• On the Use of Dual Co-Polarized Radar Data to Derive a Sea Surface Doppler Model - Part 2: Simulation and Validation 

      Fan, Shengren; Zhang, Biao; Moiseev, Artem; Kudryavtsev, Vladimir; Johannessen, Johnny Andre; Chapron, Bertrand (Journal article; Peer reviewed, 2023)
      The Doppler shift obtained from synthetic aperture radar (SAR) measurements comprises the combined contribution to the radial motion of the ocean surface induced by the sea state (wind waves and swell) and underlying surface ...
    • On the utility of individual tendency output: Revealing interactions between parameterized processes during a marine cold air outbreak 

      Kähnert, Marvin; Sodemann, Harald; de Rooy, Wim; Valkonen, Teresa Maaria (Journal article; Peer reviewed, 2021)
      Forecasts of marine cold air outbreaks critically rely on the interplay of multiple parameterization schemes to represent subgrid-scale processes, including shallow convection, turbulence, and microphysics. Even though ...
    • One more step toward a warmer Arctic 

      Polyakov, Igor V.; Beszczynska-Möller, Agnieszka; Carmack, Eddy C.; Dmitreko, Igor A.; Fahrbach, E.; Frolov, Ivan E.; Gerdes, Rüdiger; Hansen, Edmond; Holfort, Jürgen; Ivanov, Vladimir V.; Johnson, Mark A.; Karcher, Michael; Kauker, Frank; Morison, James; Orvik, Kjell Arild; Schauer, Ursula; Simmons, Harper L.; Skagseth, Øystein; Sokolov, Vladimir T.; Steele, Michael; Timokhov, Leonid A.; Walsh, David; Walsh, John E. (Peer reviewed; Journal article, 2005-09-09)
      This study was motivated by a strong warming signal seen in mooring-based and oceanographic survey data collected in 2004 in the Eurasian Basin of the Arctic Ocean. The source of this and earlier Arctic Ocean changes lies ...
    • One-dimensional evolution of the upper water column in the Atlantic sector of the Arctic Ocean in winter 

      Fer, Ilker; Peterson, Algot Kristoffer; Randelhoff, Achim; Meyer, Amelie (Peer reviewed; Journal article, 2017-03)
      A one-dimensional model is employed to reproduce the observed time evolution of hydrographic properties in the upper water column during winter, between 26 January and 11 March 2015, in a region north of Svalbard in the ...
    • A one-year comparison of new wind atlases over the North Sea 

      Cheynet, Etienne; Solbrekke, Ida Marie; Diezel, Jan Markus; Reuder, Joachim (Journal article; Peer reviewed, 2022)
      The New European Wind Atlas (NEWA) and the Norwegian hindcast archive (NORA3) database have become publicly available since the end of 2019 and mid-2021, respectively. They aim to model the long-term wind climatology with ...
    • Open-source feature-tracking algorithm for sea ice drift retrieval from Sentinel-1 SAR imagery 

      Muckenhuber, Stefan; Korosov, Anton Andreevich; Sandven, Stein (Peer reviewed; Journal article, 2016-04-26)
      A computationally efficient, open-source feature-tracking algorithm, called ORB, is adopted and tuned for sea ice drift retrieval from Sentinel-1 SAR (Synthetic Aperture Radar) images. The most suitable setting and parameter ...
    • Open-source sea ice drift algorithm for Sentinel-1 SAR imagery using a combination of feature tracking and pattern matching 

      Muckenhuber, Stefan; Sandven, Stein (Peer reviewed; Journal article, 2017-08-07)
      An open-source sea ice drift algorithm for Sentinel-1 SAR imagery is introduced based on the combination of feature tracking and pattern matching. Feature tracking produces an initial drift estimate and limits the search ...
    • OpenDrift v1.0: A generic framework for trajectory modelling 

      Dagestad, Knut-Frode; Röhrs, Johannes; Breivik, Øyvind; Ådlandsvik, Bjørn (Peer reviewed; Journal article, 2018-04-13)
      OpenDrift is an open-source Python-based framework for Lagrangian particle modelling under development at the Norwegian Meteorological Institute with contributions from the wider scientific community. The framework is ...
    • Operational algorithm for ice–water classification on dual-polarized RADARSAT-2 images 

      Zakhvatkina, Natalia; Korosov, Anton; Muckenhuber, Stefan; Sandven, Stein; Babiker, Mohamed (Peer reviewed; Journal article, 2017-01-11)
      Synthetic Aperture Radar (SAR) data from RADARSAT-2 (RS2) in dual-polarization mode provide additional information for discriminating sea ice and open water compared to single-polarization data. We have developed an automatic ...
    • Optimization of the Offshore Wind Inter-Array Cable Layout problem using heuristic based algorithms 

      Fotedar, Sunney (Master thesis, 2018-06-13)
      The current work presents an in-exact solution method used to identify feasible, and less costly inter-array cable layout for offshore wind farms. The solution method developed has been built considering the interests of ...
    • Origin of moisture at Arctic sites 

      Jonassen, Trine (Master thesis, 2016-06-01)
      The hydrological cycle is an important component in the understanding of the climate system, and a good understanding of the moisture transport in the atmosphere is important in a changing climate. The climate change may ...
    • Overview of the MOSAiC expedition: Physical oceanography 

      Rabe, Benjamin; Baumann, Till Martin; Divine, Dmitry; Fer, Ilker; Gradinger, Rolf Rudolf; Granskog, Mats; Koenig, Zoe Charlotte; Muilwijk, Morven; Sundfjord, Arild (Journal article; Peer reviewed, 2022)
      Arctic Ocean properties and processes are highly relevant to the regional and global coupled climate system, yet still scarcely observed, especially in winter. Team OCEAN conducted a full year of physical oceanography ...
    • Overview of the Norwegian Earth System Model (NorESM2) and key climate response of CMIP6 DECK, historical, and scenario simulations 

      Seland, Øyvind; Bentsen, Mats; Oliviè, Dirk Jan Leo; Toniazzo, Thomas; Gjermundsen, Ada; Graff, Lise Seland; Debernard, Jens Boldingh; Gupta, Alok Kumar; He, Yan-Chun; Kirkevåg, Alf; Schwinger, Jörg; Tjiputra, Jerry; Aas, Kjetil Schanke; Bethke, Ingo; Fan, Yuanchao; Griesfeller, Jan; Grini, Alf; Guo, Chuncheng; Ilicak, Mehmet; Karset, Inger Helene H.; Landgren, Oskar Andreas; Liakka, Johan; Moseid, Kine Onsum; Nummelin, Aleksi; Spensberger, Clemens; Tang, Hui; Zhang, Zhongshi; Heinze, Christoph; Iversen, Trond; Schulz, Michael (Journal article; Peer reviewed, 2020-12)
      The second version of the coupled Norwegian Earth System Model (NorESM2) is presented and evaluated. NorESM2 is based on the second version of the Community Earth System Model (CESM2) and shares with CESM2 the computer ...
    • Overview of the PALM model system 6.0 

      Maronga, Bjørn; Banzhaf, Sabine; Burmeister, Cornelia; Esch, Thomas; Forkel, Renate; Fröhlich, Dominik; Fuka, Vladimir; Gehrke, Katrin Frieda; Geletič, Jan; Giersch, Sebastian; Gronemeier, Tobias; Groß, Günter; Heldens, Wieke; Hellsten, Antti; Hoffmann, Fabian; Inagaki, Atsushi; Kadasch, Eckhard; Kanani-Sühring, Farah; Ketelsen, Klaus; Ali Khan, Basit; Knigge, Christoph; Knoop, Helge; Krč, Pavel; Kurppa, Mona; Maamari, Halim; Matzarakis, Andreas; Mauder, Matthias; Pallasch, Matthias; Pavlik, Dirk; Pfafferott, Jens; Resler, Jaroslav; Rissmann, Sascha; Russo, Emmanuele; Salim, Mohamed; Schrempf, Michael; Schwenkel, Johannes; Seckmeyer, Gunther; Schubert, Sebastian; Sühring, Matthias; von Tils, Robert; Vollmer, Lukas; Ward, Simon; Witha, Björn; Wurps, Hauke; Zeidler, Julian; Raasch, Siegfried (Journal article; Peer reviewed, 2020)
      In this paper, we describe the PALM model system 6.0. PALM (formerly an abbreviation for Parallelized Large-eddy Simulation Model and now an independent name) is a Fortran-based code and has been applied for studying a ...
    • Ozone-induced climate change propped up by the Southern Hemisphere oceanic front 

      Ogawa, Fumiaki; Omrani, Nour-Eddine; Nishii, Kazuaki; Nakamura, Hisashi; Keenlyside, Noel (Peer reviewed; Journal article, 2015-11-23)
      The late twentieth century was marked by a significant summertime trend in the Southern Annular Mode (SAM), the dominant mode of tropospheric variability in the extratropical Southern Hemisphere (SH). This trend with ...
    • Pacific circulation response to eastern Arctic sea ice reduction in seasonal forecast simulations 

      Seidenglanz, Anne; Athanasiadis, Panos J.; Ruggieri, Paolo; Cvijanovic, Ivana; Li, Camille; Gualdi, Silvio (Journal article; Peer reviewed, 2021)
      Recent studies point to the sensitivity of mid-latitude winter climate to Arctic sea ice variability. However, there remain contradictory results in terms of character and timing of Northern Hemisphere large-scale circulation ...
    • Pacific contribution to decadal surface temperature trends in the Arctic during the twentieth century 

      Svendsen, Lea; Keenlyside, Noel; Muilwijk, Morven; Bethke, Ingo; Omrani, Nour-Eddine; Gao, Yongqi (Journal article; Peer reviewed, 2021)
      Instrumental records suggest multidecadal variability in Arctic surface temperature throughout the twentieth century. This variability is caused by a combination of external forcing and internal variability, but their ...
    • Pacific contribution to the early twentieth-century warming in the Arctic 

      Svendsen, Lea; Keenlyside, Noel; Bethke, Ingo; Gao, Yongqi; Omrani, Nour-Eddine (Journal article; Peer reviewed, 2018)
      Arctic surface temperature warmed more than twice as fast as global temperature during the early twentieth century, similar to that during the recent global warming. This Arctic warming has been attributed to both external ...
    • Pacific oceanic front amplifies the impact of Atlantic oceanic front on North Atlantic blocking 

      Cheung, Ho Nam; Omrani, Nour-Eddine; Ogawa, Fumiaki; Keenlyside, Noel Sebastian; Nakamura, Hisashi; Zhou, Wen (Journal article; Peer reviewed, 2023)
      Atmospheric blocking is a crucial driver of extreme weather events, but its climatological frequency is largely underestimated in state-of-the-art climate models, especially around the North Atlantic. While air-sea interaction ...
    • Pan-Atlantic decadal climate oscillation linked to ocean circulation 

      Nnamchi, Hyacinth C.; Farneti, Riccardo; Keenlyside, Noel Sebastian; Kucharski, Fred; Latif, Mojib; Reintges, Annika; Martin, Thomas (Journal article; Peer reviewed, 2023)
      Atlantic climate displays an oscillatory mode at a period of 10–15 years described as pan-Atlantic decadal oscillation. Prevailing theories on the mode are based on thermodynamic air-sea interactions and the role of ocean ...