The Antarctic sea ice alga Chlamydomonas sp. ICE-L provides insights into adaptive patterns of chloroplast evolution

AbstractThis study presents culture experiments of the cold water species Neogloboquadrina pachyderma (sinistral) and provides new insights into the incorporation of elements in foraminiferal calcite of common and newly established proxies for paleoenvironmental applications (shell Mg/Ca, Sr/Ca and Na/Ca). Specimens were collected from sea ice during the austral winter in the Antarctic Weddell Sea and subsequently cultured at different salinities and a constant temperature. Incorporation of the fluorescent dye calcein showed new chamber formation in the culture at salinities of 30, 31, and 69. Cultured foraminifers at salinities of 46 to 83 only revealed chamber wall thickening, indicated by the fluorescence of the whole shell. Signs of reproduction and the associated gametogenic calcite were not observed in any of the culture experiments. Trace element analyses were performed using an electron microprobe, which revealed increased shell Mg/Ca, Sr/Ca, and Na/Ca values at higher salinities, with Mg/Ca showing the lowest sensitivity to salinity changes. This study enhances the knowledge about unusually high element concentrations in foraminifera shells from high latitudes. Neogloboquadrina pachyderma appears to be able to calcify in the Antarctic sea ice within brine channels, which have low temperatures and exceptionally high salinities due to ongoing sea ice formation.

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Dark metabolism: a molecular insight into how the Antarctic sea‐ice diatom Fragilariopsis cylindrus survives long‐term darkness

New Phytologist ◽

10.1111/nph.15843 ◽

2019 ◽

Vol 223 (2) ◽

pp. 675-691 ◽

Cited By ~ 10

Author(s):

Fraser Kennedy ◽

Andrew Martin ◽

John P. Bowman ◽

Richard Wilson ◽

Andrew McMinn

Keyword(s):

Sea Ice ◽

Antarctic Sea Ice ◽

Fragilariopsis Cylindrus ◽

Dark Metabolism ◽

The Antarctic ◽

Insight Into

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Thermodynamics of slush and snow–ice formation in the Antarctic sea-ice zone

Deep Sea Research Part II Topical Studies in Oceanography ◽

10.1016/j.dsr2.2016.03.008 ◽

2016 ◽

Vol 131 ◽

pp. 75-83 ◽

Cited By ~ 7

Author(s):

Mathilde Jutras ◽

Martin Vancoppenolle ◽

Antonio Lourenço ◽

Frédéric Vivier ◽

Gauthier Carnat ◽

...

Keyword(s):

Sea Ice ◽

Ice Formation ◽

Antarctic Sea Ice ◽

The Antarctic

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Last Glacial Maximum Antarctic sea ice linked with global mean ocean temperature: evidence from PMIP3, PMIP4 and MIROC-4m simulations

10.5194/egusphere-egu21-3550 ◽

2021 ◽

Author(s):

Tristan Vadsaria ◽

Sam Sherriff-Tadano ◽

Ayako Abe-Ouchi ◽

Takashi Obase ◽

Wing-Le Chan ◽

...

Keyword(s):

Southern Ocean ◽

Sea Ice ◽

Last Glacial Maximum ◽

Ocean Circulation ◽

Glacial Maximum ◽

Ocean Temperature ◽

Sea Ice Extent ◽

Last Glacial ◽

Antarctic Sea Ice ◽

The Antarctic

<p>Southern Ocean sea ice and oceanic fronts are known to play an important role on the climate system, carbon cycles, bottom ocean circulation, and Antarctic ice sheet. However, many models of the previous Past-climate Model Intercomparison Project (PMIP) underestimated sea-ice extent (SIE) for the Last Glacial Maximum (LGM)(Roche et al., 2012; Marzocchi and Jensen, 2017), mainly because of surface bias (Flato et al., 2013) that may have an impact on mean ocean temperature (MOT). Indeed, recent studies further suggest an important link between Southern Ocean sea ice and mean ocean temperature (Ferrari et al., 2014; Bereiter et al., 2018 among others). Misrepresent the Antarctic sea-ice extent could highly impact deep ocean circulation, the heat transport and thus the MOT. In this study, we will stress the relationship between the distribution of Antarctic sea-ice extent and the MOT through the analysis of the PMIP3 and PMIP4 exercise and by using a set of MIROC models. To date, the latest version of MIROC improve its representation of the LGM Antarctic sea-ice extent, affecting the deep circulation and the MOT distribution (Sherriff-Tadano et al., under review).</p><p>Our results show that available PMIP4 models have an overall improvement in term of LGM sea-ice extent compared to PMIP3, associated to colder deep and bottom ocean temperature. Focusing on MIROC (4m) models, we show that models accounting for Southern Ocean sea-surface temperature (SST) bias correction reproduce an Antarctic sea-ice extent, 2D-distribution, and seasonal amplitude in good agreement with proxy-based data. Finally, using PMIP-MIROC analyze, we show that it exists a relationship between the maximum SIE and the MOT, modulated by the Antarctic intermediate and bottom waters.</p>

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Analysis of the temporal–spatial changes in surface radiation budget over the Antarctic sea ice region

The Science of The Total Environment ◽

10.1016/j.scitotenv.2019.02.264 ◽

2019 ◽

Vol 666 ◽

pp. 1134-1150 ◽

Cited By ~ 1

Author(s):

Teng Zhang ◽

Chunxia Zhou ◽

Lei Zheng

Keyword(s):

Sea Ice ◽

Surface Radiation ◽

Radiation Budget ◽

Antarctic Sea Ice ◽

Surface Radiation Budget ◽

Spatial Changes ◽

The Antarctic

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Growth and longevity of the Antarctic scallop Adamussium colbecki under annual and multiannual sea ice

Antarctic Science ◽

10.1017/s0954102020000322 ◽

2020 ◽

Vol 32 (6) ◽

pp. 466-475

Author(s):

Kelly E. Cronin ◽

Sally E. Walker ◽

Roger Mann ◽

Antonie S. Chute ◽

M. Chase Long ◽

...

Keyword(s):

Sea Ice ◽

Nutrient Availability ◽

Life Histories ◽

Ecosystem Engineer ◽

Marine Ecosystem ◽

Individual Variability ◽

Marine Communities ◽

Antarctic Sea Ice ◽

The Antarctic ◽

Adamussium Colbecki

AbstractEcosystem engineers such as the Antarctic scallop (Adamussium colbecki) shape marine communities. Thus, changes to their lifespan and growth could have far-reaching effects on other organisms. Sea ice is critical to polar marine ecosystem function, attenuating light and thereby affecting nutrient availability. Sea ice could therefore impact longevity and growth in polar bivalves unless temperature is the overriding factor. Here, we compare the longevity and growth of A. colbecki from two Antarctic sites: Explorers Cove and Bay of Sails, which differ by sea-ice cover, but share similar seawater temperatures, the coldest on Earth (-1.97°C). We hypothesize that scallops from the multiannual sea-ice site will have slower growth and greater longevity. We found maximum ages to be similar at both sites (18–19 years). Growth was slower, with higher inter-individual variability, under multiannual sea ice than under annual sea ice, which we attribute to patchier nutrient availability under multiannual sea ice. Contrary to expectations, A. colbecki growth, but not longevity, is affected by sea-ice duration when temperatures are comparable. Recent dramatic reductions in Antarctic sea ice and predicted temperature increases may irrevocably alter the life histories of this ecosystem engineer and other polar organisms.

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Impacts of Interactive Stratospheric Chemistry on Antarctic and Southern Ocean Climate Change in the Goddard Earth Observing System, Version 5 (GEOS-5)

Journal of Climate ◽

10.1175/jcli-d-15-0572.1 ◽

2016 ◽

Vol 29 (9) ◽

pp. 3199-3218 ◽

Cited By ~ 17

Author(s):

Feng Li ◽

Yury V. Vikhliaev ◽

Paul A. Newman ◽

Steven Pawson ◽

Judith Perlwitz ◽

...

Keyword(s):

Climate Change ◽

Southern Ocean ◽

Sea Ice ◽

Ozone Depletion ◽

Stratospheric Ozone ◽

Meridional Overturning Circulation ◽

Stratospheric Chemistry ◽

Earth Observing System ◽

Antarctic Sea Ice ◽

The Antarctic

Abstract Stratospheric ozone depletion plays a major role in driving climate change in the Southern Hemisphere. To date, many climate models prescribe the stratospheric ozone layer’s evolution using monthly and zonally averaged ozone fields. However, the prescribed ozone underestimates Antarctic ozone depletion and lacks zonal asymmetries. This study investigates the impact of using interactive stratospheric chemistry instead of prescribed ozone on climate change simulations of the Antarctic and Southern Ocean. Two sets of 1960–2010 ensemble transient simulations are conducted with the coupled ocean version of the Goddard Earth Observing System Model, version 5: one with interactive stratospheric chemistry and the other with prescribed ozone derived from the same interactive simulations. The model’s climatology is evaluated using observations and reanalysis. Comparison of the 1979–2010 climate trends between these two simulations reveals that interactive chemistry has important effects on climate change not only in the Antarctic stratosphere, troposphere, and surface, but also in the Southern Ocean and Antarctic sea ice. Interactive chemistry causes stronger Antarctic lower stratosphere cooling and circumpolar westerly acceleration during November–January. It enhances stratosphere–troposphere coupling and leads to significantly larger tropospheric and surface westerly changes. The significantly stronger surface wind stress trends cause larger increases of the Southern Ocean meridional overturning circulation, leading to year-round stronger ocean warming near the surface and enhanced Antarctic sea ice decrease.

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