USAP-DC

This award supports a project to perform continuous microparticle concentration and size distribution measurements (using coulter counter and state-of-the-art laser detector methods), analysis of biologically relevant trace elements associated with microparticles (Fe, Zn, Co, Cd, Cu), and tephra measurements on the WAIS Divide ice core. This initial three-year project includes analysis of ice core spanning the instrumental (~1850-present) to mid- Holocene (~5000 years BP) period, with sample resolution ranging from subannual to decadal. The intellectual merit of the project is that it will help in establishing the relationships among climate, atmospheric aerosols from terrestrial and volcanic sources, ocean biogeochemistry, and greenhouse gases on several timescales which remain a fundamental problem in paleoclimatology. The atmospheric mineral dust plays an important but uncertain role in direct radiative forcing, and the microparticle datasets produced in this project will allow us to examine changes in South Pacific aerosol loading, atmospheric dynamics, and dust source area climate. The phasing of changes in aerosol properties within Antarctica, throughout the Southern Hemisphere, and globally is unclear, largely due to the limited number of annually dated records extending into the glacial period and the lack of a
tephra framework to correlate records. The broader impacts of the proposed research are an interdisciplinary approach to climate science problems, and will contribute to several WAIS Divide science themes as well as the broader paleoclimate and oceanographic communities. Because the research topics have a large and direct societal relevance, the project will form a centerpiece of various outreach efforts at UMaine and NMT including institution websites, public speaking, local K-12 school interaction, media interviews and news releases, and popular literature. At least one PhD student and one MS student will be directly supported by this project, including fieldwork, core processing, laboratory analysis, and data interpretation/publication. We expect that one graduate student per year will apply for a core handler/assistant driller position through the WAIS Divide Science Coordination Office, and that undergraduate student involvement will result in several Capstone experience projects (a UMaine graduation requirement). Data and ideas generated from the project will be integrated into undergraduate and graduate course curricula at both institutions.

Person	Role
Koffman, Bess	Investigator
Kreutz, Karl	Co-Investigator
Breton, Daniel	Co-Investigator
Dunbar, Nelia	Investigator
Hamilton, Gordon S.	Co-Investigator

Antarctic Glaciology	Award # 0636767
Antarctic Glaciology	Award # 0636740

NSIDC-0506_1
dunbar_0636767
NSIDC-0620_1
kreutz_0636740
USAP-0636740
NSIDC-0616_1
NSIDC-0499_1

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	WAIS Divide WDC06A Discrete ICP-MS Chemistry	None	exist
USAP-DC	Snowpit evidence of the 2011 Puyehue-Cordon Caulle (Chile) eruption in West Antarctica	None	exist
USAP-DC	Microparticle, Conductivity, and Density Measurements from the WAIS Divide Deep Ice Core, Antarctica	None	exist
USAP-DC	WAIS Divide Snowpit Chemical and Isotope Measurements, Antarctica	None	exist
USAP-DC	WAIS Divide Microparticle Concentration and Size Distribution, 0-2400 ka	None	exist
USAP-DC	Snowpit Chemistry - Methods Comparison, WAIS Divide, Antarctica	None	exist

1. Koffman, B.G., Kreutz, K.J., Kurbatov, A.V. and Dunbar, N.W. 2013. Impact of known local and tropical volcanic eruptions of the past millennium on the WAIS Divide microparticle record. Geophysical Research Letters, 40(17), p. 4712-4716. doi: 10.1002/grl.50822. (doi:10.1002/grl.50822)
2. Lee, M. J., Kyle, P. R., Iverson, N. A., Lee, J. I., & Han, Y. (2019). Rittmann volcano, Antarctica as the source of a widespread 1252 ± 2 CE tephra layer in Antarctica ice. Earth and Planetary Science Letters, 521, 169–176. (doi:10.1016/j.epsl.2019.06.002)
3. Koffman, B. G., Dowd, E. G., Osterberg, E. C., Ferris, D. G., Hartman, L. H., Wheatley, S. D., … Yates, M. (2017). Rapid transport of ash and sulfate from the 2011 Puyehue-Cordón Caulle (Chile) eruption to West Antarctica. Journal of Geophysical Research: Atmospheres, 122(16), 8908–8920. (doi:10.1002/2017jd026893)