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The life history of the narwhal, Monodon monoceros l., in the eastern Canadian arctic /Hay, Keith Alexander. January 1984 (has links)
No description available.
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Adaptations of chaetognaths to subarctic conditionsNewbury, T. K. January 1971 (has links)
No description available.
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A geospatial analysis of Arctic marine trafficEucker, William January 2012 (has links)
Recent changes in Arctic Ocean climate dynamics and marine activity in the region require re-evaluation of physical operating conditions, ship traffic patterns, and policy requirements. This study used (1) government surveys, (2) vessel reports, and (3) Automatic Identification System (AIS) messages to characterize the spatial and temporal variability of surface vessel traffic in relation to various sea-ice conditions on the Arctic Ocean during a year-long study from 1 April 2010 to 31 March 2011. Data sources, methods of analysis, and errors were discussed. Three principal topics were examined. First, sea-ice cover on the Arctic Ocean was analysed to determine the physical access for marine operations. Daily sea-ice concentration data based on satellite passive microwave measurements were used to calculate the extent of open water and duration of the sea-ice season. Second, ship traffic on the Arctic Ocean was analysed to determine the present patterns of human activity. Time-stamped AIS messages encoded with Global Navigation Satellite System (GNSS) positions received by a commercial satellite constellation from north of the Arctic Circle (66·56°N) were used to calculate the distribution of vessels per unit area. Satellite AIS data from SpaceQuest, Limited, were compared with land-based vessel observations during the study period from the Marine Exchange of Alaska and the Port of Longyearbyen. Third, the spatial and temporal relationship between sea ice and surface vessels on the Arctic Ocean was analysed to determine potential policy implications. Three groups of marine operations with distinct characteristics were determined from the analysis: operations in perennial open water, operations in the seasonal ice zone, and operations in the perennial ice zone. Throughout the study year, most ships north of 66·56°N operated in perennially icefree areas, but year-round operations also occurred in ice-covered areas. The results from this study identify new pathways of information to enable consistent pan-Arctic assessment of physical operating conditions and ship traffic patterns. This approach provides novel considerations to sustainably develop a safe, secure, and environmentally protected Arctic Ocean.
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Environmental protection of the circumpolar arctic waters : A comparative study and an appraisal of the National Regulatory SystemsHarders, Johannes Enno January 1988 (has links)
Canada, the United States-Alaska, the Soviet Union-RSFSR, Norway, and Denmark/Greenland have non-specific laws apply for the environmental protection of their Arctic lands, waters, and marine spaces. But the piecemeal approaches employed neglect the need for environmentally sound management in respect of the multiple uses of the polar sea's delicate ecosystems. Convenient component elements of Arctic pollution are chosen for examination
-- (1) land-based sources of freshwater pollution and (2) marine-borne pollution resulting from offshore drilling and Arctic shipping. This comparative study moreover serves three objectives: (1) the exposition of the statutory instruments and administrative materials; (2) the evaluation of the national approaches taken for environmental protection generally and Arctic protection specifically; and (3) the appraisal of the accommodation and resolution of conflicts over interests concerning economic uses vis-a-vis environmental protection.
In the chapter on each state a background makes reference
to the national socio-legal and international legal conditions affecting municipal Arctic pollution control. The next section on the national regulatory framework follows the territorial and jurisdictional zones of the coastal state: from land-based operations affecting the freshwaters, to the coastal area, the body of law on shipping and navigation, the environmental provisions
of a 200 nautical mile exclusive economic zone, the continental shelf activities, to the regime on deep sea-bed mining. The latter of which ends this section and provides for the evaluation given in the concluding section on the country in question. The states have taken different avenues in their pollution control enactments: (1) blanket prohibition or the regulation of pollution; (2) the enforcement and supervision of statutory provisions; and/or (3) civil and criminal liability for violations of respective measures. Every state provides precedences for a number of recommendations
in order to facilitate resource uses, environmental
protection, and the integration of the Arctic natives in an ecosystem management approach to environmental protection. Examples are such like Norway's integrated statute on pollution prevention, the United States' legislation on coastal zone management and environmental impact assessments, and Canada's framework on Arctic shipping and Arctic pollution prevention. / Law, Peter A. Allard School of / Graduate
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Adaptations of chaetognaths to subarctic conditionsNewbury, T. K. January 1971 (has links)
No description available.
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Modelling carbon exchange in the air, sea, and ice of the Arctic OceanMortenson, Eric 03 June 2019 (has links)
The purpose of this study is to investigate the evolution of the Arctic Ocean’s carbon
uptake capacity and impacts on ocean acidification with the changing sea-ice scape. In
particular, I study the influence on air-ice-sea fluxes of carbon with two major updates to
commonly-used carbon cycle models I have included. One, incorporation of sea ice algae
to the ecosystem, and two, modification of the sea-ice carbon pump, to transport brineassociated
Dissolved Inorganic Carbon (DIC) and Total Alkalinity (TA) to the depth of
the bottom of the mixed layer (as opposed to releasing it in the surface model layer). I
developed the ice algal ecosystem model by adding a sympagic (ice-associated) ecosystem
into a 1D coupled sea ice-ocean model. The 1D model was applied to Resolute Passage in
the Canadian Arctic Archipelago and evaluated with observations from a field campaign
during the spring of 2010. I then implemented an inorganic carbon system into the model.
The carbon system includes effects on both DIC and TA due to the coupled ice-ocean
ecosystem, ikaite precipitation and dissolution, ice-air and air-sea carbon exchange, and
ice-sea DIC and TA exchange through a formulation for brine rejection to depth and
freshwater dilution associated with ice growth and melt. The 1D simulated ecosystem was
found to compare reasonably well with observations in terms of bloom onset and seasonal
progression for both the sympagic and pelagic algae. In addition, the inorganic carbon
system showed reasonable agreement between observations of upper water column DIC
and TA content. The simulated average ocean carbon uptake during the period of open
water was 10.2 mmol C m−2 day−1 ( 11 g C m−2 over the entire open-water season).
Using the developments from the 1D model, a 3D biogeochemical model of the Arctic Ocean
incorporating both sea ice and the water column was developed and tested, with a focus
on the pan-Arctic oceanic uptake of carbon in the recent era of Arctic sea ice decline (1980
– 2015). The model suggests the total uptake of carbon for the Arctic Ocean (north of
66.5 N) increases from 110 Tg C yr−1 in the early eighties (1980 – 1985) to 140 Tg C yr−1
for 2010 – 2015, an increase of 30%. The rise in SST accounts for 10% of the increase
in simulated pan-Arctic sea surface pCO2. A regional analysis indicated large variability
between regions, with the Laptev Sea exhibiting low sea surface pH relative to the pan-
Arctic domain mean and seasonal undersaturation of
arag by the end of the standard run. Two sensitivity studies were performed to assess the effects of sea-ice algae and the sea-ice carbon pump in the pan-Arctic, with a focus on sea surface inorganic carbon properties. Excluding the sea ice-carbon-pump showed a marked decrease in seasonal variability of sea-surface DIC and TA averaged over the Arctic Ocean compared to the standard run, but only a small change in the net total carbon uptake (of 1% by the end of the no icecarbon-pump run). Neglecting the sea ice algae, on the other hand, exhibits only a small change in sea-surface DIC and TA averaged over the pan-Arctic Ocean, but a cumulative effect on the net total carbon uptake of the Arctic Ocean (reaching 5% less than that of the standard run by the end of the no-ice-algae run). / Graduate
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The circulation and variability in the western Arctic Ocean : model results /Dixon, Jeffrey S. January 2003 (has links) (PDF)
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, September 2003. / Thesis advisor(s): Wieslaw Maslowski, Stephen Okkonen. Includes bibliographical references (p. 103-107). Also available online.
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Barium as a tracer of Arctic halocline and river watersGuay, Christopher K. H. 13 February 1997 (has links)
Graduation date: 1997
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Acoustic wave propagation in ice covered oceansSheard, John Daniel January 1994 (has links)
No description available.
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Determination of changes in the state of the Arctic ice pack using the NPS Pan-Arctic coupled ice-ocean modelMcNamara, Terry P. 03 1900 (has links)
This thesis provides an analysis of the diminishing sea ice trend in the Arctic Ocean by examining the NPS 1/12-degree pan-Arctic coupled ice-ocean model. While many previous studies have analyzed changes in ice extent and concentration, this research focuses on ice thickness as it gives a better indication of ice volume variability. The skill of the model is examined by comparing its output to sea ice thickness data gathered during the last two decades. The first dataset used is the collection of draft measurements conducted by U.S. Navy submarines between 1986 and 1999. The second is electromagnetic (EM) induction ice thickness measurements gathered using a helicopter by the Alfred Wegener Institute in April 2003. Last, model output is compared with data collected by NASAâ s ICESat program using a laser altimeter mounted on a satellite of the same name. The NPS model indicates an accelerated thinning trend in Arctic sea ice during the last decade. The validation of model output with submarine, EM and ICESat data supports this result. This lends credence to the postulation that the Arctic not only might, but is likely to be ice-free during the summer in the near future.
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