Counting Harp Seals with ultra-violet photography

Polar Record ◽  
1976 ◽  
Vol 18 (114) ◽  
pp. 269-277 ◽  
Author(s):  
D. M. Lavigne
Keyword(s):  
North Atlantic ◽  
White Sea ◽  
North Atlantic Ocean ◽  
Ultra Violet ◽  
The Arctic ◽  
Hudson Bay ◽  
The North ◽  
Breeding Populations ◽  
Pagophilus Groenlandicus ◽  
Arctic Ice

The Harp Seal Pagophilus groenlandicus is a gregarious, migratory seal inhabiting Arctic and sub-Arctic waters of the North Atlantic Ocean. In spring, asthe ice recedes, the largest of three known breeding populations migrates up the east coas of Canada from the Gulf of St Lawrence, along the coast of Labrador, to the Canadian Archipelago, Hudson Bay, and the west coast of Greenland. After spending the summer feeding in Arctic waters, the seals move southward ahead of the Arctic ice pack, reaching the coast of Labrador and the Gulf of St Lawrence sometime in late December or early January. They reappear at the end of February and in early March in whelping ‘patches’ or concentrations on ice inthe Gulf of St Lawrence west of the Magdalen Islands, and off the coast of Labrador in an areaknown as the ‘Front’. One of the two smaller and probably distinct breeding populations is to be found in the White Sea, the other in the Vestisen [West Ice] between Jan Mayen and Svalbard.

scholarly journals Cooling down the world oceans and the earth by enhancing the North Atlantic Ocean current

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Julian David Hunt ◽  
Andreas Nascimento ◽  
Fabio A. Diuana ◽  
Natália de Assis Brasil Weber ◽  
Gabriel Malta Castro ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Arctic Ocean ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
The Arctic ◽  
Ocean Current ◽  
The North ◽  
The Arctic Ocean ◽  
Albedo Effect ◽  
Arctic Atmosphere

AbstractThe world is going through intensive changes due to global warming. It is well known that the reduction in ice cover in the Arctic Ocean further contributes to increasing the atmospheric Arctic temperature due to the reduction of the albedo effect and increase in heat absorbed by the ocean’s surface. The Arctic ice cover also works like an insulation sheet, keeping the heat in the ocean from dissipating into the cold Arctic atmosphere. Increasing the salinity of the Arctic Ocean surface would allow the warmer and less salty North Atlantic Ocean current to flow on the surface of the Arctic Ocean considerably increasing the temperature of the Arctic atmosphere and release the ocean heat trapped under the ice. This paper argues that if the North Atlantic Ocean current could maintain the Arctic Ocean ice-free during the winter, the longwave radiation heat loss into space would be larger than the increase in heat absorption due to the albedo effect. This paper presents details of the fundamentals of the Arctic Ocean circulation and presents three possible approaches for increasing the salinity of the surface water of the Arctic Ocean. It then discusses that increasing the salinity of the Arctic Ocean would warm the atmosphere of the Arctic region, but cool down the oceans and possibly the Earth. However, it might take thousands of years for the effects of cooling the oceans to cool the global average atmospheric temperature.

scholarly journals How does the Arctic affect North Atlantic climate? Fresh perspectives on a long-standing question.

2021 ◽  
Author(s):  
Marilena Oltmanns ◽  
N. Penny Holliday ◽  
James Screen ◽  
D. Gwyn Evans ◽  
Simon A. Josey ◽  
...  
Keyword(s):  
Ocean Circulation ◽  
North Atlantic ◽  
Heat Waves ◽  
Rapid Change ◽  
The Arctic ◽  
Extreme Weather Events ◽  
Weather Extremes ◽  
Arctic Warming ◽  
The North ◽  
Arctic Ice

<p>Recent decades have been characterised by amplified Arctic warming and increased occurrence of extreme weather events in the North Atlantic region. While earlier studies noticed statistical links between high-latitude warming and mid-latitude weather extremes, the underlying dynamical connections remained elusive. Combining different data products, I will demonstrate a new mechanism linking Arctic ice losses with cold anomalies and storms in the subpolar region in winter, and with heat waves and droughts over Europe summer. Considering feedbacks of the identified mechanism on the Arctic Ocean circulation, I will further present new support for the potential of Arctic warming to trigger a rapid change in climate.</p>

scholarly journals XXVI. On the Rhizopodal Fauna of the Deep Sea

1870 ◽  
Vol 18 (114-122) ◽  
pp. 59-62 ◽  
Keyword(s):  
North Atlantic ◽  
Deep Sea ◽  
North Atlantic Ocean ◽  
General Rule ◽  
Equatorial Region ◽  
The Arctic ◽  
Shallow Waters ◽  
Arctic Seas ◽  
The North ◽  
And Diffusion

The Author commences by referring to the knowledge of the Rhizopodal Fauna of the Deep Sea which has been gradually acquired by the examination of specimens of the bottom brought up by the Sounding-apparatus; and states that whilst this method of investigation has made known the vast extent and diffusion of Foramimferal life at great depths,-especially in the case of Globigerina-mud , which has been proved to cover a large part of the bottom of the North Atlantic Ocean,—it has not added any new Generic types to those discoverable in comparatively shallow waters. With the exception of a few forms, which, like find their most congenial home, and attain their greatest development, at great depths, the general rule has seemed to be that Foramimfera are progressively dwarfed in proportion to increase of depth, as they are y a change from a warmer to a colder climate; those which are brought up from great depths in the Equatorial region bearing a much stronger resemblance to those of the colder-temperate, or even of the Arctic seas, than to the littoral forms of their own region.

scholarly journals Response of Thermohaline Circulation to Freshwater Forcing under Present-Day and LGM Conditions

2008 ◽  
Vol 21 (10) ◽  
pp. 2239-2258 ◽  
Author(s):  
Aixue Hu ◽  
Bette L. Otto-Bliesner ◽  
Gerald A. Meehl ◽  
Weiqing Han ◽  
Carrie Morrill ◽  
...  
Keyword(s):  
North Atlantic ◽  
Thermohaline Circulation ◽  
North Atlantic Ocean ◽  
The Arctic ◽  
Bering Strait ◽  
Climate System Model ◽  
The North ◽  
Freshwater Forcing ◽  
Bering Strait Throughflow ◽  
The North Atlantic

Abstract Responses of the thermohaline circulation (THC) to freshwater forcing (hosing) in the subpolar North Atlantic Ocean under present-day and the last glacial maximum (LGM) conditions are investigated using the National Center for Atmospheric Research Community Climate System Model versions 2 and 3. Three sets of simulations are analyzed, with each set including a control run and a freshwater hosing run. The first two sets are under present-day conditions with an open and closed Bering Strait. The third one is under LGM conditions, which has a closed Bering Strait. Results show that the THC nearly collapses in all three hosing runs when the freshwater forcing is turned on. The full recovery of the THC, however, is at least a century earlier in the open Bering Strait run than the closed Bering Strait and LGM runs. This is because the excessive freshwater is diverged almost equally toward north and south from the subpolar North Atlantic when the Bering Strait is open. A significant portion of the freshwater flowing northward into the Arctic exits into the North Pacific via a reversed Bering Strait Throughflow, which accelerates the THC recovery. When the Bering Strait is closed, this Arctic to Pacific transport is absent and freshwater can only be removed through the southern end of the North Atlantic. Together with the surface freshwater excess due to precipitation, evaporation, river runoff, and melting ice in the closed Bering Strait experiments after the hosing, the removal of the excessive freshwater takes longer, and this slows the recovery of the THC. Although the background conditions are quite different between the present-day closed Bering Strait run and the LGM run, the THC responds to the freshwater forcing added in the North Atlantic in a very similar manner.

Arctic closure as a trigger for Atlantic overturning at the Eocene-Oligocene Transition

2020 ◽  
Author(s):  
David Hutchinson ◽  
Helen Coxall ◽  
Matt O'Regan ◽  
Johan Nilsson ◽  
Rodrigo Caballero ◽  
...  
Keyword(s):  
North Atlantic ◽  
North Pacific ◽  
North Atlantic Ocean ◽  
Late Eocene ◽  
Meridional Overturning Circulation ◽  
The Arctic ◽  
Deep Circulation ◽  
The North ◽  
The North Atlantic ◽  
The North Pacific

<p><strong>The Eocene-Oligocene Transition (EOT), approximately 34 Ma ago, marks a period of major global cooling and inception of the Antarctic ice sheet. Proxies of deep circulation suggest a contemporaneous onset or strengthening of the Atlantic meridional overturning circulation (AMOC). Proxy evidence of gradual salinification of the North Atlantic and tectonically driven isolation of the Arctic suggest that closing the Arctic-Atlantic gateway could have triggered the AMOC at the EOT. We demonstrate this trigger of the AMOC using a new paleoclimate model with late Eocene boundary conditions. The control simulation reproduces Eocene observations of low Arctic salinities. Subsequent closure of the Arctic-Atlantic gateway triggers the AMOC by blocking freshwater inflow from the Arctic. Salt advection feedbacks then lead to cessation of overturning in the North Pacific. These circulation changes imply major warming of the North Atlantic Ocean, and simultaneous cooling of the North Pacific, but no interhemispheric change in temperatures.</strong></p>

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