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
- Danielle LeBlanc: 3 Myr of Laurentide Ice Sheethistory inferred from cosmogenic nuclides in ice-rafted debris (Ph.D.)
Recent M.S. Alumni and Projects
- Drew Gorin: Recent tropical Andes glacier retreatunprecedented in the Holocene (M.S., 2021)
- Celeste Gambino: A uranium-lead chronology of speleothem deposition in the Canadian Arctic (M.S., 2018)
- Chris Halsted: Determining the Timing and Rate of Laurentide Ice Sheet Thinning During the Last Deglaciation in New England with 10Be Dipsticks (M.S., 2018)
- Cole Vickers: Tropical Andean and African glacier extent through the Holocene assessed with proglacial in situ 14C and 10Be measurements (M.S., 2018)
Selected Recent Publications (*BC student co-authors)
- Biller-Celander, N., Shakun, J. D., McGee, D. M., Wong, C. I., Reyes, A. B.,Hardt, B., Tal, I., Ford, D., and Lauriol, B. (2021). Increasing Pleistocenepermafrost persistence and carbon cycle conundrums inferred from Canadianspeleothems. Science Advances, 7, doi:10.1126/sciadv.abe5799.
- Vickers, A. C., Shakun, J. D., Goehring, B. M., *Gorin, A., Kelly, M. A., Jackson,M. S., Doughty, A., and Russell, J. (2021). Similar Holocene glaciation historiesin tropical South America and Africa. Geology, 49, 140-144.
- Koester, A. J., Shakun, J. D., Bierman, P. R., Davis, P. T., Corbett, L. B.,Goehring, B. M., *Vickers, A. C., and Zimmerman, S. R. (2020). Laurentide IceSheet thinning and erosive regimes at Mount Washington, New Hampshire,inferred from multiple cosmogenic nuclides, GSA Special Paper 548,doi/10.1130/2020.2548(15)..
- Shakun, J. D., Corbett, L. B., Bierman, P. R., Underwood, K., Rizzo, D., Zimmerman, S. R., Caffee, M. W., Naish, T., Golledge, N, and Hay, C. (2018). Minimal East Antarctic Ice Sheet retreat onto land during the past eight million years. Nature, 558, https://doi.org/10.1038/s41586-018-0155-6.