A 2700-year annual timescale and accumulation history for an ice core from Roosevelt Island, West Antarctica
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Published:2019-04-10
Issue:2
Volume:15
Page:751-779
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ISSN:1814-9332
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Container-title:Climate of the Past
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language:en
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Short-container-title:Clim. Past
Author:
Winstrup MaiORCID, Vallelonga PaulORCID, Kjær Helle A., Fudge Tyler J., Lee James E.ORCID, Riis Marie H., Edwards RossORCID, Bertler Nancy A. N.ORCID, Blunier ThomasORCID, Brook Ed J.ORCID, Buizert ChristoORCID, Ciobanu Gabriela, Conway HowardORCID, Dahl-Jensen Dorthe, Ellis AjaORCID, Emanuelsson B. DanielORCID, Hindmarsh Richard C. A.ORCID, Keller Elizabeth D., Kurbatov Andrei V.ORCID, Mayewski Paul A., Neff Peter D., Pyne Rebecca L., Simonsen Marius F., Svensson AndersORCID, Tuohy Andrea, Waddington Edwin D., Wheatley Sarah
Abstract
Abstract. We present a 2700-year annually resolved chronology and snow accumulation
history for the Roosevelt Island Climate Evolution (RICE) ice core, Ross Ice
Shelf, West Antarctica. The core adds information on past accumulation
changes in an otherwise poorly constrained sector of Antarctica. The timescale was constructed by identifying annual cycles in
high-resolution impurity records, and it constitutes the top part of the
Roosevelt Island Ice Core Chronology 2017 (RICE17). Validation by volcanic
and methane matching to the WD2014 chronology from the WAIS Divide ice core
shows that the two timescales are in excellent agreement. In a companion
paper, gas matching to WAIS Divide is used to extend the timescale for the
deeper part of the core in which annual layers cannot be identified. Based on the annually resolved timescale, we produced a record of past snow
accumulation at Roosevelt Island. The accumulation history shows that
Roosevelt Island experienced slightly increasing accumulation rates between
700 BCE and 1300 CE, with an average accumulation of 0.25±0.02 m
water equivalent (w.e.) per year. Since 1300 CE, trends in the accumulation
rate have been consistently negative, with an acceleration in the rate of
decline after the mid-17th century. The current accumulation rate at
Roosevelt Island is 0.210±0.002 m w.e. yr−1 (average since 1965 CE, ±2σ), and it is rapidly declining with a trend corresponding to
0.8 mm yr−2. The decline observed since the mid-1960s is 8 times faster
than the long-term decreasing trend taking place over the previous
centuries, with decadal mean accumulation rates consistently being below
average. Previous research has shown a strong link between Roosevelt Island
accumulation rates and the location and intensity of the Amundsen Sea Low,
which has a significant impact on regional sea-ice extent. The decrease in
accumulation rates at Roosevelt Island may therefore be explained in terms
of a recent strengthening of the ASL and the expansion of sea ice in the eastern
Ross Sea. The start of the rapid decrease in RICE accumulation rates
observed in 1965 CE may thus mark the onset of significant increases in
regional sea-ice extent.
Funder
Carlsbergfondet European Research Council Office of Polar Programs Victoria University of Wellington Antarctica New Zealand
Publisher
Copernicus GmbH
Subject
Paleontology,Stratigraphy,Global and Planetary Change
Reference102 articles.
1. Abbott, P. M., Davies, S. M., Steffensen, J. P., Pearce, N. J. G., Bigler,
M., Johnsen, S. J., Seierstad, I. K., Svensson, A., and Wastegård, S.: A
detailed framework of Marine Isotope Stages 4 and 5 volcanic events recorded
in two Greenland ice-cores, Quaternary Sci. Rev., 36, 59–77,
https://doi.org/10.1016/j.quascirev.2011.05.001, 2012. 2. Alley, R. B., Meese, D. A., Shuman, C. A., Gow, A. J., Taylor, K. C.,
Grootes, P. M., White, J. W. C., Ram, M., Waddington, E. D., Mayewski, P. A., and Zielinski, G. A.: Abrupt increase in Greenland snow accumulation at the
end of the Younger Dryas event, Nature, 362, 527–529, https://doi.org/10.1038/362527a0,
1993. 3. Andersen, K., Svensson, A., Johnsen, S., Rasmussen, S., Bigler, M.,
Röthlisberger, R., Ruth, U., Siggaard-Andersen, M.-L., Steffensen, J.,
Dahl-Jensen, D., Vinther, B., and Clausen, H.: The Greenland Ice Core
Chronology 2005, 15–42ka. Part 1: constructing the time scale, Quaternary Sci. Rev., 25, 3246–3257, https://doi.org/10.1016/j.quascirev.2006.08.002, 2006. 4. Arblaster, J. M., Meehl, G. A., and Karoly, D. J.: Future climate change in
the Southern Hemisphere: Competing effects of ozone and greenhouse gases,
Geophys. Res. Lett., 38, 1–6, https://doi.org/10.1029/2010GL045384, 2011. 5. Arienzo, M. M., McConnell, J. R., Chellman, N., Criscitiello, A. S., Curran,
M., Fritzsche, D., Kipfstuhl, S., Mulvaney, R., Nolan, M., Opel, T., Sigl,
M., and Steffensen, J. P.: A Method for Continuous 239Pu Determinations in
Arctic and Antarctic Ice Cores, Environ. Sci. Technol., 50, 7066–7073,
https://doi.org/10.1021/acs.est.6b01108, 2016.
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