Browsing Bergen Open Research Archive by Author "Drange, Helge"

Now showing items 1-20 of 39

    • Annual carbon fluxes in the upper Greenland Sea based on measurements and a box-model approach 

      Anderson, Leif G.; Drange, Helge; Chierici, M.; Fransson, A.; Johannessen, Truls; Skjelvan, Ingunn; Rey, Francisco (Peer reviewed; Journal article, 2000-07)
      Measurements of nitrate and the carbonate system parameters performed mainly from 1993 to 1997 have been used to estimate the evolution of the concentration fields over the year in the surface and underlying waters of the ...

    • A brief history of climate – the northern seas from the Last Glacial Maximum to global warming 

      Eldevik, Tor; Risebrobakken, Bjørg; Bjune, Anne Elisabeth; Andersson, Carin; Birks, Harry John Betteley; Dokken, Trond Martin; Drange, Helge; Glessmer, Mirjam Sophia; Li, Camille; Nilsen, Jan Even Øie; Otterå, Odd Helge; Richter, Kristin; Skagseth, Øystein (Peer reviewed; Journal article, 2014-12)
      The understanding of climate and climate change is fundamentally concerned with two things: a well-defined and sufficiently complete climate record to be explained, for example of observed temperature, and a relevant ...

    • Data assimilation for coastal zone monitoring and forecasting 

      Evensen, Geir; Drange, Helge (Elsevier oceanography series. (EuroGOOS publication no. 7), Chapter, 1997)

    • Description and evaluation of the Bergen climate model: ARPEGE coupled with MICOM 

      Furevik, Tore; Bentsen, Mats; Drange, Helge; Kindem, I. K. T.; Kvamstø, Nils Gunnar; Sorteberg, Asgeir (Peer reviewed; Journal article, 2003-07)
      A new coupled atmosphere–ocean–sea ice model has been developed, named the Bergen Climate Model (BCM). It consists of the atmospheric model ARPEGE/IFS, together with a global version of the ocean model MICOM including a ...

    • Diagnosing and Understanding the AMOC Biases in NorESM 

      Ivanova, Detelina; Bentsen, Mats; Ilicak, Mehmet; Gao, Chuncheng; Drange, Helge (Conference poster, 2014)
      We investigate the Atlantic Meridional Overturning Circulation (AMOC) in the Norwegian Earth System Model (NorESM) featuring isopycnal ocean component (MICOM). The Coupled Model Intercomparison Phase 5 (CMIP5) NorESM ...

    • Diagnosing ocean tracer transport from Sellafield and Dounreay by equivalent diffusion and age 

      Orre, Steinar; Gao, Yongqi; Drange, Helge; Deleersnijder, Eric (Peer reviewed; Journal article, 2008-09-27)
      A simple approach for estimating the equivalent diffusion for diagnosing tracer transport is proposed. Two different expressions are derived; one is based directly on an analytical solution of the two-dimensional ...

    • Diapycnal Mixing in a Conceptual Model of the Atlantic Meridional Overturning Circulation 

      Marzeion, Ben; Drange, Helge (Journal article, 2006)
      A three-box model of the Atlantic Ocean is used to examine the influence different parameterisations of the diapycnal mixing may have on the large scale dynamics of the ocean circulation. Special emphasis is given to the ...

    • The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean 

      Gao, Yongqi; Drange, Helge (Advances in Atmospheric Sciences;21(5), Journal article, 2004-03-04)
      The Miami Isopycnic Coordinate Ocean Model (MICOM) is used to investigate the effect of diapycnal mixing on the oceanic uptake of CFC-11 and the ventilation of the surface waters in the Southern Ocean (south of 45°S). Three ...

    • Effects of diapycnal and isopycnal mixing on the ventilation of CFCs in the North Atlantic in an isopycnic coordinate OGCM 

      Gao, Yongqi; Drange, Helge; Bentsen, Mats (Peer reviewed; Journal article, 2003)
      Simulated distributions of the chlorofluorocarbons CFC-11 and CFC-12 are used to examine the ventilation of the North Atlantic Ocean in a global version of the Miami Isopycnic Coordinate Ocean Model (MICOM). Three simulations ...

    • Effects of simulated natural variability on Arctic temperature 

      Sorteberg, Asgeir; Furevik, Tore; Drange, Helge; Kvamstø, Nils Gunnar (Journal article, 2005-09-23)
      A five-member ensemble with a coupled atmospheresea ice-ocean model is used to examine the effects of natural variability on climate projections for the Arctic. The individual ensemble members are initialized from a 300 ...

    • Effects of solar irradiance forcing on the ocean circulation and sea-ice in the North Atlantic in an isopycnic coordinate ocean general circulation model 

      Otterå, Odd Helge; Drange, Helge (Peer reviewed; Journal article, 2004)
      The sensitivity of the ocean circulation to changes in solar irradiance is examined using an isopycnic coordinate, global ocean general circulation model (OGCM) coupled to a thermodynamic/dynamic sea-ice model. In the ...

    • Effects of solar irradiance forcing on the ocean circulation and sea-ice in the North Atlantic in an isopycnic coordinate ocean general circulation model 

      Otterå, Odd Helge; Drange, Helge (Tellus;56A(2), Journal article, 2004-03)
      The sensitivity of the ocean circulation to changes in solar irradiance is examined using an isopycnic coordinate, global ocean general circulation model (OGCM) coupled to a thermodynamic/dynamic sea-ice model. In the ...

    • Evaluating Global Ocean Carbon Models: The Importance of Realistic Physics 

      Doney, S. C.; Lindsay, K.; Caldeira, Ken; Campin, J. M.; Drange, Helge; Dutay, J. C.; Follows, M.; Gao, Yongqi; Gnanadesikan, A.; Gruber, N.; Ishida, A.; Joos, Fortunat; Madec, G.; Maier-Reimer, E.; Marshall, J. C.; Matear, R. J.; Monfray, P.; Mouchet, A.; Najjar, R.; Orr, J. C.; Plattner, G. K.; Sarmiento, J. L.; Schlitzer, R.; Slater, R.; Totterdell, I. J.; Weirig, M. F.; Yamanaka, Y.; Yool, A. (Peer reviewed; Journal article, 2004-09-15)
      A suite of standard ocean hydrographic and circulation metrics are applied to the equilibrium physical solutions from 13 global carbon models participating in phase 2 of the Ocean Carbon-cycle Model Intercomparison Project ...

    • Evaluation of ocean carbon cycle models with data-based metrics 

      Matsumoto, K.; Sarmiento, J. L.; Key, R. M.; Aumont, O.; Bullister, J. L.; Caldeira, Ken; Campin, J. M.; Doney, S. C.; Drange, Helge; Dutay, J. C.; Follows, M.; Gao, Yongqi; Gnanadesikan, A.; Gruber, N.; Ishida, A.; Joos, Fortunat; Lindsay, K.; Maier-Reimer, E.; Marshall, J. C.; Matear, R. J.; Monfray, P.; Mouchet, A.; Najjar, R.; Plattner, G. K.; Schlitzer, R.; Slater, R.; Swathi, P. S.; Totterdell, I. J.; Weirig, M. F.; Yamanaka, Y.; Yool, A.; Orr, J. C. (Journal article; Peer reviewed, 2004-04-02)
      New radiocarbon and chlorofluorocarbon-11 data from the World Ocean Circulation Experiment are used to assess a suite of 19 ocean carbon cycle models. We use the distributions and inventories of these tracers as quantitative ...

    • Future climate change: Modeling and scenarios for the Arctic 

      Kattsov, Vladimir M.; Källén, Erland; Cattle, Howard P.; Christensen, Jens; Drange, Helge; Hanssen-Bauer, Inger; Jóhannesen, Tómas; Karol, Igor; Räisänen, Jount; Svensson, Gunilla; Vavulin, Stanislav (Arctic Climate Impact Assessment (ACIA) Scientific Report;, Chapter, 2005-09)

    • Global and regional surface cooling in a warming climate: a multi-model analysis 

      Medhaug, Iselin; Drange, Helge (Peer reviewed; Journal article, 2015)
      Instrumental temperature records show that the global climate may experience decadal-scale periods without warming despite a long-term warming trend. We analysed 17 global climate models participating in phase 5 of the ...

    • Inception of the Northern European Ice Sheet due to contrasting ocean and insolation forcing 

      Risebrobakken, Bjørg; Dokken, Trond Martin; Otterå, Odd Helge; Jansen, Eystein; Gao, Yongqi; Drange, Helge (Peer reviewed; Journal article, 2007-01)
      About 115,000 years ago the last interglacial reached its terminus and nucleation of new ice sheet growth was initiated. Evidence from the northernmost Nordic Seas indicate that the inception of the last glacial was related ...

    • An intercomparison between the surface heat flux feedback in five coupled models, COADS and the NCEP reanalysis 

      Frankignoul, C.; Kestenare, E.; Botzet, M.; Carril, A. F.; Drange, Helge; Pardaens, A.; Terray, L.; Sutton, R. (Journal article; Peer reviewed, 2004-04)
      The surface heat flux feedback is estimated in the Atlantic and the extra-tropical Indo-Pacific, using monthly heat flux and sea surface temperature anomaly data from control simulations with five global climate models, ...

    • Last Glacial Maximum over China: Sensitivities of climate to paleovegetation and Tibetan ice sheet 

      Jiang, Dabang; Wang, Huijun; Drange, Helge; Lang, Xianmei (Journal article; Peer reviewed, 2003-02-06)
      With the boundary conditions appropriate for the Last Glacial Maximum (LGM), including ice sheets, sea surface temperatures, sea-ice distribution, atmospheric CO2 concentration, the Earth’s orbital parameters, topography, ...

    • Modeling the middle Pliocene climate with a global atmospheric general circulation model 

      Jiang, Dabang; Wang, Huijun; Ding, Zhongli; Lang, Xianmei; Drange, Helge (Peer reviewed; Journal article, 2005-07-27)
      A new climate simulation for the middle Pliocene (ca. 3 Ma BP) is performed by a global grid-point atmospheric general circulation model developed at the Institute of Atmospheric Physics (IAP AGCM) with boundary conditions ...