USAP-DC

1043500/Sowers

This award supports a project to develop a 50 yr resolution methane data set that will play a pivotal role in developing the WAIS Divide timescale as well as providing a common stratigraphic framework for comparing climate records from Greenland and West Antarctica. Even higher resolution data are proposed for key intervals to assist in precisely defining the phasing of abrupt climate change between the hemispheres. Concurrent analysis of a suit of samples from both the WAIS Divide and GISP-2 cores throughout the last 110,000 years is also proposed, to establish the interpolar methan (CH4) gradient that will be used to identify geographic areas responsible for the climate related methane emission changes. The intellectual merit of the proposed work is that it will provide chronological control needed to examine the timing of changes in climate proxies, and critical chronological ties to the Greenland ice core records via methane variations. One main objective is to understand the interpolar timing of millennial-scale climate change. This is an important scientific goal relevant to understanding climate change mechanisms in general. The proposed work will help establish a chronological framework for addressing these issues. In addition, this proposal addresses the question of what methane sources were active during the ice age, through the work on the interpolar methane gradient. This work is directed at the fundamental question of what part of the biosphere controlled past methane variations, and is important for developing more sophisticated understanding of those variations. The broader impacts of the work are that the ultra-high resolution CH4 record will directly benefit all ice core paleoclimate research and the chronological refinements will impact paleoclimate studies that rely on ice core timescales for correlation purposes. The project will support both graduate and undergraduate students and the PIs will participate in outreach to the public.

Person	Role
Rhodes, Rachel	Co-Investigator
Brook, Edward J.	Investigator
McConnell, Joseph	Co-Investigator

Antarctic Glaciology

Award # 1043518

NSIDC-0628_1
NSF-ANT10-43518

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	Continuous, Ultra-high Resolution WAIS-Divide Ice Core Methane Record 9.8-67.2 ka BP	None	exist
NCEI	Methan record	None	exist
USAP-DC	Early Holocene methane records from Siple Dome, Antarctica	None	exist

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2. Sigl M, Fudge TJ, Winstrup M, Cole-Dai J, Ferris D, McConnell JR, Taylor KC, Welten KC, Woodruff TE, Adolphi F, Bisiaux M, Brook EJ, Buizert C, Caffee MW, Dunbar NW, Edwards R, Geng L, Iverson N, Koffman B, Layman L, Maselli OJ, McGwire K, Muscheler R, Nishiizumi K, Pasteris DR, Rhodes RH, Sowers TA. 2016. The WAIS Divide deep ice core WD2014 chronology -Part 2: Annual-layer counting (0.31 ka BP). Climate of the Past, 12, p. 769-786. doi: 10.5194/cp-12-769-2016. (doi:10.5194/cp-12-769-2016)
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5. Fudge, T. J., Markle, B. R., Cuffey, K. M., Buizert, C., Taylor, K. C., Steig, E. J., … Koutnik, M. (2016). Variable relationship between accumulation and temperature in West Antarctica for the past 31,000 years. Geophysical Research Letters, 43(8), 3795–3803. (doi:10.1002/2016gl068356)
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