Antarctic icebergs reorganize ocean circulation during Pleistocene glacials

  title={Antarctic icebergs reorganize ocean circulation during Pleistocene glacials},
  author={Aidan Starr and Ian R. Hall and Stephen Barker and T. Rackow and Xu Zhang and Sidney R. Hemming and H. J. L. van der Lubbe and Gregor Knorr and Melissa A. Berke and Grant R. Bigg and Alejandra Cartagena-Sierra and Francisco J. Jim{\'e}nez-Espejo and Xun Gong and Jens Gruetzner and Nambiyathodi Lathika and Leah J. LeVay and Rebecca Robinson and Martin Ziegler},
The dominant feature of large-scale mass transfer in the modern ocean is the Atlantic meridional overturning circulation (AMOC). The geometry and vigour of this circulation influences global climate on various timescales. Palaeoceanographic evidence suggests that during glacial periods of the past 1.5 million years the AMOC had markedly different features from today 1 ; in the Atlantic basin, deep waters of Southern Ocean origin increased in volume while above them the core of the North… Expand
5 Citations
Neodymium isotope evidence for coupled Southern Ocean circulation and Antarctic climate throughout the last 118,000 years
Abstract The chain of events surrounding the initiation and intensification of the last glacial cycle remain relatively poorly understood. In particular, the role of Southern Ocean paleocirculationExpand
Opposite dust grain-size patterns in the Pacific and Atlantic sectors of the Southern Ocean during the last 260,000 years
Abstract Downcore sediment grain-size records of mineral dust (2–10 μm) can provide key insights into changes in wind strength and source-area characteristics over glacial-interglacial timescales.Expand
Semi-automated tracking of iceberg B43 using Sentinel-1 SAR images via Google Earth Engine
Abstract. Sentinel-1 C-band synthetic aperture radar (SAR) images can be used to observe the drift of icebergs over the Southern Ocean with around 1–3 days of temporal resolution and 10–40 m ofExpand
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Following a high-end projection for mass loss from the Greenland and Antarctic ice-sheets, a freshwater forcing was applied to the ocean surface in the coupled climate model EC-Earthv2.2 to study theExpand


Icebergs not the trigger for North Atlantic cold events
A systematic delay between pronounced surface cooling and the arrival of ice-rafted debris at a site southwest of Iceland over the past four glacial cycles is demonstrated, implying that in general icebergs arrived too late to have triggered cooling, and is suggested thatrupt transitions to stadial conditions should be considered as a nonlinear response to more gradual cooling across the North Atlantic. Expand
Antarctic sea ice control on ocean circulation in present and glacial climates
This study shows that this rearrangement of deep water masses is dynamically linked to the expansion of summer sea ice around Antarctica, and may help quantify the ocean’s role in regulating atmospheric carbon dioxide on glacial–interglacial timescales. Expand
Incursions of southern-sourced water into the deep North Atlantic during late Pliocene glacial intensification
The circulation and internal structure of the oceans exert a strong influence on Earth’s climate because they control latitudinal heat transport and the segregation of carbon between the atmosphereExpand
Obliquity Control On Southern Hemisphere Climate During The Last Glacial
The authors' analyses suggest that Antarctic sea-ice expansion at 28.5 ka altered the location and intensity of the Southern Hemisphere storm track, triggering regional cooling over Patagonia of 5°C that extends across the wider mid-southern latitudes, and highlights the dominant role that orbital changes can play in driving Southern Hemisphere glacial climate via the sensitivity of mid-latitude regions to changes in AntarcticSea-ice extent. Expand
Glacial Southern Ocean freshening at the onset of the Middle Pleistocene Climate Transition
Changes in Southern Ocean hydrography may have played an important role in the Middle Pleistocene Transition (MPT), particularly through their impact on ocean circulation and atmospheric CO2Expand
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A major disruption of the ocean thermohaline circulation (THC) system during the mid-Pleistocene transition effectively marks the first 100-thousand-year cycle, including an exceptional weakening through a critical interglacial (MIS 23) at ~900 thousand years ago. Expand
Plio-Pleistocene Ice Volume, Antarctic Climate, and the Global δ18O Record
We propose that from ∼3 to 1 million years ago, ice volume changes occurred in both the Northern and Southern Hemispheres, each controlled by local summer insolation. Because Earth's orbitalExpand
Millennial-scale variability in Antarctic ice-sheet discharge during the last deglaciation
Two well-dated, high-resolution IBRD records are presented that capture a spatially integrated signal of AIS variability during the last deglaciation, suggesting that small perturbations to the ice sheet can be substantially enhanced, providing a possible mechanism for rapid sea-level rise. Expand
Southern Ocean origin for the resumption of Atlantic thermohaline circulation during deglaciation
It is found that a gradual warming in the Southern Ocean during deglaciation induces an abrupt resumption of the interglacial mode of the thermohaline circulation, triggered by increased mass transport into the Atlantic Ocean via the warm (Indian Ocean) and cold (Pacific Ocean) water route. Expand
Southern Ocean sea-ice extent, productivity and iron flux over the past eight glacial cycles
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