Isotopic Evidence for Relic Pleistocene Glacier Ice on Victoria Island, Canadian Arctic Archipelago

1985 ◽  
Vol 17 (1) ◽  
pp. 89 ◽  
Author(s):  
R. D. Lorrain ◽  
P. Demeur
2000 ◽  
Vol 37 (4) ◽  
pp. 601-619 ◽  
Author(s):  
Arthur S Dyke ◽  
James M Savelle

Some of the most extensive and massive end moraines of Younger Dryas age (11–10 14C ka BP) yet recognized in North America occur on Wollaston Peninsula of Victoria Island. On the western part of the peninsula, numerous closely spaced end moraines formed in the interval starting 11 100 ± 100 radiocarbon years ago and ending about 10 500–10 200 years ago. Net recession was generally slow throughout and was punctuated by moraine-building and at least two readvances. Recession is mapped with a resolution that is approximately decadal. The moraines form an orderly, nested succession and are consistently associated with westward shedding of meltwater, which formed a sequence of marine-limit deltas. We lack firm, independent proxy-climate evidence needed to assess whether these moraines formed because of cold Younger Dryas climate, rather than because of controls such as topographic setting and water depth, but climatic control seems probable. The moraines evidently retain glacier ice cores, as do most similarly large moraines in the Canadian Arctic Archipelago and northern mainland. They formed along active ice margins when the glacier mass balance on average was only slightly negative. Future melting of ice cores would produce regional hummocky moraine and much basal meltout till more than 10 000 years after deglaciation. Some southern areas of hummocky moraine may have originated as ice-cored moraines formed by active ice margins rather than from extensive regional stagnation.


2000 ◽  
Vol 54 (1) ◽  
pp. 113-120 ◽  
Author(s):  
Arthur S. Dyke ◽  
James M. Savelle

Holocene driftwood is found on postglacial raised beaches of Wollaston Peninsula, Victoria Island. The highest driftwood appears on the 12- to 13-m beach, which formed about 4000 yr B.P., and is common on beaches 12–6 m in elevation. The earliest Paleoeskimo dwelling features also occur on the 12- to 13-m beach. Wood increases on the 5- to 6-m beach, which formed about 2000 yr B.P., and is abundant below that level. Thus, zonation of wood suggests the following hypotheses: (1) that the coastal Mackenzie Current, the source of modern driftwood, did not operate before 4000 yr B.P. and lacked its present vigor or persistence until 2000 yr B.P.; and (2) that the apparent sudden influx of driftwood at 4000 yr B.P. may have provided a fuel resource and (or) may have been related to conditions that enabled first peopling. Radiocarbon ages indicate that (1) the first wood arrived about 4700 yr B.P.; (2) little wood arrived from 4700–2000 yr B.P.; and (3) influx of wood was episodic after 2000 yr B.P. Much of the wood that arrived after 1100 yr B.P. was redistributed by people and scattered on higher beaches. Explanation of the evident correlation between highest wood and highest dwelling features must await archaeological studies.


Rangifer ◽  
2014 ◽  
Vol 34 (1) ◽  
pp. 73 ◽  
Author(s):  
Keri McFarlane ◽  
Frank L. Miller ◽  
Samuel J. Barry ◽  
Gregory A. Wilson

We investigated the status of caribou classified as Rangifer tarandus pearyi by DNA analyses, with an emphasis on those large-bodied caribou identified as ultra pearyi that were collected in summer 1958 on Prince of Wales Island, south-central Canadian Arctic Archipelago. Our comparative assessment reveals that the ultra pearyi from Prince of Wales Island belong to a group of pearyi and are not hybrids of pearyi x groenlandicus, as we found for the caribou occurring on nearby Banks Island and northwest Victoria Island. The ultra pearyi from Prince of Wales Island cluster with high arctic pearyi and are separated genetically from the caribou populations that we sampled on the low Canadian Arctic Islands and the Canadian mainland. Our findings reveal biodiversity below the level of subspecies or regional designations. These results support the position that to retain the biodiversity present among caribou populations on the Canadian Arctic Islands, conservation efforts should be targeted at the smaller scale level of the geographic population, rather than on a wider regional or subspecific range-wide basis.


2014 ◽  
Vol 11 (2) ◽  
pp. 293-308 ◽  
Author(s):  
E. E. Popova ◽  
A. Yool ◽  
Y. Aksenov ◽  
A. C. Coward ◽  
T. R. Anderson

Abstract. The Arctic Ocean is a region that is particularly vulnerable to the impact of ocean acidification driven by rising atmospheric CO2, with potentially negative consequences for calcifying organisms such as coccolithophorids and foraminiferans. In this study, we use an ocean-only general circulation model, with embedded biogeochemistry and a comprehensive description of the ocean carbon cycle, to study the response of pH and saturation states of calcite and aragonite to rising atmospheric pCO2 and changing climate in the Arctic Ocean. Particular attention is paid to the strong regional variability within the Arctic, and, for comparison, simulation results are contrasted with those for the global ocean. Simulations were run to year 2099 using the RCP8.5 (an Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) scenario with the highest concentrations of atmospheric CO2). The separate impacts of the direct increase in atmospheric CO2 and indirect effects via impact of climate change (changing temperature, stratification, primary production and freshwater fluxes) were examined by undertaking two simulations, one with the full system and the other in which atmospheric CO2 was prevented from increasing beyond its preindustrial level (year 1860). Results indicate that the impact of climate change, and spatial heterogeneity thereof, plays a strong role in the declines in pH and carbonate saturation (Ω) seen in the Arctic. The central Arctic, Canadian Arctic Archipelago and Baffin Bay show greatest rates of acidification and Ω decline as a result of melting sea ice. In contrast, areas affected by Atlantic inflow including the Greenland Sea and outer shelves of the Barents, Kara and Laptev seas, had minimal decreases in pH and Ω because diminishing ice cover led to greater vertical mixing and primary production. As a consequence, the projected onset of undersaturation in respect to aragonite is highly variable regionally within the Arctic, occurring during the decade of 2000–2010 in the Siberian shelves and Canadian Arctic Archipelago, but as late as the 2080s in the Barents and Norwegian seas. We conclude that, for future projections of acidification and carbonate saturation state in the Arctic, regional variability is significant and needs to be adequately resolved, with particular emphasis on reliable projections of the rates of retreat of the sea ice, which are a major source of uncertainty.


1976 ◽  
Vol 16 (74) ◽  
pp. 119-133 ◽  
Author(s):  
Fritz Müller

AbstractThe 10 m temperatures were measured over several years at 16 sites on the White Glacier (lat. 80° N.), Axel Heiberg Island, Canadian Arctic Archipelago. At three sites deep profiles were made using a new drilling technique, reaching a maximum depth of 280 m. Large differences in the 10 m temperatures between locations and from year to year were observed. The deviations of these temperatures from the almost isothermal mean annual air temperature over the glacier are discussed. The heating effect of the melt water in the lower percolation zone was found to be very important. A conceptual model is developed to assess the influence of these irregularities in the energy input at the upper boundary on the thermal regime of the entire glacier. So far a quantitative analysis has been made only for the relatively simple 30 m temperature profile measured on the tongue of the glacier.


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