USAP-DC

Steig/1043092

This award supports a project to contribute one of the cornerstone analyses, stable isotopes of ice (Delta-D, Delta-O18) to the ongoing West Antarctic Ice Sheet Divide (WAIS) deep ice core. The WAIS Divide drilling project, a multi-institution project to obtain a continuous high resolution ice core record from central West Antarctica, reached a depth of 2560 m in early 2010; it is expected to take one or two more field seasons to reach the ice sheet bed (~3300 m), plus an additional four seasons for borehole logging and other activities including proposed replicate coring. The current proposal requests support to complete analyses on the WAIS Divide core to the base, where the age will be ~100,000 years or more. These analyses will form the basis for the investigation of a number of outstanding questions in climate and glaciology during the last glacial period, focused on the dynamics of the West Antarctic Ice Sheet and the relationship of West Antarctic climate to that of the Northern polar regions, the tropical Pacific, and the rest of the globe, on time scales ranging from years to tens of thousands of years. One new aspect of this work is the growing expertise at the University of Washington in climate modeling with isotope-tracer-enabled general circulation models, which will aid in the interpretation of the data. Another major new aspect is the completion and use of a high-resolution, semi-automated sampling system at the University of Colorado, which will permit the continuous analysis of isotope ratios via laser spectroscopy, at an effective resolution of ~2 cm or less, providing inter-annual time resolution for most of the core. Because continuous flow analyses of stable ice isotopes is a relatively new measurement, we will complement them with parallel measurements, every ~10-20 m, using traditional discrete sampling and analysis by mass spectrometry at the University of Washington. The intellectual merit and the overarching goal of the work are to see Inland WAIS become the reference ice isotope record for West Antarctica. The broader impacts of the work are that the data generated in this project pertain directly to policy-relevant and immediate questions of the stability of the West Antarctic ice sheet, and thus past and future changes in sea level, as well as the nature of climate change in the high southern latitudes. The project will also contribute to the development of modern isotope analysis techniques using laser spectroscopy, with applications well beyond ice cores. The project will involve a graduate student and postdoc who will work with both P.I.s, and spend time at both institutions. Data will be made available rapidly through the Antarctic Glaciological Data Center, for use by other researchers and the public.

Person	Role
White, James	Investigator
Vaughn, Bruce	Co-Investigator
Jones, Tyler R.	Investigator

Antarctic Earth Sciences	Award # 1043167
Antarctic Glaciology	Award # 1043167
Antarctic Earth Sciences	Award # 1043092
Antarctic Glaciology	Award # 1043092

NSF-ANT10-43167_1

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core	None	exist
USAP-DC	Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core	None	deprecated
USAP-DC	Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core	ASCII	exists
USAP-DC	Resampling of Deep Polar Ice Cores using Information Theory	None	exists
USAP-DC	Seasonal temperatures in West Antarctica during the Holocene	Excel	exists
USAP-DC	WAIS Divide Ice Core Discrete CH4 (80-3403m)	None	exists

1. Buizert, C., K.M. Cuffey, J.P. Severinghaus, D. Baggenstos, T.J. Fudge, E.J. Steig, T.A. Sowers, E.J. Brook, R.H. Rhodes, H. Cheng, L.R. Edwards, M. Sigl, J.R. McConnell, and K.C. Taylor (2015). The WAIS Divide deep ice core WD2014 chronology - Part 1: Methane synchronization (68-31 ka BP) and the gas age-ice age difference, Clim. Past, 11, 153-173, doi:10.5194/cp-11-153-2015. (doi:10.5194/cp-11-153-2015)
2. Cuffey, K.M., Clow, G.D., Steig, E.J., Buizert, C., Fudge, T.J., Koutnik, M., Waddington, E.D., Alley, R.A. and Severinghaus, J.P. 2016. Deglacial temperature history of West Antarctica, Proceedings of the National Academy of Sciences, 113(50), p. 14249-1425. doi: 10.1073/pnas.1609132113. (doi:10.1073/pnas.1609132113)
3. Buizert, C., Cuffey, K. M., Severinghaus, J. P., Baggenstos, D., Fudge, T. J., Steig, E. J., … Taylor, K. C. (2014). The WAIS-Divide deep ice core WD2014 chronology – Part 2: Methane synchronization (68–31 ka BP) and the gas age-ice age difference. Climate of the Past Discussions, 10(4), 3537–3584. (doi:10.5194/cpd-10-3537-2014)
4. Steig, E. J., Huybers, K., Singh, H. A., Steiger, N. J., Ding, Q., Frierson, D. M. W., … White, J. W. C. (2015). Influence of West Antarctic Ice Sheet collapse on Antarctic surface climate. Geophysical Research Letters, 42(12), 4862–4868. (doi:10.1002/2015gl063861)
5. Schoenemann, S. W., & Steig, E. J. (2016). Seasonal and spatial variations of17Oexcessanddexcessin Antarctic precipitation: Insights from an intermediate complexity isotope model. Journal of Geophysical Research: Atmospheres, 121(19), 11,215–11,247. (doi:10.1002/2016jd025117)
6. Garland, J., Jones, T. R., Neuder, M., White, J. W., & Bradley, E. (2019). An information-theoretic approach to extracting climate signals from deep polar ice cores. Chaos: An Interdisciplinary Journal of Nonlinear Science, 29(10), 101105. (doi:10.1063/1.5127211)
7. Markle, B. R., & Steig, E. J. (2021). Improving temperature reconstructions from ice-core water-isotope records. (doi:10.5194/cp-2021-37)
8. Buizert, Christo; Fudge, T.J.; Roberts, William H. G.; Steig, Eric J.; Sherriff-Tadano, Sam; Ritz, Catherine; Lefebvre, Eric; Edwards, Jon; Kawamura, Kenji; Oyabu, Ikumi; Motoyama, Hideaki; Kahle, Emma C.; Jones, Tyler R.; Abe-Ouchi, Ayako; Obase, Takashi; Martin, Carlos; Corr, Hugh; Severinghaus, Jeffrey P.; Beaudette, Ross; Epifanio, Jenna; Brook, Edward J.; Martin, Kaden; Chappellaz, Jérôme; Aoki, Shuji; Nakazawa, Takakiyo; Sowers, Todd A.; Alley, Richard; Ahn, Jinho; Sigl, Michael; Severi, Mirko; Dunbar, Nelia W.; Svensson, Anders; Fegyveresi, John; He, Chengfei; Liu, Zhengyu; Zhu, Jiang; Otto-Bliesner, Bette; Lipenkov, Vladimir Y.; Kameda, Takao; Schwander, Jakob. 2021 in press. Antarctic surface temperature and elevation during the Last Glacial Maximum. Science, 372(6546), 1097–1101 (doi:10.1126/science.abd2897)
9. Markle, B. R., & Steig, E. J. (2022). Improving temperature reconstructions from ice-core water-isotope records. Climate of the Past, 18(6), 1321–1368. (doi:10.5194/cp-18-1321-2022)