Browsing Bergen Open Research Archive by Journals "Geophysical Research Letters"

Now showing items 41-60 of 95

    • Intensification of Near‐Surface Currents and Shear in the Eastern Arctic Ocean 

      Polyakov, Igor V.; Rippeth, Tom; Fer, Ilker; Baumann, Till Martin; Carmack, Eddy C.; Ivanov, Vladimir V.; Janout, Markus; Padman, Laurie; Pnyushkov, A.V.; Rember, Robert (Journal article; Peer reviewed, 2020)
      A 15‐year (2004–2018) record of mooring observations from the upper 50 m of the ocean in the eastern Eurasian Basin reveals increased current speeds and vertical shear, associated with an increasing coupling between wind, ...

    • Interferometric Study of Ionospheric Plasma Irregularities in Regions of Phase Scintillations and HF Backscatter 

      Spicher, Andres; LaBelle, James; Bonnell, John W.; Roglans, Roger; Moser, Chrystal; Fuselier, Stephen A.; Bounds, Scott; Clausen, Lasse; Di Mare, Francesca; Feltman, Connor A.; Jin, Yaqi; Kletzing, Craig; Miloch, Wojciech Jacek; Moen, Jøran Idar; Oksavik, Kjellmar; Sawyer, Rhyan; Takahashi, Toru; Yeoman, Tim K. (Journal article; Peer reviewed, 2022)
      We investigate the nature of small-scale irregularities observed in the cusp by the Twin Rockets to Investigate Cusp Electrodynamics-2 (TRICE-2) in regions of enhanced phase scintillations and high-frequency coherent radar ...

    • Intermittent Reduction in Ocean Heat Transport Into the Getz Ice Shelf Cavity During Strong Wind Events 

      Steiger, Nadine; Darelius, Elin; Wåhlin, Anna; Assmann, Karen Margarete (Journal article; Peer reviewed, 2021)
      The flow of warm water toward the western Getz Ice Shelf along the Siple Trough, West Antarctica, is intermittently disrupted during short events of Winter Water deepening. Here we show, using mooring records, that these ...

    • Investigating Fine‐Scale Permeability Structure and Its Control on Hydrothermal Activity Along a Fast‐Spreading Ridge (the East Pacific Rise, 9°43′–53′N) Using Seismic Velocity, Poroelastic Response, and Numerical Modeling 

      Marjanović, Milena; Barreyre, Thibaut; Fontaine, Fabrice; Escartín, Javier (Peer reviewed; Journal article, 2019)
      Along with the intracrustal heat source, crustal permeability is considered as the controlling factor for hydrothermal circulation within zero‐age oceanic crust. To obtain fine‐scale, 2‐D models of upper crustal permeability ...

    • Ion Behaviors in the Reconnection Diffusion Region of a Corrugated Magnetotail Current Sheet 

      Wang, Shan; Chen, Li-Jen; Bessho, Naoki; Hesse, Michael; Giles, Barbara L; Moore, Thomas E (Journal article; Peer reviewed, 2019)
      The current sheet structure and ion behaviors in a magnetotail reconnection diffusion region are investigated. The multispacecraft analysis suggests a corrugated current sheet structure, interpreted as due to a flapping ...

    • Laboratory Experiments on Internal Solitary Waves in Ice-Covered Waters 

      Carr, Magda; Sutherland, P.; Haase, A.; Evers, K.-U.; Fer, Ilker; Jensen, Atle; Kalisch, Henrik; Berntsen, Jarle; Parau, E.; Thiem, Ø.; Davies, P.A. (Peer reviewed; Journal article, 2019)
      Internal solitary waves (ISWs) propagating in a stably stratified two‐layer fluid in which the upper boundary condition changes from open water to ice are studied for grease, level, and nilas ice. The ISW‐induced current ...

    • Lagrangian Measurements of Orbital Velocities in the Surf Zone 

      Bjørnestad, Maria; Buckley, M.; Kalisch, Henrik; Streßer, M.; Horstmann, J.; Frøysa, Hege Guldbrandsen; Ige, Olufemi Elijah; Cysewski, M.; Carrasco-Alvarez, R. (Journal article; Peer reviewed, 2021)
      Eulerian and Lagrangian measurements of orbital velocities in waves approaching a beach are analyzed with the goal of understanding the relative influence of wave-by-wave variations in mean-water level, wave height and ...

    • Limited Influence of Localized Tropical Sea-Surface Temperatures on Moisture Transport into the Arctic 

      Dunn-Sigouin, Etienne; Li, Camille; Kushner, Paul J. (Journal article; Peer reviewed, 2021)
      Arctic moisture transport is dominated by planetary-scale waves in reanalysis. Planetary waves are influenced by localized Sea-Surface Temperature (SST) features such as the tropical warm pool. Here, an aquaplanet model ...

    • Magnetic Effects of Plasma Pressure Gradients in the Upper F Region 

      Laundal, Karl Magnus; Hatch, Spencer Mark; Moretto, Therese (Peer reviewed; Journal article, 2019)
      The Swarm satellites fly at altitudes that at polar latitudes are generally assumed to only contain currents that are aligned with the local magnetic field. Therefore, disturbances along the main field direction are mainly ...

    • Magnetic Reconnection in a Quasi-Parallel Shock: Two-Dimensional Local Particle-in-Cell Simulation 

      Bessho, Naoki; Chen, Lijen; Wang, Shan; Hesse, Michael; Wilson, Lynn B. (Peer reviewed; Journal article, 2019)
      Magnetic reconnection in a quasi‐parallel bow shock is investigated with two‐dimensional local particle‐in‐cell simulations. In the shock transition and downstream regions, large amplitude magnetic fluctuations exist, and ...

    • Magnetospheric Multiscale Observations of an Expanding Oxygen Wave in Magnetic Reconnection 

      Kolstø, Håkon Midthun; Norgren, Astrid Elisabet Cecilia; Hesse, Michael; Chen, Li-Jen; Tenfjord, Paul; Spinnangr, Susanne Flø; Kwagala, Norah Kaggwa (Journal article; Peer reviewed, 2021)
      Heavier plasma species such as oxygen ions can have a large impact on the magnetic reconnection process. It has been hypothesized that the acceleration of demagnetized oxygen ions by the Hall electric field will lead to ...

    • Marine-based multiproxy reconstruction of Atlantic multidecadal variability 

      Svendsen, Lea; Hetzinger, Steffen; Keenlyside, Noel; Gao, Yongqi (Peer reviewed; Journal article, 2014-02-28)
      Atlantic multidecadal variability (AMV) is known to impact climate globally, and knowledge about the persistence of AMV is important for understanding past and future climate variability, as well as modeling and assessing ...

    • Mass‐loading the Earth's dayside magnetopause boundary layer and its effect on magnetic reconnection 

      Fuselier, Stephen; Trattner, K.J.; Petrinec, Steve M.; Denton, Mike; Toledo, Sergio P.A.; Andrè, M.; Aunai, N; Chappell, Charles Richard; Glocer, Alex; Haaland, Stein; Hesse, Michael; Kistler, Lynn M.; Li, Wenya; Moore, T. E.; Graham, Daniel B.; Alm, Love; Tenfjord, Paul; Dargen, Jeremy; Vines, Sarah; Nykyri, K.; Burch, James L; Strangeway, Robert J. (Peer reviewed; Journal article, 2019)
      When the interplanetary magnetic field is northward for a period of time, O+ from the high‐latitude ionosphere escapes along reconnected magnetic field lines into the dayside magnetopause boundary layer. Dual‐lobe reconnection ...

    • Mean structure and seasonality of the Norwegian Atlantic Front Current along the Mohn Ridge from repeated glider transects 

      Bosse, Anthony; Fer, Ilker (Peer reviewed; Journal article, 2019)
      The poleward flow of Atlantic Water in the Nordic Seas forms the upper limb of the meridional overturning circulation driving an important heat transport. The Norwegian Atlantic Front Current along the Mohn Ridge between ...

    • Mechanisms underlying recent Arctic atlantification 

      Asbjørnsen, Helene; Årthun, Marius; Skagseth, Øystein; Eldevik, Tor (Journal article; Peer reviewed, 2020-06-20)
      Recent warming and reduced sea ice concentrations in the Atlantic sector of the Arctic Ocean are the main signatures of ongoing Arctic “Atlantification.” The mechanisms driving the warming trends are nevertheless still ...

    • The Micro-Macro Coupling of Mass-Loading in Symmetric Magnetic Reconnection With Cold Ions 

      Spinnangr, Susanne Flø; Hesse, Michael; Tenfjord, Paul Arne Riksheim; Norgren, Astrid Elisabet Cecilia; Kolstø, Håkon Midthun; Kwagala, Norah Kaggwa; Jørgensen, Therese Moretto (Journal article; Peer reviewed, 2021)
      We investigate how magnetic reconnection is influenced by an inflow of a dense cold ion population. We compare two 2.5D Particle-In-Cell simulations, one containing the cold population and one without. We find that the ...

    • MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets 

      Shuster, JR; Gershman, Daniel J; Chen, LJ; Wang, S; Bessho, Naoki; Dorelli, John C; da Silva, DE; Giles, Barbara L; Paterson, William R.; Denton, Richard E; Schwartz, S. J.; Norgren, Astrid Elisabet Cecilia; Wilder, F.D.; Cassak, P.A.; Swisdak, M; Uritsky, Vadim; Schiff, C.; Rager, AC; Smith, S; Avanov, LA; Vinas, AF (Journal article; Peer reviewed, 2019)
      We investigate the kinetic structure of electron‐scale current sheets found in the vicinity of the magnetopause and embedded in the magnetosheath within the reconnection exhaust. A new technique for computing terms of the ...

    • MMS Observations of Multiscale Hall Physics in the Magnetotail 

      Alm, Love; André, Mats; Graham, Daniel B.; Khotyaintsev, Yuri V.; Vaivads, Andris; Chappell, Charles Richard; Dargent, Jérémy; Fuselier, Stephen A.; Haaland, Stein; Lavraud, Benoit; Li, Wenya; Tenfjord, Paul; Toledo-Redondo, Sergio; Vines, Sarah K. (Journal article; Peer reviewed, 2019)
      We present Magnetospheric Multiscale mission (MMS) observations of Hall physics in the magnetotail, which compared to dayside Hall physics is a relatively unexplored topic. The plasma consists of electrons, moderately cold ...

    • Multi-Pulse Corona Discharges in Thunderclouds Observed in Optical and Radio Bands 

      Li, Dongshuai; Luque, Alejandro; Lehtinen, Nikolai Grigorievich; Gordillo-Vázquez, F.J.; Neubert, Torsten; Lu, Gaopeng; Chanrion, Olivier; Zhang, Hongbo; Østgaard, Nikolai; Reglero, Víctor (Journal article; Peer reviewed, 2022)
      How lightning initiates inside thunderclouds remains a major puzzle of atmospheric electricity. By monitoring optical emissions from thunderstorms, the Atmosphere-Space Interactions Monitor (ASIM) onboard the International ...

    • Necessary Conditions for Warm Inflow Toward the Filchner Ice Shelf, Weddell Sea 

      Daae, Kjersti; Hattermann, Tore; Darelius, Elin Maria K.; Mueller, Rachael D.; Naughten, Kaitlin A; Timmermann, Ralph; Hellmer, Hartmut H. (Journal article; Peer reviewed, 2020)
      Understanding changes in Antarctic ice shelf basal melting is a major challenge for predicting future sea level. Currently, warm Circumpolar Deep Water surrounding Antarctica has limited access to the Weddell Sea continental ...