B. M., Bromley, G. R., Jomelli, V., Mateo, E. I., Mark, B. G., Rodbell, D. T., Gilbert, A., and Caffee, M. W. (2024). Recent tropical Andean glacier retreat is unprecedented in the Holocene. Science, 385, 517-521.
- Batchelor, C., McGee, W. D., Shakun, J. D., Woodhead, J., Jost, A., Arnold, S., Horne, G., Kinsley, C., and Puricelli, M. (2024). Insights into changing interglacial conditions in subarctic Canada from MIS 11 through MIS 5e from seasonally-resolved speleothem records. Geophysical Research Letters, https://doi.org/10.1029/2024GL108459.
- Clark, P. U., Shakun, J. D., Rosenthal, Y., Kohler, P., and Bartlein, P. J. Global and regional temperature change over the last 4.5 Myr. (2024). Science, 383, 884-890.
- Jones, A. J., Marcott, S. A., *Gorin, A. L., Kennedy, T. M., Shakun, J. D., Goehring, B. M., Menounos, B., Clark, D. H., Romero, M. and Caffee, M. W. Four North American glaciers advanced past their modern positions thousands of years apart in the Holocene. (2023). The Cryosphere, doi:10.5194/tc-17-5459-2023.
- Halsted, C. T., Bierman, P.R., Shakun, J. D., Davis, P. T., Corbett, L. B., Caffee, M.W., Ridge. J. C., and Drebber, J. A critical re-analysis of constraints on the timing and rate of Laurentide Ice Sheet recession in the northeastern United States. (2023). Journal of Quaternary Science, 1-16, doi:10.1002/jqs.3563.
- *LeBlanc, D. E., Shakun, J. D., Corbett, L. B., Bierman, P. R., Caffee, M. W., and Hidy, A. J. (2023). Laurentide Ice Sheet persistence during Pleistocene interglacials. Geology, 51, 496-499, https://doi.org/10.1130/G50820.1.
- *Halsted, C. T., Bierman, P. R., Shakun, J. D., Davis. P. T., Corbett, L. B., Caffee, M. W., Koester, A. J., Hodgdon, T., and Licciardi, J. (2023). Rapid southeastern Laurentide Ice Sheet thinning during the last deglaciation revealed by elevation profiles of in situ cosmogenic 10Be. Geological Society of America Bulletin, 135, 2075-2087, https://doi.org/10.1130/B36463.1.