Now showing items 1-20 of 59

    • Age characteristics of a shelf-break eddy in the western Arctic and implications for shelf-basin exchange 

      Kadko, David; Pickart, Robert S.; Mathis, Jeremy T. (American Geophysical Union, 2008-02-22)
      Radioisotope evaluation of a cold-core, anticyclonic eddy surveyed in September 2004 on the Chukchi Sea continental slope was used to determine its age since formation over the shelf environment. Because the eddy can be ...
    • The Arctic freshwater system : changes and impacts 

      White, Daniel; Hinzman, Larry; Alessa, Lilian; Cassano, John; Chambers, Molly; Falkner, Kelly; Francis, Jennifer; Gutowski, William J.; Holland, Marika M.; Holmes, Robert M.; Huntington, Henry; Kane, Douglas; Kliskey, Andrew; Lee, Craig M.; McClelland, James W.; Peterson, Bruce J.; Rupp, T. Scott; Straneo, Fiamma; Steele, Michael; Woodgate, Rebecca; Yang, Daqing; Yoshikawa, Kenji; Zhang, Tingjun (American Geophysical Union, 2007-11-20)
      Dramatic changes have been observed in the Arctic over the last century. Many of these involve the storage and cycling of fresh water. On land, precipitation and river discharge, lake abundance and size, glacier area and ...
    • Arctic Ocean basin liquid freshwater storage trend 1992–2012 

      Rabe, Benjamin; Karcher, Michael; Kauker, Frank; Schauer, Ursula; Toole, John M.; Krishfield, Richard A.; Pisarev, Sergey; Kikuchi, Takashi; Su, J. (John Wiley & Sons, 2014-02-12)
      Freshwater in the Arctic Ocean plays an important role in the regional ocean circulation, sea ice, and global climate. From salinity observed by a variety of platforms, we are able, for the first time, to estimate a ...
    • The Arctic Ocean spices up 

      Timmermans, Mary-Louise; Jayne, Steven R. (American Meteorological Society, 2016-04-05)
      The contemporary Arctic Ocean differs markedly from midlatitude, ice-free, and relatively warm oceans in the context of density-compensating temperature and salinity variations. These variations are invaluable tracers in ...
    • Arctic Ocean warming contributes to reduced polar ice cap 

      Polyakov, Igor V.; Timokhov, Leonid A.; Alexeev, Vladimir A.; Bacon, Sheldon; Dmitrenko, Igor A.; Fortier, Louis; Frolov, Ivan E.; Gascard, Jean-Claude; Hansen, Edmond; Ivanov, Vladimir V.; Laxon, Seymour W.; Mauritzen, Cecilie; Perovich, Donald K.; Shimada, Koji; Simmons, Harper L.; Sokolov, Vladimir T.; Steele, Michael; Toole, John M. (American Meteorological Society, 2010-12)
      Analysis of modern and historical observations demonstrates that the temperature of the intermediate-depth (150–900 m) Atlantic water (AW) of the Arctic Ocean has increased in recent decades. The AW warming has been uneven ...
    • An assessment of Arctic Ocean freshwater content changes from the 1990s to the 2006-2008 period 

      Rabe, Benjamin; Karcher, Michael; Schauer, Ursula; Toole, John M.; Krishfield, Richard A.; Pisarev, Sergey; Kauker, Frank; Gerdes, Rudiger; Kikuchi, Takashi (2010-12-10)
      Unprecedented summer-season sampling of the Arctic Ocean during the period 2006−2008 makes possible a quasi-synoptic estimate of liquid freshwater (LFW) inventories in the Arctic Ocean basins. In comparison to observations ...
    • Automated ice-tethered profilers for seawater observations under pack ice in all seasons 

      Krishfield, Richard A.; Toole, John M.; Proshutinsky, Andrey; Timmermans, Mary-Louise (American Meteorological Society, 2008-11)
      An automated, easily deployed Ice-Tethered Profiler (ITP) instrument system, developed for deployment on perennial sea ice in the polar oceans to measure changes in upper ocean water properties in all seasons, is described, ...
    • Baseline hearing abilities and variability in wild beluga whales (Delphinapterus leucas) 

      Castellote, Manuel; Mooney, T. Aran; Quakenbush, Lori T.; Hobbs, Roderick; Goertz, Caroline; Gaglione, Eric (2014-01)
      While hearing is the primary sensory modality for odontocetes, there are few data addressing variation within a natural population. This work describes the hearing ranges (4-150 kHz) and sensitivities of seven apparently ...
    • Biogeography of bacterioplankton in lakes and streams of an arctic tundra catchment 

      Crump, Byron C.; Adams, Heather E.; Hobbie, John E.; Kling, George W. (Ecological Society of America, 2007-06)
      Bacterioplankton community composition was compared across 10 lakes and 14 streams within the catchment of Toolik Lake, a tundra lake in Arctic Alaska, during seven surveys conducted over three years using denaturing ...
    • Bivalves as indicators of environmental variation and potential anthropogenic impacts in the southern Barents Sea 

      Carroll, Michael L.; Johnson, Beverly J.; Henkes, Gregory A.; McMahon, Kelton W.; Voronkov, Andrey; Ambrose, William G.; Denisenko, Stanislav G. (2009-04)
      Identifying patterns and drivers of natural variability in populations is necessary to gauge potential effects of climatic change and the expected increases in commercial activities in the Arctic on communities and ...
    • A conceptual model of an Arctic sea 

      St-Laurent, Pierre; Straneo, Fiamma; Barber, David G. (American Geophysical Union, 2012-06-20)
      We propose a conceptual model for an Arctic sea that is driven by river runoff, atmospheric fluxes, sea ice melt/growth, and winds. The model domain is divided into two areas, the interior and boundary regions, that are ...
    • Contrasting sensitivity to extreme winter warming events of dominant sub-Arctic heathland bryophyte and lichen species 

      Bjerke, Jarle W.; Bokhorst, Stef; Zielke, Matthias; Callaghan, Terry V.; Bowles, Francis W.; Phoenix, Gareth K. (2010-12)
      Climate change in northern high latitudes is predicted to be greater in winter rather than summer, yet little is known about the effects of winter climate change on northern ecosystems. Among the unknowns are the effects ...
    • Controls of benthic nitrogen fixation and primary production from nutrient enrichment of oligotrophic, Arctic lakes 

      Gettel, Gretchen M.; Giblin, Anne E.; Howarth, Robert W. (Springer, 2013-12-01)
      We examined controls of benthic dinitrogen (N2) fixation and primary production in oligotrophic lakes in Arctic Alaska, Toolik Field Station (Arctic Long-Term Ecological Research Site). Primary production in many oligotrophic ...
    • Detection and quantification of oil under sea ice : the view from below 

      Wilkinson, Jeremy P.; Boyd, Tim; Hagen, Bernard; Maksym, Ted; Pegau, Scott; Roman, Christopher N.; Singh, Hanumant; Zabilansky, Leonard (Elsevier, 2014-08-21)
      Traditional measures for detecting oil spills in the open-ocean are both difficult to apply and less effective in ice-covered seas. In view of the increasing levels of commercial activity in the Arctic, there is a growing ...
    • Distribution of Alexandrium fundyense (Dinophyceae) cysts in Greenland and Iceland, with an emphasis on viability and growth in the Arctic 

      Richlen, Mindy L.; Zielinski, Oliver; Holinde, Lars; Tillmann, Urban; Cembella, Allan D.; Lyu, Yihua; Anderson, Donald M. (2016-04)
      The bloom-forming dinoflagellate Alexandrium fundyense has been extensively studied due its toxin-producing capabilities and consequent impacts to human health and economies. This study investigated the prevalence of resting ...
    • Dynamics in the deep Canada Basin, Arctic Ocean, inferred by thermistor chain time series 

      Timmermans, Mary-Louise; Melling, Humfrey; Rainville, Luc (American Meteorological Society, 2007-04)
      A 50-day time series of high-resolution temperature in the deepest layers of the Canada Basin in the Arctic Ocean indicates that the deep Canada Basin is a dynamically active environment, not the quiet, stable basin often ...
    • Ecosystem feedbacks and cascade processes : understanding their role in the responses of Arctic and alpine ecosystems to environmental change 

      Wookey, Philip A.; Aerts, Rien; Bardgett, Richard D.; Baptist, Florence; Bråthen, Kari Anne; Cornelissen, Johannes H. C.; Gough, Laura; Hartley, Iain P.; Hopkins, David W.; Lavorel, Sandra; Shaver, Gaius R. (2008-09-11)
      Global environmental change, related to climate change and the deposition of airborne N-containing contaminants, has already resulted in shifts in plant community composition among plant functional types in arctic and ...
    • Eddies in the Canada Basin, Arctic Ocean, observed from ice-tethered profilers 

      Timmermans, Mary-Louise; Toole, John M.; Proshutinsky, Andrey; Krishfield, Richard A.; Plueddemann, Albert J. (American Meteorological Society, 2008-01)
      Five ice-tethered profilers (ITPs), deployed between 2004 and 2006, have provided detailed potential temperature θ and salinity S profiles from 21 anticyclonic eddy encounters in the central Canada Basin of the Arctic ...
    • Eddy transport of organic carbon and nutrients from the Chukchi Shelf : impact on the upper halocline of the western Arctic Ocean 

      Mathis, Jeremy T.; Pickart, Robert S.; Hansell, Dennis A.; Kadko, David; Bates, Nicholas R. (American Geophysical Union, 2007-05-04)
      In September 2004 a detailed physical and chemical survey was conducted on an anticyclonic, cold-core eddy located seaward of the Chukchi Shelf in the western Arctic Ocean. The eddy had a diameter of ∼16 km and was centered ...
    • Ekman veering, internal waves, and turbulence observed under Arctic sea ice 

      Cole, Sylvia T.; Timmermans, Mary-Louise; Toole, John M.; Krishfield, Richard A.; Thwaites, Fredrik T. (American Meteorological Society, 2014-05)
      The ice–ocean system is investigated on inertial to monthly time scales using winter 2009–10 observations from the first ice-tethered profiler (ITP) equipped with a velocity sensor (ITP-V). Fluctuations in surface winds, ...