The Holocene History of Nares Strait Transition from Glacial Bay to Arctic-Atlantic Throughflow
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Canadian Arctic Through-Flow 2012 Cruise to Nares Strait
Canadian Arctic Through-flow 2012 Cruise to Nares Strait CCGS Henry Larsen August 2-17, 2012 Institute of Ocean Sciences Cruise 2012-20 Humfrey Melling – Chief Scientist Fisheries & Oceans Canada Collaborating Institutions: Institute of Ocean Sciences, University of Delaware, Oxford University, Danish Technical University, Scottish Association for Marine Science 1 Cover photo, courtesy of Jason Box: View looking south across the Petermann ice shelf towards Joe Island, Kennedy Channel and Ellesmere Island at the horizon. Note the small ice-shelf fragments in the foreground and cracks within the protruding lobe of the ice . The photograph taken in 2009, before the large ice islands calved from the shelf in August 2010 and again in July 2012. 2 Report on the Scientific Cruise of CCGS Henry Larsen, August 2012 Canadian Arctic Through-flow CCGS Henry Larsen in Nares Strait August 2-17, 2012 Overview The Canadian Arctic Through-flow (CAT) study embodies ten years’ effort within Canada and the international community to measure flows of seawater and ice through the Canadian Archipelago, between the Arctic and the Atlantic Oceans. CATs is the outgrowth of a pilot effort, the Arctic Canada Watch, established in 1997. Moorings enabling year-round measurements were first placed in western Lancaster Sound and Cardigan Strait in 1998. These carried instruments to measure current, temperature and salinity and utilized innovations to address the unique challenges of observing: 1) current direction near the geomagnetic pole; 2) salinity within the hazardous 30-m zone beneath drifting ice pack. These early installations have been maintained and augmented since 1998. In 2003, a large array of instruments was installed across the third principal path for Canadian Arctic through-flow, Nares Strait. -
Matthew Henson (August 8, 1866 – March 9, 1955) “First African-American Artic Explorer”
The Clerk’s Black History Series Debra DeBerry Clerk of Superior Court DeKalb County Matthew Henson (August 8, 1866 – March 9, 1955) “First African-American Artic Explorer” Matthew Henson was born August 8, 1866, in Nanjemoy, Maryland, to freeborn black sharecropper parents. In 1867, his parents and three sisters moved to Georgetown to escape racial violence where his mother died when Matthew was seven years old. When Matthew’s father died, he went to live with his uncle in Washington, D.C. When Matthew was ten years old, he attended a ceremony honoring Abraham Lincoln where he heard social reformer and abolitionist, Frederick Douglas speak. Shortly thereafter, he left home, determined to find his own way. After working briefly in a restaurant, he walked all the way to Baltimore, Maryland. At the age of 12, Matthew went to sea as a cabin boy on the merchant ship Katie Hines, traveling to Asia, Africa and Europe under the watchful eye of the ship’s skipper, Captain Childs. After Captain Childs died, Matthew moved back to Washington, D.C. When Matthew was 21 years old, he met Commander Robert E. Peary, an explorer and officer in the U.S. Navy Corps of Civil Engineers. Impressed with Matthew’s seafaring experience, Commander Peary recruited him for an upcoming voyage to Nicaragua. After returning from Nicaragua, Matthew found work in Philadelphia, and in April 1891 he met and married Eva Flint. But shortly thereafter, the two explorers were off again for an expedition to Green- land and the marriage to Eva ended. Matthew and the Commander would cover thousands of miles across the sea and the world, exploring and making multiple attempts to reach the North Pole. -
Paleocene Alkaline Volcanism in the Nares Strait Region Related to Strike-Slip Tectonics
Paleocene Alkaline Volcanism in the Nares Strait Region Related to Strike-slip Tectonics Solveig Estrada & Detlef Damaske Federal Institute for Geosciences and Natural Resources (BGR), Hannover, Germany ([email protected]) The tectonic development of the North Atlantic, the Labrador Sea/Baffin Bay and the Eurasian Basin of Arctic Ocean led to relative movements between the Greenland Plate and the North American Plate. There has been a debate for many years, whether the Nares Strait between northwest Greenland and Ellesmere Island marks an ancient plate boundary in terms of a left-lateral transform fault (Wegener Fault) or whether there was no movement between Greenland and Ellesmere Island at all. New data were acquired during joint German-Canadian geological field work on northeast Ellesmere Island 1998-2000 (Mayr 2008), followed in 2001 by a geoscience cruise in Nares Strait (Tessensohn et al. 2006). Indications for sinistral strike-slip movements followed by compressive tectonics were found at the western margin of northern Nares Strait (Saalmann et al. 2005). Paleogene basins on Judge Daly Promontory, northeast Ellesmere Island, are bounded by a complex pattern of strike-slip and thrust faults. The clastic sediments in the basins are rich in volcanogenic material. Volcanic pebbles within the Cape Back basin near Nares Strait are derived from lava flows and ignimbrites of a continental rift-related, strongly differentiated, highly incompatible element enriched, alkaline volcanic suite (Estrada et al. 2009). 40Ar/39Ar amphibole and alkali feldspar ages indicate that volcanism was active around 61–58 Ma and was probably contemporaneous with sedimentation within the Paleogene pull-apart basins on Judge Daly Promontory formed by sinistral strike-slip tectonics parallel to the present-day Nares Strait. -
Twenty-First Century Response of Petermann Glacier, Northwest Greenland to Ice Shelf Loss
Journal of Glaciology Twenty-first century response of Petermann Glacier, northwest Greenland to ice shelf loss Emily A. Hill1* , G. Hilmar Gudmundsson2 , J. Rachel Carr1, Chris R. Stokes3 2 Article and Helen M. King 1 *Present address: Department of Geography School of Geography, Politics, and Sociology, Newcastle University, Newcastle-upon-Tyne, NE1 7RU, UK; and Environmental Sciences, Northumbria 2Department of Geography and Environmental Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, University, Newcastle-upon-Tyne, NE1 8ST, UK. UK and 3Department of Geography, Durham University, Durham, DH1 3LE, UK Cite this article: Hill EA, Gudmundsson GH, Carr JR, Stokes CR, King HM (2021). Twenty- Abstract first century response of Petermann Glacier, Ice shelves restrain flow from the Greenland and Antarctic ice sheets. Climate-ocean warming northwest Greenland to ice shelf loss. Journal could force thinning or collapse of floating ice shelves and subsequently accelerate flow, increase of Glaciology 67(261), 147–157. https://doi.org/ 10.1017/jog.2020.97 ice discharge and raise global mean sea levels. Petermann Glacier (PG), northwest Greenland, recently lost large sections of its ice shelf, but its response to total ice shelf loss in the future Received: 16 June 2020 remains uncertain. Here, we use the ice flow model Úa to assess the sensitivity of PG to changes Revised: 13 October 2020 in ice shelf extent, and to estimate the resultant loss of grounded ice and contribution to sea level Accepted: 14 October 2020 First published online: 2 December 2020 rise. Our results have shown that under several scenarios of ice shelf thinning and retreat, removal of the shelf will not contribute substantially to global mean sea level (<1 mm). -
Seismic Reflection Profiles from Kane to Hall Basin, Nares Strait: Evidence for Faulting
Polarforschung 74 (1-3), 21 – 39, 2004 (erschienen 2006) Seismic Reflection Profiles from Kane to Hall Basin, Nares Strait: Evidence for Faulting by H. Ruth Jackson1, Tim Hannon1, Sönke Neben2, Karsten Piepjohn2 and Tom Brent3 Abstract: Three major tectonic boundaries are predicted to be present beneath durch eine folgende kompressive Phase reaktiviert wurde. Als Arbeitshypo- the waters of this segment of Nares Strait: (1) the orogenic front of the Paleo- these fassen wir die oberflächennahen Teile dieses Systems als Stirn der Plat- zoic Ellesmerian Foldbelt between thrust sheets on Ellesmere Island and flat- tengrenze zwischen Nordamerika und Grönland auf. lying foreland rocks on Greenland, (2) the supposed sinistral strike-slip plate boundary of Paleocene age between the Ellemere Island section of the North America plate and the Greenland plate, and (3) the orogenic front of the Eocene to Oligocene Eurekan Foldbelt that must lie between thrust tectonics INTRODUCTION on Ellesmere Island and undeformed rocks of Greenland. To understand this complicated situation and to look for direct evidence of the plate boundary, The Late Cretaceous and Tertiary deformation on Ellesmere new seismic reflection profiles were collected and, together with industry data in the south, interpreted. The profiles are clustered in three areas controlled by Island (Fig. 1) called the Eurekan Orogeny has been attributed the distribution of the sea ice. Bathymetry is used to extrapolate seismic to the counter clockwise rotation of Greenland (e.g., OKULITCH features with a topographic expression between the regions. Based on high- & TRETTIN 1991). However reconciling the geology on oppo- resolution boomer and deeper penetration airgun profiles five seismic units are mapped. -
Chapter 8 Polar Bear Harvesting in Baffin Bay and Kane Basin: a Summary of Historical Harvest and Harvest Reporting, 1993 to 2014
Chapter 8 SWG Final Report CHAPTER 8 POLAR BEAR HARVESTING IN BAFFIN BAY AND KANE BASIN: A SUMMARY OF HISTORICAL HARVEST AND HARVEST REPORTING, 1993 TO 2014 KEY FINDINGS Both Canada (Nunavut) and Greenland harvest from the shared subpopulations of polar • bears in Baffin Bay and Kane Basin. During 1993-2005 (i.e., before quotas were introduced in Greenland) the combined • annual harvest averaged 165 polar bears (range: 120-268) from the Baffin Bay subpopulation and 12 polar bears (range: 6-26) from Kane Basin (for several of the years, harvest reported from Kane Basin was based on an estimate). During 2006-2014 the combined annual harvest averaged 161 (range: 138-176) from • Baffin Bay and 6 (range: 3-9) polar bears from Kane Basin. Total harvest peaked between 2002 and 2005 coinciding with several events in harvest • reporting and harvest management in both Canada and Greenland. In Baffin Bay the sex ratio of the combined harvest has remained around 2:1 (male: • females) with an annual mean of 35% females amongst independent bears. In Kane Basin the sex composition of the combined harvest was 33% females overall for • the period 1993-2014. The estimated composition of the harvest since the introduction of a quota in Greenland is 44% female but the factual basis for estimation of the sex ratio in the harvest is weak. In Greenland the vast majority of bears are harvested between January and June in Baffin • Bay and Kane Basin whereas in Nunavut ca. 40% of the harvest in Baffin Bay is in the summer to fall (August – November) while bears are on or near shore. -
High Arctic Holocene Temperature Record from the Agassiz Ice Cap and Greenland Ice Sheet Evolution
High Arctic Holocene temperature record from the Agassiz ice cap and Greenland ice sheet evolution Benoit S. Lecavaliera,1, David A. Fisherb, Glenn A. Milneb, Bo M. Vintherc, Lev Tarasova, Philippe Huybrechtsd, Denis Lacellee, Brittany Maine, James Zhengf, Jocelyne Bourgeoisg, and Arthur S. Dykeh,i aDepartment of Physics and Physical Oceanography, Memorial University, St. John’s, Canada, A1B 3X7; bDepartment of Earth and Environmental Sciences, University of Ottawa, Ottawa, Canada, K1N 6N5; cCentre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark, 2100; dEarth System Science and Departement Geografie, Vrije Universiteit Brussel, Brussels, Belgium, 1050; eDepartment of Geography, University of Ottawa, Ottawa, Canada, K1N 6N5; fGeological Survey of Canada, Natural Resources Canada, Ottawa, Canada, K1A 0E8; gConsorminex Inc., Gatineau, Canada, J8R 3Y3; hDepartment of Earth Sciences, Dalhousie University, Halifax, Canada, B3H 4R2; and iDepartment of Anthropology, McGill University, Montreal, Canada, H3A 2T7 Edited by Jeffrey P. Severinghaus, Scripps Institution of Oceanography, La Jolla, CA, and approved April 18, 2017 (received for review October 2, 2016) We present a revised and extended high Arctic air temperature leading the authors to adopt a spatially homogeneous change in reconstruction from a single proxy that spans the past ∼12,000 y air temperature across the region spanned by these two ice caps. 18 (up to 2009 CE). Our reconstruction from the Agassiz ice cap (Elles- By removing the temperature signal from the δ O record of mere Island, Canada) indicates an earlier and warmer Holocene other Greenland ice cores (Fig. 1A), the residual was used to thermal maximum with early Holocene temperatures that are estimate altitude changes of the ice surface through time. -
Seasonal Evolution of Supraglacial Lakes on a Floating Ice Tongue, Petermann Glacier, Greenland
Annals of Glaciology 59(76pt1) 2018 doi: 10.1017/aog.2018.9 56 © The Author(s) 2018. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons. org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. Seasonal evolution of supraglacial lakes on a floating ice tongue, Petermann Glacier, Greenland Grant J. MACDONALD,1 Alison F. BANWELL,2 Douglas R. MacAYEAL1 1Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637, USA. E-mail: [email protected] 2Scott Polar Research Institute, University of Cambridge, Lensfield Road, Cambridge, CB2 1ER, UK ABSTRACT. Supraglacial lakes are known to trigger Antarctic ice-shelf instability and break-up. However, to date, no study has focused on lakes on Greenland’s floating termini. Here, we apply lake boundary/area and depth algorithms to Landsat 8 imagery to analyse the inter- and intraseasonal evolu- tion of supraglacial lakes across Petermann Glacier’s (81°N) floating tongue from 2014 to 2016, while also comparing these lakes to those on the grounded ice. Lakes start to fill in June and quickly peak in total number, volume and area in late June/early July in response to increases in air temperatures. However, through July and August, total lake number, volume and area all decline, despite sustained high temperatures. These observations may be explained by the transportation of meltwater into the ocean by a river, and by lake drainage events on the floating tongue. Further, as mean lake depth remains relatively constant during this time, we suggest that a large proportion of the lakes that drain, do so completely, likely by rapid hydrofracture. -
PALEOLIMNOLOGICAL SURVEY of COMBUSTION PARTICLES from LAKES and PONDS in the EASTERN ARCTIC, NUNAVUT, CANADA an Exploratory Clas
A PALEOLIMNOLOGICAL SURVEY OF COMBUSTION PARTICLES FROM LAKES AND PONDS IN THE EASTERN ARCTIC, NUNAVUT, CANADA An Exploratory Classification, Inventory and Interpretation at Selected Sites NANCY COLLEEN DOUBLEDAY A thesis submitted to the Department of Biology in conformity with the requirements for the degree of Doctor of Philosophy Queen's University Kingston, Ontario, Canada December 1999 Copyright@ Nancy C. Doubleday, 1999 National Library Bibliothèque nationale 1*1 of Canada du Canada Acquisitions and Acquisitions et Bibf iographic Services services bibliographiques 395 Wellington Street 395. rue Wellington Ottawa ON KIA ON4 Ottawa ON K1A ON4 Canada Canada Your lYe Vorre réfhœ Our file Notre refdretua The author has granted a non- L'auteur a accordé une licence non exclusive licence allowing the exclusive pemettant à la National Library of Canada to Bibliothèque nationale du Canada de reproduce, Ioan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/nlm, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fiom it Ni la thèse ni des extraits substantiels may be printed or othemise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son pemission. autorisation. ABSTRACT Recently international attention has been directed to investigation of anthropogenic contaminants in various biotic and abiotic components of arctic ecosystems. Combustion of coai, biomass (charcoal), petroleum and waste play an important role in industrial emissions, and are associated with most hurnan activities. -
Research Cruise Report: Mission HLY031
Research Cruise Report: Mission HLY031 Conducted aboard USCGC Healy In Northern Baffi n Bay and Nares Strait 21 July –16 August 2003 Project Title: Variability and Forcing of Fluxes through Nares Strait and Jones Sound: A Freshwater Emphasis Sponsored by the US National Science Foundation, Offi ce of Polar Programs, Arctic Division Table of Contents Introduction by Chief Scientist . 4 Science Program Summary . 6 Science Party List . 7 Crew List . 8 Science Component Reports CTD-Rosette Hydrography . 9 Internally recording CTD . 29 Kennedy Channel Moorings . 33 Pressure Array . 41 Shipboard ADCP . 47 Bi-valve Retrieval . 51 Coring . 55 Seabeam Mapping . 65 Aviation Science Report . 71 Ice Report . 79 Weather Summary . 91 Inuit Perspective . 95 Photojournalist Perspective . 101. Website Log . 105 Chief Scientist Log . 111 Recommendations . .125 Introduction Dr. Kelly Kenison Falkner Chief Scientist Oregon State University In the very early hours of July 17, 2003, I arrived at collected via the ship’s Seabeam system and the underway the USCGC Healy moored at the fueling pier in St. John’s thermosalinograph system was put to good use throughout Newfoundland, Canada to assume my role as chief scientist much of the cruise. for an ambitious interdisciplinary mission to Northern Part of our success can be attributed to luck with Mother Baffi n Bay and Nares St. This research cruise constitutes Nature. Winds and ice worked largely in our favor as we the inaugural fi eld program of a fi ve year collaborative wound our way northward. Our winds were generally research program entitled Variability and Forcing of moderate and out of the south and the ice normal to light. -
Special Supplement to the Bulletin of the American Meteorological Society Vol
J. Blunden, D. S. Arndt, and M. O. Baringer, Eds. Associate Eds. K. M. Willett, A. J. Dolman, B. D. Hall, P. W. Thorne, J. M. Levy, H. J. Diamond, J. Richter-Menge, M. Jeffries, R. L. Fogt, L. A. Vincent, and J. M. Renwick Special Supplement to the Bulletin of the American Meteorological Society Vol. 92, No. 6, June 2011 www.whoi.edu/beaufort) show that the pack ice in the e. Land central Canada Basin is changing from a multiyear to 1) veGetation—D. A. Walker, U. S. Bhatt, T. V. Callaghan, J. a seasonal ice cover. C. Comiso, H. E. Epstein, B. C. Forbes, M. Gill, W. A. Gould, G. H. R. Henry, G. J. Jia, S. V. Kokelj, T. C. Lantz, S. F Oberbauer, 3) Sea ice thickness J. E. Pinzon, M. K. Raynolds, G. R. Shaver, C. J. Tucker, C. E. Combined estimates of ice thickness from sub- Tweedie, and P. J. Webber marine and satellite-based instruments provide the Circumpolar changes to tundra vegetation are longest record of sea ice thickness observation, begin- monitored from space using the Normalized Differ- ning in 1980 (Kwok et al. 2009; Ro throck et al. 2008). ence Vegetation Index (NDVI), an index of vegetation These data indicate that over a region covering ~38% greenness. In tundra regions, the annual maximum of the Arctic Ocean there is a long-term trend of sea NDVI (MaxNDVI) is usually achieved in early Au- ice thinning over the last three decades. gust and is correlated with above-ground biomass, Haas et al. -
Re-Evaluation of Strike-Slip Displacements Along and Bordering Nares Strait
Polarforschung 74 (1-3), 129 – 160, 2004 (erschienen 2006) In Search of the Wegener Fault: Re-Evaluation of Strike-Slip Displacements Along and Bordering Nares Strait by J. Christopher Harrison1 Abstract: A total of 28 geological-geophysical markers are identified that lich der Bache Peninsula und Linksseitenverschiebungen am Judge-Daly- relate to the question of strike slip motions along and bordering Nares Strait. Störungssystem (70 km) und schließlich die S-, später SW-gerichtete Eight of the twelve markers, located within the Phanerozoic orogen of Kompression des Sverdrup-Beckens (100 + 35 km). Die spätere Deformation Kennedy Channel – Robeson Channel region, permit between 65 and 75 km wird auf die Rotation (entgegen dem Uhrzeigersinn) und ausweichende West- of sinistral offset on the Judge Daly Fault System (JDFS). In contrast, eight of drift eines semi-rigiden nördlichen Ellesmere-Blocks während der Kollision nine markers located in Kane Basin, Smith Sound and northern Baffin Bay mit der Grönlandplatte zurückgeführt. indicate no lateral displacement at all. Especially convincing is evidence, presented by DAMASKE & OAKEY (2006), that at least one basic dyke of Neoproterozoic age extends across Smith Sound from Inglefield Land to inshore eastern Ellesmere Island without any recognizable strike slip offset. INTRODUCTION These results confirm that no major sinistral fault exists in southern Nares Strait. It is apparent to both earth scientists and the general public To account for the absence of a Wegener Fault in most parts of Nares Strait, that the shape of both coastlines and continental margins of the present paper would locate the late Paleocene-Eocene Greenland plate boundary on an interconnected system of faults that are 1) traced through western Greenland and eastern Arctic Canada provide for a Jones Sound in the south, 2) lie between the Eurekan Orogen and the Precam- satisfactory restoration of the opposing lands.