scholarly journals Late Quaternary Marine and Terrestrial Environments, Northwestern Baffin Island, Northwest Territories

2007 ◽  
Vol 48 (1) ◽  
pp. 85-95 ◽  
Author(s):  
Susan K. Short ◽  
John T. Andrews ◽  
Kerstin M. Williams ◽  
Nancy J. Weiner ◽  
Scott A. Elias
Keyword(s):  
Sea Ice ◽  
Late Quaternary ◽  
Major Change ◽  
Local Environment ◽  
High Arctic ◽  
Baffin Island ◽  
Radiocarbon Dates ◽  
Terrestrial Environments ◽  
Ice Conditions ◽  
Diatom Productivity

ABSTRACT Paleoenvironmental data were analyzed from terrestrial, lake, and marine sediments collected near Arctic Bay, Baffin Island, N.W.T. Eighteen new radiocarbon dates provide chronological control, superseding earlier results. Spuriously old dates were obtained from both sandy peats and low-organic lake sediments. The most reliable dates were from marine shells and foraminifera. They indicate that déglaciation was underway by 9000 BP rather than 16,000 BP. Over the period of the record, the local environment was characterized by a high arctic pollen assemblage dominated by grass, sedge, and willow; a middle Holocene warm period is indicated by increased willow, herb, and moss values. Sea-ice conditions were severe enough to inhibit the growth of diatoms until ca. 6300 BP and ice proximal and deglacial conditions prevailed in the fiords until ca. 6000 BP. Diatom productivity increased between 3000 BP and 2500 BP, suggesting warmer surface waters and less sea ice. After 2000 BP diatom accumulation decreased sharply, due to a cooling of climate. The foraminifera indicate a major change in bottom water conditions ca. 4000 BP as the benthic species shift from a calcareous to an arenaceous assemblage.

Late Quaternary paleoceanography of the western Baffin Bay region: evidence from fossil diatoms

1990 ◽  
Vol 27 (11) ◽  
pp. 1487-1494 ◽  
Author(s):  
Kerstin M. Williams
Keyword(s):  
Sea Ice ◽  
East Coast ◽  
Late Quaternary ◽  
Baffin Island ◽  
Ocean Water ◽  
Sea Ice Extent ◽  
Baffin Bay ◽  
Oceanographic Variables ◽  
Diatom Productivity ◽  
Fossil Diatoms

Seven marine cores from the east coast of Baffin Island were examined for variations in diatom content. The cores have good age control and were used for Holocene paleoceanographic reconstruction. A diatom barren zone or a zone of much reduced diatom productivity is evident some time during the early to middle Holocene. This zone ends earlier in the southern area than farther north. The changes in diatom productivity may be caused by changing oceanographic variables such as sea ice extent and the presence of a meltwater cap during deglaciation. Light isotope 18O events ("meltwater spikes") generally coincide with barren or reduced productivity zones in the cores from the middle and southern part of the shelf and from Jones Sound, suggesting a general surficial cooling of the fjord and ocean water. If diatom productivity was depressed because of a meltwater cap over the core sites with increasing sea ice extent, the theory of a general "marine optimum" in all of Baffin Bay and Davis Strait from 8000 to 6000 BP may have to be modified.

The last glaciation and sea level history of Fosheim Peninsula, Ellesmere Island, Canadian High Arctic

1996 ◽  
Vol 33 (7) ◽  
pp. 1075-1086 ◽  
Author(s):  
Trevor Bell
Keyword(s):  
High Arctic ◽  
Radiocarbon Dates ◽  
The Holocene ◽  
Ice Caps ◽  
Marine Deposits ◽  
Last Glaciation ◽  
Maximum Elevation ◽  
Glacier Runoff ◽  
History Of ◽  
Ice Conditions

The last glaciation of Fosheim Peninsula is reconstructed on the basis of landform and sediment mapping and associated radiocarbon dates. Ice growth involved the expansion of cirque glaciers and accumulation on upland surfaces that are now ice free. Limited ice buildup, despite lowering of the paleoglaciation level by 700–800 m, is attributed to the hyperaridity of the region during glacial conditions. Marine deposits in formerly submerged basins beyond the ice margins are interpreted to represent (i) sedimentation caused by local ice buildup and marine transgression by 10.6 ka BP, (ii) increased ablation and glacier runoff [Formula: see text]9.5 ka BP, and (iii) marine regression during the Holocene. Holocene marine limit reaches a maximum elevation of approximately 150 m asl along northern Eureka Sound and Greely Fiord and descends southeastwards to 139–142 m asl near the Sawtooth Mountains. A synchronous marine limit is implied where the last ice limit was inland of the sea. The magnitude and pattern of Holocene emergence cannot be fully explained by the glacioisostatic effects of the small ice load during the last glaciation of the region. Deglaciation of the peninsula was underway by 9.5 ka BP; however, local ice caps may have persisted through the wannest period of the Holocene until 6–5 ka BP. This was likely a function of reduced sea ice conditions and increased moisture availability which benefited low-lying coastal icefields, but had negligible effect on interior highland ice caps.

Human geographies of sea ice: freeze/thaw processes around Cape Dorset, Nunavut, Canada

Polar Record ◽  
2008 ◽  
Vol 44 (1) ◽  
pp. 51-76 ◽  
Author(s):  
Gita J. Laidler ◽  
Pootoogoo Elee
Keyword(s):  
Sea Ice ◽  
Regional Scale ◽  
Open Water ◽  
Current Strength ◽  
Ice Formation ◽  
Future Research ◽  
Baffin Island ◽  
Freeze Thaw ◽  
Ice Conditions ◽  
Inuit Knowledge

ABSTRACTSea ice has been, and continues to be, an integral component of life in the Inuit community of Cape Dorset, Nunavut. Located on an island of the same name off the southwestern coast of Baffin Island, the strong Hudson Strait currents prevent extensive ice formation around the community. Nevertheless, sea ice remains an important travel and hunting platform, enabling access to Baffin Island, hunting and fishing grounds, and nearby communities. With the combined importance, dynamism, and continuous use of this frozen ocean environment, local Inuit elders and hunters have developed a detailed and nuanced understanding of sea ice conditions, freeze/thaw processes, and the influences of winds and currents on ice conditions. Working collaboratively with the community of Cape Dorset since October, 2003, we present the results of 30 semi-directed interviews, 5 sea ice trips, and 2 focus groups to provide a baseline understanding of local freezing processes (near-shore, open water, sea ice thickening, landfast ice, floe edge, and tidal cracks), melting processes (snow melt, water accumulation and drainage, break-up, and cracks/leads), wind influences on sea ice (wind direction and strength affecting sea ice formation, and movement), and current influences on sea ice (tidal variations and current strength affecting sea ice formation, movement, and polynya size/location). Strong emphasis is placed on Inuktitut terminology and spatial delineations of localised ice conditions and features. Therefore, this paper provides insights into local scale ice conditions and dynamics around Cape Dorset that are not captured in regional scale studies of Hudson Bay and/or Hudson Strait. Results have the potential to inform future research efforts on local/regional sea ice monitoring, the relationship between Inuit knowledge, language, and the environment, and addressing community interests through targeted studies.

High Arctic sea ice conditions influence marine birds wintering in Low Arctic regions

2010 ◽  
Vol 89 (1) ◽  
pp. 97-106 ◽  
Author(s):  
Laura McFarlane Tranquilla ◽  
April Hedd ◽  
Chantelle Burke ◽  
William A. Montevecchi ◽  
Paul M. Regular ◽  
...  
Keyword(s):  
Sea Ice ◽  
High Arctic ◽  
Arctic Sea Ice ◽  
Marine Birds ◽  
Arctic Regions ◽  
Arctic Sea ◽  
Ice Conditions ◽  
Low Arctic

Late Quaternary Glacial History of the South Orkney Plateau, Antarctica

1990 ◽  
Vol 33 (3) ◽  
pp. 265-275 ◽  
Author(s):  
Margaret J. Herron ◽  
John B. Anderson
Keyword(s):  
Late Quaternary ◽  
The South ◽  
Ice Shelf ◽  
Radiocarbon Dates ◽  
Orkney Islands ◽  
Ice Cap ◽  
History Of ◽  
Seismic Records ◽  
Ice Conditions ◽  
History Of The South

AbstractPiston cores from the South Orkney Plateau penetrated overcompacted diamictons in water depths of up to 250 m. Detailed textural and petrological analyses of these diamictons indicate that they are basal tills. Seismic records from the plateau show a widespread surface of glacial erosion and provide additional evidence of an ice cap grounded to a depth of 250 m. Piston cores from the slope of the plateau penetrated diatomaceous muds resting directly on poorly sorted muds with very little to no biogenic material. The ice-rafted debris in these glacial-marine sediments is composed almost exclusively of material derived from the South Orkney Islands. This implies deposition beneath an ice shelf as opposed to iceberg rafting. In contrast, diatomaceous muds contain relatively abundant exotic iceberg-rafted material and reflect a glacial-maritime setting similar to that of today. The sharp contact separating diatomaceous surface sediments from basal tills and sub-ice shelf deposits indicates that the ice cap and ice shelf retreated from the plateau rapidly. Radiocarbon dates for diatomaceous muds from a glacial trough on the plateau indicate that the ice cap and ice shelf retreated from the plateau prior to 6000 to 7000 years ago. The homogeneity of surficial diatomaceous sediments suggests that sea ice conditions over the plateau have not changed radically since that time.

High Arctic Polynyas in a Changing Climate

2020 ◽  
Author(s):  
Rebecca Jackson ◽  
Anna Bang Kvorning ◽  
Christof Pearce ◽  
Marit-Solveig Seidenkrantz ◽  
Sofia Ribeiro
Keyword(s):  
Sea Ice ◽  
Indigenous Communities ◽  
High Arctic ◽  
Arctic Sea Ice ◽  
Holistic View ◽  
The Holocene ◽  
Changing Climate ◽  
New Findings ◽  
North Water ◽  
Ice Conditions

<p>Polynyas, areas of open water in the otherwise sea-ice dominated high Arctic, are vital oases for biological productivity, supporting a plethora of marine mammals and birds that in turn sustain indigenous communities. Polynyas are not, however, consistent features. Beyond the observational era, little to nothing is known about their past dynamics and equally, about their resilience to emerging changes in Arctic sea-ice conditions.</p><p>Recent paleoceanographic reconstructions of the North Water in northern Baffin Bay, the largest of the high Arctic polynyas, indicate that the polynya contracted in response to warm climatic intervals during the Holocene (e.g. Roman Warm Period). In contrast, the onset of stable North Water polynya formation acted to suppress northward incursion of warm Atlantic-sourced waters. This highlighted not only the sensitivity of polynyas to past climatic changes, but the role their formation plays in mediating water column dynamics and ocean circulation.</p><p>These new findings provided the rationale for the MSCA project ‘POLARC: High Arctic Polynyas in a Changing Climate’, to investigate the Holocene dynamics of other high Arctic polynyas forming off the east Greenland coast. New marine sedimentary archives and a multiproxy approach will be used to reconstruct productivity, sea-ice conditions and bottom water conditions, capturing a holistic view of these systems and their interaction with climatic and oceanographic variation during the Holocene (11,700 years BP to present). We present here preliminary paleoceanographic reconstructions of the Sirius Water, the first Holocene record from this polynya region, as well as plans for model-data comparisons in key polynya regions with the aim of constraining the past and better predicting the future of these phenomena.</p>

scholarly journals Holocene sedimentary environment of a High−Arctic fjord in Nordaustlandet, Svalbard

2014 ◽  
Vol 35 (1) ◽  
pp. 73-98 ◽  
Author(s):  
Antti E.K. Ojala ◽  
Veli−Pekka Salonen ◽  
Mateusz Moskalik ◽  
Frauke Kubischta ◽  
Markku Oinonen
Keyword(s):  
Sea Ice ◽  
Sedimentary Environment ◽  
High Arctic ◽  
Depositional History ◽  
Magnetic Parameters ◽  
Ice Conditions ◽  
Arctic Fjord ◽  
Climatic Optimum

AbstractA2.5−metrelong marine core from Isvika bay inNordaustlandet (80°N, 18°E) was AMS14C dated and analysed for its sedimentological and magnetic parameters. The studied record was found to cover the entire Holocene and indicates major turnovers in the palaeo− hydrography and sedimentary depositional history. The area was deglaciated at around 11,300 BP. The earlyHolocene has indications of rapidmelting of glaciers and frequent deposition of ice−rafted debris (IRD). The climatic optimum terminated with a probable glacier re−advance event occurring ca. 5800 cal BP. This event caused the deposition of a diamicton unit in Isvika bay, followed by a shift towards a colder and amore stratified hydrographic set− ting. The reduction in IRD indicates gradual cooling, which led to the stratification of the bay and eventually to more persistent fast sea−ice conditions by 2500 cal BP. For the last 500 years, Isvika has again been seasonally open.

scholarly journals Growth Rate and Salinity Profile of First-Year Sea Ice in the High Arctic

1981 ◽  
Vol 27 (96) ◽  
pp. 315-330 ◽  
Author(s):  
M. Nakawo ◽  
N. K Sinha
Keyword(s):  
Growth Rate ◽  
Sea Ice ◽  
Physical Properties ◽  
High Arctic ◽  
First Year ◽  
Baffin Island ◽  
Growth Season ◽  
Method Of Calculation ◽  
Salinity Profile ◽  
Snow Conditions

AbstractThis paper describes the growth of sea ice and the salinity profiles observed in Eclipse Sound near Pond Inlet, Baffin Island, Canada, during the winter of 1977–78. A numerical method of calculation has been developed to incorporate the variations in snow conditions and physical properties of ice and snow during the growth season. It is shown that the growth rate can be predicted reasonably well. It is also shown that the vertical salinity profile in the ice towards the end of the season, provides a record of previous climatological conditions. A dependence has been shown between the predicted growth rate and the measured salinity.

Late Quaternary paleoceanography and paleo-sea ice conditions in the Mackenzie Trough and Canyon, Beaufort SeaThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network.

2008 ◽  
Vol 45 (11) ◽  
pp. 1399-1415 ◽  
Author(s):  
Trecia M. Schell ◽  
David B. Scott ◽  
André Rochon ◽  
Steve Blasco
Keyword(s):  
Sea Ice ◽  
Saline Water ◽  
Late Quaternary ◽  
Laminated Sediments ◽  
Depth Range ◽  
Similar Time ◽  
Planktic Foraminifera ◽  
Climate Stability ◽  
Time Period ◽  
Ice Conditions

The Mackenzie Trough provides a high resolution signal for paleoceanography as a result of high sedimentation rates at the mouth of the Mackenzie River. Three cores were collected along a transect covering a depth range of 58–671 m and the time period of the last 11 500 cal BP. Prior to the last ∼10 000 cal BP, the distal core is characterized by laminated sediment and a foraminiferal fauna of Arctic Bottom Water calcareous species and abundant planktic foraminifera suggesting little freshwater runoff and (or) perennial sea-ice cover. This occurs at a similar time as laminated sediments from the west of this site, which have been suggested to be part of the Lake Agassiz flood outburst and (or) cold period. If this outburst occurred, the very positive oxygen isotope values from our core (PC3; >+3.0 ppm) indicate that it did not flow through the Mackenzie Trough. After 9000 cal BP, the faunas in the three cores differ because of timing and different water depths. However, it is possible to see a progression of cold saline water prior to 10 000 cal BP, with a freshening of surface water after 10 000 cal BP where tintinnids (brackish water ciliates) occur with incursions of deep water Arctic calcareous species to ∼3000 years BP. A sequence of mixed faunas appears as sea ice returns, at least periodically in the last 3000 cal BP; but (in core PC2 only) a return to more sea ice is recorded by both foraminifera and dinocysts in the last few hundred years.

scholarly journals Central Arctic Ocean paleoceanography from ~ 50 ka to present, on the basis of ostracode faunal assemblages from SWERUS 2014 expedition

2017 ◽  
Author(s):  
Laura Gemery ◽  
Thomas M. Cronin ◽  
Robert K. Poirier ◽  
Christof Pearce ◽  
Natalia Barrientos ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Large Scale ◽  
Late Quaternary ◽  
Atlantic Water ◽  
Environmental Indicators ◽  
The Arctic ◽  
Lomonosov Ridge ◽  
Central Arctic Ocean ◽  
Ice Conditions

Abstract. Late Quaternary paleoceanographic changes in the central Arctic Ocean were reconstructed from a multicore and gravity core from the Lomonosov Ridge (Arctic Ocean) collected during the 2014 SWERUS-C3 Expedition. Ostracode assemblages dated by accelerator mass spectrometry (AMS) indicate changing sea-ice conditions and warm Atlantic Water (AW) inflow to the Arctic Ocean from ~ 50 ka to present. Key taxa used as environmental indicators include Acetabulastoma arcticum (perennial sea ice), Polycope spp. (productivity and sea ice), Krithe hunti (partially sea-ice free conditions, deep water inflow), and Rabilimis mirabilis (high nutrient, AW inflow). Results indicate seasonally sea-ice free conditions during Marine Isotope Stage (MIS) 3 (~ 57–29 ka), rapid deglacial changes in water mass conditions (15–11 ka), seasonally sea-ice free conditions during the early Holocene (~ 10–7 ka) and perennial sea ice during the late Holocene. Comparisons with faunal records from other cores from the Mendeleev and Lomonosov Ridges suggest generally similar patterns, although sea-ice cover during the last glacial maximum may have been less extensive at the southern Lomonosov Ridge at our core site (~ 85.15° N, 152° E) than farther north and towards Greenland. The new data also provide evidence for abrupt, large-scale shifts in ostracode species depth and geographical distributions during rapid climatic transitions.

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