Summer sea-ice variability on the Antarctic margin during the last glacial period reconstructed from snow petrel (<i>Pagodroma nivea</i>) stomach-oil deposits
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Published:2022-03-02
Issue:2
Volume:18
Page:381-403
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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:
McClymont Erin L.ORCID, Bentley Michael J.ORCID, Hodgson Dominic A., Spencer-Jones Charlotte L., Wardley Thomas, West Martin D., Croudace Ian W., Berg Sonja, Gröcke Darren R.ORCID, Kuhn GerhardORCID, Jamieson Stewart S. R., Sime LouiseORCID, Phillips Richard A.
Abstract
Abstract. Antarctic sea ice is a critical component of the climate
system affecting a range of physical and biogeochemical feedbacks and
supporting unique ecosystems. During the last glacial stage, Antarctic sea
ice was more extensive than today, but uncertainties in geological (marine
sediments), glaciological (ice core), and climate model reconstructions of
past sea-ice extent continue to limit our understanding of its role in the
Earth system. Here, we present a novel archive of past sea-ice environments
from regurgitated stomach oils of snow petrels (Pagodroma nivea) preserved at nesting
sites in Dronning Maud Land, Antarctica. We show that by combining
information from fatty acid distributions and their stable carbon isotope
ratios with measurements of bulk carbon and nitrogen stable isotopes and
trace metal data, it is possible to reconstruct changing snow petrel diet
within Marine Isotope Stage 2 (ca. 24.3–30.3 cal kyr BP). We show that, as today, a mixed diet of krill and fish characterizes much of the record.
However, between 27.4 and 28.7 cal kyr BP signals of krill almost disappear. By linking dietary signals in the stomach-oil deposits to modern feeding habits and foraging ranges, we infer the use by snow petrels of open-water habitats (“polynyas”) in the sea ice during our interval of study. The periods when
consumption of krill was reduced are interpreted to correspond to the
opening of polynyas over the continental shelf, which became the preferred
foraging habitat. Our results show that extensive, thick, and multiyear sea ice was not always present close to the continent during the last glacial stage and highlight the potential of stomach-oil deposits as a palaeoenvironmental archive of Southern Ocean conditions.
Funder
H2020 European Research Council Deutsche Forschungsgemeinschaft
Publisher
Copernicus GmbH
Subject
Paleontology,Stratigraphy,Global and Planetary Change
Reference133 articles.
1. Ackley, S. F., Xie, H., and Tichenor, E. A.: Ocean heat flux under Antarctic sea ice in the Bellingshausen and Amundsen Seas: two case studies, Ann. Glaciol., 56, 200–210, 2015. 2. Adkins, J. F.: The role of deep ocean circulation in setting glacial
climates, Paleoceanography, 28, 539–561, https://doi.org/10.1002/palo.20046, 2013. 3. Adkins, J. F., McIntyre, K., and Schrag, D. P.: The Salinity, Temperature,
and δ18O of the Glacial Deep Ocean, Science, 298, 1769–1773,
2002. 4. Aiello, A., Fattorusso, E., Menna, M., Vitalone, R., Schröder, H. C.,
and Müller, W. E. G.: Mumijo traditional medicine: fossil deposits from
antarctica (chemical composition and beneficial bioactivity), Evid.-Based Compl. Alt., 2011, 738131–738131, https://doi.org/10.1093/ecam/nen072, 2011. 5. Ainley, D. G., O'Connor, E. F., and Boekelheide, R. J.: The marine ecology
of birds in the Ross Sea, Antarctica, in: American Ornithologist's Union
Ornithological Monograph, 97, 1–97, https://doi.org/10.2307/40166773, 1984.
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