&lt;i&gt;Brief communication&lt;/i&gt;  &quot;The 2013 Erebus Glacier tongue calving event&quot;

Abstract. The Erebus Glacier Tongue, a~small floating glacier in southern McMurdo Sound, is one of the best-studied ice tongues in Antarctica. Despite this, its calving on the 27 February 2013 (UTC) was around 10 yr earlier than previously predicted. The calving was likely a result of ocean currents and the absence of fast ice. The subsequent trajectory of the newly-created iceberg supports previous descriptions of the surface ocean circulation in southern McMurdo Sound.

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<i>Brief Communication</i> "The 2013 Erebus Glacier Tongue calving event"

The Cryosphere ◽

10.5194/tc-7-1333-2013 ◽

2013 ◽

Vol 7 (5) ◽

pp. 1333-1337 ◽

Cited By ~ 4

Author(s):

C. L. Stevens ◽

P. Sirguey ◽

G. H. Leonard ◽

T. G. Haskell

Keyword(s):

Ocean Circulation ◽

Ocean Currents ◽

Mcmurdo Sound ◽

Glacier Tongue ◽

Surface Ocean ◽

Fast Ice

Abstract. The Erebus Glacier Tongue, a small floating glacier in southern McMurdo Sound, is one of the best-studied ice tongues in Antarctica. Despite this, its calving on the 27 February 2013 (UTC) was around 10 yr earlier than previously predicted. The calving was likely a result of ocean currents and the absence of fast ice. The subsequent trajectory of the newly created iceberg supports previous descriptions of the surface ocean circulation in southern McMurdo Sound.

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Surface-circulation change in the southwest Pacific Ocean across the Middle Eocene Climatic Optimum: inferences from dinoflagellate cysts and biomarker paleothermometry

Climate of the Past ◽

10.5194/cp-16-1667-2020 ◽

2020 ◽

Vol 16 (5) ◽

pp. 1667-1689

Author(s):

Margot J. Cramwinckel ◽

Lineke Woelders ◽

Emiel P. Huurdeman ◽

Francien Peterse ◽

Stephen J. Gallagher ◽

...

Keyword(s):

Climate Change ◽

Pacific Ocean ◽

Southern Ocean ◽

Ocean Circulation ◽

Middle Eocene ◽

Spatiotemporal Distribution ◽

Ocean Currents ◽

Surface Currents ◽

Surface Ocean

Abstract. Global climate cooled from the early Eocene hothouse (∼52–50 Ma) to the latest Eocene (∼34 Ma). At the same time, the tectonic evolution of the Southern Ocean was characterized by the opening and deepening of circum-Antarctic gateways, which affected both surface- and deep-ocean circulation. The Tasmanian Gateway played a key role in regulating ocean throughflow between Australia and Antarctica. Southern Ocean surface currents through and around the Tasmanian Gateway have left recognizable tracers in the spatiotemporal distribution of plankton fossils, including organic-walled dinoflagellate cysts. This spatiotemporal distribution depends on both the physicochemical properties of the water masses and the path of surface-ocean currents. The extent to which climate and tectonics have influenced the distribution and composition of surface currents and thus fossil assemblages has, however, remained unclear. In particular, the contribution of climate change to oceanographic changes, superimposed on long-term and gradual changes induced by tectonics, is still poorly understood. To disentangle the effects of tectonism and climate in the southwest Pacific Ocean, we target a climatic deviation from the long-term Eocene cooling trend: the Middle Eocene Climatic Optimum (MECO; ∼40 Ma). This 500 kyr phase of global warming was unrelated to regional tectonism, and thus provides a test case to investigate the ocean's physicochemical response to climate change alone. We reconstruct changes in surface-water circulation and temperature in and around the Tasmanian Gateway during the MECO through new palynological and organic geochemical records from the central Tasmanian Gateway (Ocean Drilling Program Site 1170), the Otway Basin (southeastern Australia), and the Hampden Beach section (New Zealand). Our results confirm that dinocyst communities track specific surface-ocean currents, yet the variability within the communities can be driven by superimposed temperature change. Together with published results from the east of the Tasmanian Gateway, our new results suggest a shift in surface-ocean circulation during the peak of MECO warmth. Simultaneous with high sea-surface temperatures in the Tasmanian Gateway area, pollen assemblages indicate warm temperate rainforests with paratropical elements along the southeastern margin of Australia. Finally, based on new age constraints, we suggest that a regional southeast Australian transgression might have been coincident with the MECO.

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The oceanographic contribution of James Croll

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691021000086 ◽

2021 ◽

pp. 1-7

Author(s):

Alastair DAWSON

Keyword(s):

Ocean Circulation ◽

High Latitude ◽

First Principles ◽

Heat Supply ◽

Real Data ◽

Ocean Currents ◽

Ice Ages ◽

Scientific Exploration ◽

The Many

ABSTRACT The research of James Croll on the nature of Ice Ages led him into a detailed investigation of ocean currents. By the early 1870s he had calculated from first principles the quantities of heat delivered by ocean currents to high latitude areas and he understood how this heat supply may have altered drastically during ice ages. The publication of his many papers on ocean currents as well as his book, Climate and Time, coincided with Challenger expedition that, in 1872, embarked on a 4-year voyage of scientific exploration of the world's oceans. The expedition was crucially important for Croll since it enabled him to test his theories of ocean circulation using real data. His novel theories of ocean circulation based on this information conflicted with the established views popularly advocated by William Carpenter but they ultimately prevailed. In the many writings of Croll on ocean currents, we encounter, as with other areas of his research, numerous remarkable ideas many decades ahead their time.

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Surface Ocean Circulation and Variability Determined from Satellite Altimetry

The Ocean Surface ◽

10.1007/978-94-015-7717-5_46 ◽

1985 ◽

pp. 345-350 ◽

Cited By ~ 1

Author(s):

Richard Coleman

Keyword(s):

Ocean Circulation ◽

Satellite Altimetry ◽

Surface Ocean

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Erebus Glacier Tongue, Mcmurdo Sound, Antarctica

Journal of Glaciology ◽

10.1017/s0022143000023340 ◽

1974 ◽

Vol 13 (67) ◽

pp. 27-35 ◽

Cited By ~ 39

Author(s):

G. Holdsworth

Keyword(s):

Shear Stress ◽

Strain Rate ◽

Shear Strain ◽

Longitudinal Strain ◽

Strain Rates ◽

Shear Strain Rate ◽

Mcmurdo Sound ◽

Glacier Tongue ◽

The Past ◽

Image Position

Examination of the past and present behaviour of the Erebus Glacier tongue over the last 60 years indicates that a major calving from the tongue appears to be imminent. Calculations of the regime of the tongue indicate that bottom melt rates may exceed 1 m a−1. By successive mapping of the ice tongue between the years 1947 and 1970, longitudinal strain-rates were determined using the change in distance between a set of 15 teeth, which are a prominent marginal feature of the tongue. Assuming a flow law for ice of the form where τ is the effective shear stress and is the effective shear strain-rate, values of the exponent n = 3 and B = 1 × 108 N m−2 are determined. These are in fair agreement with published values.

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The Trident Pacific model. Part 1: simulating surface ocean currents with a linear model during the 1993-1998 TOPEX/POSEIDON period

Climate Dynamics ◽

10.1007/s003820000100 ◽

2001 ◽

Vol 17 (2-3) ◽

pp. 159-173 ◽

Cited By ~ 6

Author(s):

J.-P. Boulanger

Keyword(s):

Linear Model ◽

Ocean Currents ◽

Surface Ocean

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The role of Pine Island Glacier ice shelf basal channels in deep-water upwelling, polynyas and ocean circulation in Pine Island Bay, Antarctica

Annals of Glaciology ◽

10.3189/2012aog60a062 ◽

2012 ◽

Vol 53 (60) ◽

pp. 123-128 ◽

Cited By ~ 39

Author(s):

Kenneth D. Mankoff ◽

Stanley S. Jacobs ◽

Slawek M. Tulaczyk ◽

Sharon E. Stammerjohn

Keyword(s):

Ocean Circulation ◽

Deep Water ◽

Open Water ◽

Positive Temperature ◽

Ice Shelf ◽

Amundsen Sea ◽

Buoyant Plumes ◽

Surface Circulation ◽

Glacier Ice ◽

Fast Ice

AbstractSeveral hundred visible and thermal infrared satellite images of Antarctica’s southeast Amundsen Sea from 1986 to 2011, combined with aerial observations in 2009, show a strong inverse relation between prominent curvilinear surface depressions and the underlying basal morphology of the outer Pine Island Glacier ice shelf. Shipboard measurements near the calving front reveal positive temperature, salinity and current anomalies indicative of melt-laden, deep-water outflows near and above the larger channel termini. These buoyant plumes rise to the surface and are expressed as small polynyas in the sea ice and thermal signatures in the open water. The warm upwellings also trace the cyclonic surface circulation in Pine Island Bay. The satellite coverage suggests changing modes of ocean/ice interactions, dominated by leads along the ice shelf through 1999, fast ice and polynyas from 2000 to 2007, and larger areas of open water since 2008.

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Linking sardine recruitment in coastal areas to ocean currents using surface drifters and HF radar: a case study in the Gulf of Manfredonia, Adriatic Sea

Ocean Science ◽

10.5194/os-14-1461-2018 ◽

2018 ◽

Vol 14 (6) ◽

pp. 1461-1482 ◽

Cited By ~ 8

Author(s):

Roberta Sciascia ◽

Maristella Berta ◽

Daniel F. Carlson ◽

Annalisa Griffa ◽

Monica Panfili ◽

...

Keyword(s):

Adriatic Sea ◽

Strong Dependence ◽

Early Life History ◽

Ocean Currents ◽

Hf Radar ◽

Residence Times ◽

Sustainable Resource Management ◽

Surface Ocean ◽

Surface Drifters

Abstract. Understanding the role of ocean currents in the recruitment of commercially and ecologically important fish is an important step toward developing sustainable resource management guidelines. To this end, we attempt to elucidate the role of surface ocean transport in supplying recruits of European sardine (Sardina pilchardus) to the Gulf of Manfredonia, a known recruitment area in the Adriatic Sea. Sardine early life history stages (ELHSs) were collected during two cruises to provide observational estimates of their age–size relationship and their passive pelagic larval duration (PPLD). We combine these PPLDs with observations of surface ocean currents to test two hypotheses: (1) ELHSs are transported from remote spawning areas (SAs) by ocean currents to the Gulf of Manfredonia; (2) sardines spawn locally and ELHSs are retained by eddies. A historical surface drifter database is used to test hypothesis 1. Hypothesis 2 is tested by estimating residence times in the Gulf of Manfredonia using surface drifters and virtual particles trajectories that were computed from high-resolution observations of surface currents measured by a high-frequency (HF) radar network. Transport to the Gulf of Manfredonia from remote SAs seems more likely than local spawning and retention given a mismatch between observed PPLDs of 30–50 days and relatively short (<10-day) average residence times. The number and strength of connections between the gulf and remote SAs exhibit a strong dependence on PPLD. For PPLDs of 20 days or less, the gulf is connected to SAs on the western Adriatic coast through transport in the Western Adriatic Current (WAC). SAs on the east coast are more important at longer PPLDs. SAs in the northern and central Adriatic exhibit weak connections at all PPLD ranges considered. These results agree with otolith microstructure analysis, suggesting that the arrival of larvae in the gulf is characterized by repeated pulses from remote SAs. This is the first attempt to describe the processes related to Lagrangian connection to, and retention in, the Gulf of Manfredonia that will be complemented in the future using validated numerical ocean models and biophysical models.

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