Browsing Geophysical Institute by Title

Now showing items 616-635 of 1292

    • Linking Sub-Tropical Evaporation and Extreme Precipitation Over East Antarctica: An Atmospheric River Case Study 

      Terpstra, Annick; Gorodetskaya, Irina V.; Sodemann, Harald (Journal article; Peer reviewed, 2021)
      We investigate an intense snowfall event between 15 and 18 February 2011 over the East Antarctic coastal region which contributed to roughly 24% of the annual snow accumulation. The event was previously associated with an ...

    • Local flow conditions in the Bergen valley based on observations and numerical simulations 

      Valved, Aslaug Skålevik (Master thesis, 2012-10-16)
      The complex topography and variability in surface roughness in the Bergen valley aff-ects the flow conditions in a multitude of ways. The steep mountains give shelter during strong synoptic flow, but the orography of Bergen ...

    • Local-scale deposition of surface snow on the Greenland ice sheet 

      Zuhr, Alexandra M.; Münch, Thomas; Steen-Larsen, Hans Christian; Hörhold, Maria; Laepple, Thomas (Journal article; Peer reviewed, 2021)
      Ice cores from polar ice sheets and glaciers are an important climate archive. Snow layers, consecutively deposited and buried, contain climatic information from the time of their formation. However, particularly ...

    • The Lofoten Basin Eddy: three years of evolution as observed by Seagliders 

      Yu, Lusha; Bosse, Anthony; Fer, Ilker; Orvik, Kjell Arild; Bruvik, Erik Magnus; Hessevik, Idar; Kvalsund, Karsten (Peer reviewed; Journal article, 2017-08)
      The Lofoten Basin in the Norwegian Sea is an area where the warm Atlantic Water is subject to the greatest heat losses anywhere in the Nordic Seas. A long-lived, deep, anticyclonic eddy is located in the central part of ...

    • Lofoten eddies observed by Seagliders 

      Løvseth, Hauk Morten (Master thesis, 2018-11-22)
      When the Norwegian Atlantic Current passes the Lofoten Basin, it loses a large amount of mass and heat to mesoscale eddies as a result of instabilities of the mean current along the Norwegian Slope. The eddies subsequently ...

    • Long term simulations of potential oil spills around Cuba 

      Hole, Lars Robert; Martins de Aguiar, Victor; Dagestad, Knut-Frode; Kourafalou, Vassiliki H.; Androulidakis, Yannis; Kang, Heesook; Le Hénaff, Matthieu; Calzada, Amilcar (Journal article; Peer reviewed, 2021)
      Simulations over eight years of continuous surface oil spills around Cuba are carried out to identify the most likely stranding (beaching) locations. The open source Lagrangian oil drift model OpenOil is applied with high ...

    • Long-term changes in the Nordic Seas' hydrographic structure and overflow waters 

      Breiteig, Øystein Markhus (Master thesis, 2020-06-30)
      A collection of historical hydrographic data was used to examine the hydrographic properties of the water masses in the Nordic Seas from 1950 to 2018, with particular focus on the dense overflows from the Nordic Seas. ...

    • Long-term intercomparison of two pCO2 instruments based on ship-of-opportunity measurements in a dynamic shelf sea environment 

      Macovei, Vlad A.; Voynova, Yoana G.; Becker, Meike; Triest, Jack; Petersen, Wilhelm (Journal article; Peer reviewed, 2021)
      The partial pressure of carbon dioxide (pCO2) in surface seawater is an important biogeochemical variable because, together with the pCO2 in the atmosphere, it determines the direction of air–sea carbon dioxide exchange. ...

    • Long-Term Retrospective Analysis of Mackerel Spawning in the North Sea: A New Time Series and Modeling Approach to CPR Data 

      Jansen, Teunis; Kristensen, Kasper; Payne, Mark; Edwards, Martin; Schrum, Corinna; Pitois, Sophie (Peer reviewed; Journal article, 2012-06-21)
      We present a unique view of mackerel (Scomber scombrus) in the North Sea based on a new time series of larvae caught by the Continuous Plankton Recorder (CPR) survey from 1948-2005, covering the period both before and after ...

    • Long-Term Statistics of Observed Bubble Depth Versus Modeled Wave Dissipation 

      Strand, Kjersti Opstad; Breivik, Øyvind; Pedersen, Geir; Vikebø, Frode Bendiksen; Sundby, Svein; Christensen, Kai Håkon (Journal article; Peer reviewed, 2020)
      Air bubble penetration depths are investigated with a bottom‐mounted echosounder at a seabed observatory in northern Norway. We compare a 1‐year time series of observed bubble depth against modeled and estimated turbulent ...

    • Long-term surface pCO2 trends from observations and models 

      Tjiputra, Jerry; Olsen, Are; Bopp, Laurent; Lenton, Andrew; Pfeil, Benjamin; Roy, Tilla; Segschneider, Joachim; Totterdell, Ian; Heinze, Christoph (Peer reviewed; Journal article, 2014-05-19)
      We estimate regional long-term surface ocean pCO2 growth rates using all available underway and bottled biogeochemistry data collected over the past four decades. These observed regional trends are compared with those ...

    • Long-term trends in surface ocean pH in the North Atlantic 

      Lauvset, Siv Kari; Gruber, Nicolas (Peer reviewed; Journal article, 2014-05)
      Presently available direct pH measurements do not have a sufficient data density in space or time in order to determine long-term trends across wider geographic regions, limiting our ability to assess the magnitude and ...

    • Long-term variability of dust events in Iceland (1949-2011) 

      Dagsson-Waldhauserova, Pavla; Arnalds, Olafur; Ólafsson, Haraldur (Peer reviewed; Journal article, 2014-12-16)
      The long-term frequency of atmospheric dust observations was investigated for the southern part of Iceland and interpreted together with earlier results obtained from northeastern (NE) Iceland (Dagsson-Waldhauserova et ...

    • Loop current variability as trigger of coherent gulf stream transport anomalies 

      Hirschi, Joël J.-M.; Frajka-Williams, Eleanor; Blaker, Adam T; Sinha, Bablu; Coward, Andrew; Hyder, Pat; Biastoch, Arne; Böning, Claus; Barnier, Bernard; Penduff, Thierry; Garcia, Ixetl; Fransner, Filippa; Madec, Gurvan (Journal article; Peer reviewed, 2019)
      Satellite observations and output from a high-resolution ocean model are used to investigate how the Loop Current in the Gulf of Mexico affects the Gulf Stream transport through the Florida Straits. We find that the expansion ...

    • Loss of sea ice during winter north of Svalbard 

      Onarheim, Ingrid Husøy; Smedsrud, Lars Henrik; Ingvaldsen, Randi; Nilsen, Frank (Peer reviewed; Journal article, 2014-06-05)
      Sea ice loss in the Arctic Ocean has up to now been strongest during summer. In contrast, the sea ice concentration north of Svalbard has experienced a larger decline during winter since 1979. The trend in winter ice area ...

    • Low Level Jet Streams at the Sea Ice Edge - Numerical Simulations using WRF 

      Keiderling, Stefan (Master thesis, 2013-06-03)
      The goal of the presented thesis is to investigate the formation of low level jets at the sea ice edge. Differential heating creates very sharp fronts at the ice edge. A transversal circulation, initiated by altered pressure ...

    • Low Level Jets over the Southern North Sea 

      Wagner, David; Steinfeld, Gerald; Witha, Björn; Wurps, Hauke; Reuder, Joachim (Peer reviewed; Journal article, 2019-12-02)
      An extensive analysis of Low Level Jets (LLJs) over the Southern North Sea is presented. The study is based on observational data from a wind LiDAR and a passive microwave radiometer, operated from May 2015 to October 2016 ...

    • A low-cost autonomous rover for polar science 

      Hoffman, Andrew; Christian Steen-Larsen, Hans; Christianson, Knut; Hvidberg, Christine (Peer reviewed; Journal article, 2019-06-11)
      We present the developmental considerations, design, and deployment of an autonomous modular terrestrial rover for ice-sheet exploration that is inexpensive, easy to construct, and allows for instrumentation customization. ...

    • Low-level jet height’s impact on wind turbine loads: A case study 

      Ahmed, Fahim Masud (Master thesis, 2023-06-01)
      Over the years, wind turbines have been steadily increasing in size, with newer models boasting larger dimensions. For instance, the diameter of an installed prototype offshore wind turbine in late 2022 was over 200 m, ...

    • The Madden-Julian Oscillation in a warmer world 

      Chang, Chiung-Wen June; Tseng, Wan-Ling; Huang-Hsiung, Hsu; Keenlyside, Noel; Tsuang, Ben-Jei (Peer reviewed; Journal article, 2015-07)
      Global warming's impact on the Madden-Julian Oscillation (MJO) is assessed using one of the few models capable in reproducing its key features. In a warmer climate predicted for the end of the century, the MJO increases ...