Latest Quaternary and Holocene paleoceanography of the eastern Baffin Island continental shelf, Canada: benthic foraminiferal evidence

1989 ◽  
Vol 26 (11) ◽  
pp. 2236-2248 ◽  
Author(s):  
Lisa E. Osterman ◽  
Alan R. Nelson
Keyword(s):  
Continental Shelf ◽  
The Arctic ◽  
Baffin Island ◽  
The South ◽  
Baffin Bay ◽  
The North ◽  
Postglacial History ◽  
Foraminiferal Species ◽  
Organic Sediment ◽  
Shelf Sediments

Foraminiferal zones, radiocarbon ages on shells, and corrected ages on pretreated organic sediment from four cores from the eastern Baffin Island continental shelf suggest a three-stage deglacial to postglacial history (Late Wisconsin to Holocene). The earliest sediments in the cores contain foraminiferal species (Elphidium excavatum, Cassidulina reniforme, Islandiella helenae) indicative of distal glaciomarine environments that lasted at least several thousand years. An oceanographic change about 8500 years ago is indicated by a Melonis zaandamae zone in northern and central shelf cores collected from 200–800 m water depth. The presence of M. zaandamae in the north and its absence in the south suggest warmer and more saline postglacial water in northern Baffin Bay, whose influence became diluted with cooler coastal meltwater as the current flowed south along the Baffin Island Shelf. Sediments after 6000 years ago on the northern and central shelf are dominated by agglutinated foraminifera, suggesting dissolution of calcareous species. This dissolution event, which affected deeper water cores sooner than cores from the shelf, may be related to the influx of cold, CO2-rich water from the Arctic Ocean during the mid-Holocene. Thus, postglacial oceanographic changes in Baffin Bay appear first in deep northern waters; the lag time in the response to these changes in the shallower water on the shelf and to the south may have been as long as several thousand years.

scholarly journals Holocene polynya dynamics and their interaction with oceanic heat transport in northernmost Baffin Bay

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rebecca Jackson ◽  
Anna Bang Kvorning ◽  
Audrey Limoges ◽  
Eleanor Georgiadis ◽  
Steffen M. Olsen ◽  
...  
Keyword(s):  
Sediment Cores ◽  
Active Role ◽  
Atlantic Water ◽  
The Arctic ◽  
Negative Consequences ◽  
Baffin Bay ◽  
The North ◽  
North Water ◽  
History Of ◽  
Ocean Conditions

AbstractBaffin Bay hosts the largest and most productive of the Arctic polynyas: the North Water (NOW). Despite its significance and active role in water mass formation, the history of the NOW beyond the observational era remains poorly known. We reconcile the previously unassessed relationship between long-term NOW dynamics and ocean conditions by applying a multiproxy approach to two marine sediment cores from the region that, together, span the Holocene. Declining influence of Atlantic Water in the NOW is coeval with regional records that indicate the inception of a strong and recurrent polynya from ~ 4400 yrs BP, in line with Neoglacial cooling. During warmer Holocene intervals such as the Roman Warm Period, a weaker NOW is evident, and its reduced capacity to influence bottom ocean conditions facilitated northward penetration of Atlantic Water. Future warming in the Arctic may have negative consequences for this vital biological oasis, with the potential knock-on effect of warm water penetration further north and intensified melt of the marine-terminating glaciers that flank the coast of northwest Greenland.

Radiogenic Isotope Signatures of Holocene Sediments from Kane Basin: Linkage with the Re-opening and Evolution of Nares Strait

2021 ◽  
Author(s):  
Lina Madaj ◽  
Friedrich Lucassen ◽  
Claude Hillaire-Marcel ◽  
Simone A. Kasemann
Keyword(s):  
Ellesmere Island ◽  
The Arctic ◽  
Baffin Bay ◽  
Low Salinity ◽  
The Core ◽  
The Past ◽  
Nares Strait ◽  
The North ◽  
Sediment Input ◽  
Detrital Sediment

<p>The re-opening of the Arctic Ocean-Baffin Bay gateway through Nares Strait, following the Last Glacial Maximum, has been partly documented, discussed and revised in the past decades. The Nares Strait opening has led to the inception of the modern fast circulation pattern carrying low-salinity Arctic water towards Baffin Bay and further towards the Labrador Sea. This low-salinity water impacts thermohaline conditions in the North Atlantic, thus the Atlantic Meridional Overturning Circulation. Available land-based and marine records set the complete opening between 9 and 7.5 ka BP [1-2], although the precise timing and intensification of the southward flowing currents is still open to debate. A recent study of a marine deglacial sedimentary record from Kane Basin, central Nares Strait, adds information about subsequent paleoceanographic conditions in this widened sector of the strait and proposed the complete opening at ~8.3 ka BP [3].</p><p>We present complementary radiogenic strontium, neodymium and lead isotope data of the siliciclastic detrital sediment fraction of this very record [3] further documenting the timing and pattern of Nares Strait opening from a sediment provenance approach. The data permit to distinguish detrital material from northern Greenland and Ellesmere Island, transported to the core location from both sides of Nares Strait. Throughout the Holocene, the evolution of contributions of these two sources hint to the timing of the ice break-up in Kennedy Channel, north of Kane Basin, which led to the complete opening of Nares Strait [3]. The newly established gateway of material transported to the core location from the north via Kennedy Channel is recorded by increased contribution of northern Ellesmere Island detrital sediment input. This shift from a Greenland (Inglefield Land) dominated sediment input to a northern Ellesmere Island dominated sediment input supports the hypothesis of the newly proposed timing of the complete opening of Nares Strait at 8.3 ka BP [3] and highlights a progressive trend towards modern-like conditions, reached at about 4 ka BP.</p><p>References:</p><p>[1] England (1999) Quaternary Science Reviews, 18(3), 421–456. [2] Jennings et al. (2011) Oceanography, 24(3), 26-41. [3] Georgiadis et al. (2018) Climate of the Past, 14 (12), 1991-2010.</p>

Hydrographic Changes in Nares Strait (Canadian Arctic Archipelago) in Recent Decades Based on δ18O Profiles of Bivalve Shells

ARCTIC ◽  
2011 ◽  
Vol 64 (1) ◽  
pp. 45 ◽  
Author(s):  
Marta E. Torres ◽  
Daniela Zima ◽  
Kelly K. Falkner ◽  
Robie W. Macdonald ◽  
Mary O'Brien ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
The Arctic ◽  
Past Century ◽  
Depth Range ◽  
Baffin Bay ◽  
Nares Strait ◽  
The North ◽  
The Arctic Ocean ◽  
Oxygen Isotopic ◽  
Bivalve Shells

<span style="font-family: 'Times New Roman';">Nares Strait is one of three main passages of the Canadian Archipelago that channel relatively fresh seawater from the Arctic Ocean through Baffin Bay to the Labrador Sea. Oxygen isotopic profiles along the growth axis of bivalve shells, collected live over the 5 – 30 m depth range from the Greenland and Ellesmere Island sides of the strait, were used to reconstruct changes in the hydrography of the region over the past century. The variability in oxygen isotope ratios is mainly attributed to variations in salinity and suggests that the northern end of Nares Strait has been experiencing an increase in freshwater runoff since the mid 1980s. The recent changes are most pronounced at the northern end of the strait and diminish toward the south, a pattern consistent with proximity to the apparently freshening Arctic Ocean source in the north and mixing with Baffin Bay waters as the water progresses southward. This increasing freshwater signal may reflect changes in circulation and ice formation that favor an increased flow of relatively fresh waters from the Arctic Ocean into Nares Strait. </span>

‘Take it from the top’: northern conceptions about identity in the western Arctic and beyond

Polar Record ◽  
2012 ◽  
Vol 48 (3) ◽  
pp. 222-229 ◽  
Author(s):  
Suzanne Robinson
Keyword(s):  
Northwest Territories ◽  
The Arctic ◽  
The South ◽  
Research Project ◽  
The North ◽  
The World ◽  
Western Arctic ◽  
Student Researchers

ABSTRACTDuring the last decades the Arctic has become more central on the world stage. However, despite increased interest how much do people really know about ‘the north’ and the ‘northern people’? The aim of this article is to chronicle a research project by students, who saw themselves as northerners, that used video to capture northerners’ definitions of the north, as well as asking the community about what they wanted newcomers and southern Canada to know about the north. The group also embarked on a new discipline of northerners studying ‘the south’. 43 students interviewed 95 people in the Beaufort Delta, Northwest Territories and 25 people in Edmonton, Alberta. The student researchers’ responses and that of their interviewees are some of the most direct messages on how northerners view their identity and that of their fellow southern Canadians. This project created a video tool to share, educate, and commence a dialogue between people about the north straight from the source.

scholarly journals The Middle Jurassic of western and northern Europe: its subdivisions, geochronology and correlations

2003 ◽  
Vol 1 ◽  
pp. 61-73 ◽  
Author(s):  
John H. Callomon
Keyword(s):  
North Sea ◽  
Middle Jurassic ◽  
The Arctic ◽  
The South ◽  
Temperate Latitude ◽  
The North ◽  
Biotic Diversity ◽  
The Pacific ◽  
Shelf Seas ◽  
Two Factors

The palaeogeographic settings of Denmark and East Greenland during the Middle Jurassic are outlined. They lay in the widespread epicontinental seas that covered much of Europe in the post-Triassic transgression. It was a period of continuing eustatic sea-level rise, with only distant connections to world oceans: to the Pacific, via the narrow Viking Straits between Greenland and Norway and hence the arctic Boreal Sea to the north; and to the subtropical Tethys, via some 1200 km of shelf-seas to the south. The sedimentary history of the region was strongly influenced by two factors: tectonism and climate. Two modes of tectonic movement governed basinal evolution: crustal extension leading to subsidence through rifting, such as in the Viking and Central Grabens of the North Sea; and subcrustal thermal upwelling, leading to domal uplift and the partition of marine basins through emergent physical barriers, as exemplified by the Central North Sea Dome with its associated volcanics. The climatic gradient across the 30º of temperate latitude spanned by the European seas governed biotic diversity and biogeography, finding expression in rock-forming biogenic carbonates that dominate sediments in the south and give way to largely siliciclastic sediments in the north. Geochronology of unrivalled finesse is provided by standard chronostratigraphy based on the biostratigraphy of ammonites. The Middle Jurassic saw the onset of considerable bioprovincial endemisms in these guide-fossils, making it necessary to construct parallel standard zonations for Boreal, Subboreal or NW European and Submediterranean Provinces, of which the NW European zonation provides the primary international standard. The current versions of these zonations are presented and reviewed.

scholarly journals Arctic Thunder: A Novel by R. Feagan

2011 ◽  
Vol 1 (1) ◽  
Author(s):  
Sandy Campbell
Keyword(s):  
Point Of View ◽  
The Arctic ◽  
The South ◽  
Traffic Light ◽  
Basketball Players ◽  
University Of Alberta ◽  
The North ◽  
Western Arctic ◽  
Turn Over ◽  
The University

Feagan, Robert. Arctic Thunder: A Novel. Toronto: Dundurn Press, 2010. Print. St. Albert is a small city, just north of Edmonton in Central Alberta.  In the opening pages of this book, thirteen-year-old Mike Watson and his team, the St. Albert Rams, win the Alberta Bantam Provincial box lacrosse championship.  Then his father, an RCMP officer, announces that they’ve been posted to Inuvik, which Mike describes as a place “somewhere inside the Arctic Circle and makes winter in St. Albert seem like summer”. The author, Robert Feagan, who lives in St. Albert, but spent much of his youth in RCMP posts across the Canadian Western Arctic, does a good job of presenting the struggles of a thirteen year old boy from the South trying to fit into the largely Inuit and Dene community in Inuvik. The story is definitely told from the point of view of a “white kid from the South”, except that Mike is part Zulu, so he sort of looks like he might fit in. Mike finds that teenagers are teenagers everywhere and when he goes to school he meets: the bully, the nerd whom everyone avoids and the super athletes, who in this case compete in the Arctic Games.  There is even a beautiful female nemesis, Gwen, who is one of the best basketball players Mike has every encountered. While well written and engaging, Feagan sometimes becomes a little didactic in educating the reader about the North.  Characters occasionally launch into unnaturally detailed explanations about things northern. Much of the tension between characters is also resolved too neatly.  Most of the core characters acquire self-understanding, turn over new leaves, and apologize to each other within a very few pages.  Much more realistic is the portrayal of the typical teenager, Mike, whispering a “Thank-you” to his Mom, long after she’s out of earshot. Through the course of the book, Mike (and the reader) come to appreciate what Inuvik, with its single traffic light and one retail store, has to offer.  Feagan works in a sensitive treatment of the role of the elders in the community and the healthy effects of living close to the land.  Of course, lacrosse, which no one plays in Inuvik, is an important thread through the story. Adult readers should not be put off by the fact that this is a young adult novel; it is a good Arctic read for anyone. Highly recommended: 4 out of 4 starsReviewer: Sandy Campbell Sandy is a Health Sciences Librarian at the University of Alberta, who has written hundreds of book reviews across many disciplines.  Sandy thinks that sharing books with children is one of the greatest gifts anyone can give. 

scholarly journals Biomarker characterization of the North Water Polynya, Baffin Bay: Implications for local sea ice and temperature proxies

2021 ◽  
Author(s):  
David J. Harning ◽  
Brooke Holman ◽  
Lineke Woelders ◽  
Anne E. Jennings ◽  
Julio Sepúlveda
Keyword(s):  
Sea Ice ◽  
The Arctic ◽  
Sea Ice Extent ◽  
Baffin Bay ◽  
The North ◽  
North Water Polynya ◽  
Lipid Biomarker ◽  
North Water ◽  
Order Of Magnitude ◽  
Insight Into

Abstract. The North Water Polynya (NOW, Greenlandic Inuit: Pikialasorsuaq), Baffin Bay, is the largest polynya and one of the most productive regions in the Arctic. This area of thin to absent sea ice is a critical moisture source for local ice sheet sustenance and coupled with the inflow of nutrient-rich Arctic Surface Water, supports a diverse community of Arctic fauna and indigenous people. Although paleoceanographic records can provide critical insight into the NOW’s past behavior, it is critical that we fully understand the modern functionality of the paleoceanographic proxies beforehand. In this study, we analyzed lipid biomarkers, including algal highly-branched isoprenoids and sterols for sea ice extent and pelagic productivity, and algal alkenones and archaeal GDGTs for ocean temperature, in a suite of modern surface sediment samples from within and around the NOW. Our data show that all highly-branched isoprenoids exhibit strong correlations with each other and show highest concentrations within the NOW, which suggests a spring/autumn sea ice diatom source rather than a combination of sea ice and open water diatoms as seen elsewhere in the Arctic. Sterols are also highly concentrated in the NOW and exhibit an order of magnitude higher concentration here compared to sites south of the NOW, consistent with the order of magnitude higher primary productivity observed within the NOW relative to surrounding waters in spring/summer months. Finally, our temperature calibrations for alkenones, GDGTs and OH-GDGTs reduce the uncertainty present in global temperature calibrations, but also identify some additional variables that may be important in controlling their local distribution, such as salinity, nutrients, and dissolved oxygen. Collectively, our datasets provide new insight into the utility of these lipid biomarker proxies in high-latitude settings and will help provide a refined perspective on the Holocene development of the NOW with their application in downcore reconstructions.

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