Blar i Bergen Open Research Archive på tidsskrift "Geophysical Research Letters"

Viser treff 21-40 av 95

    • The Direct Effect of Medium Energy Electron Precipitation on Mesospheric Dynamics During a Sudden Stratospheric Warming Event in 2010 

      Zuniga Lopez, Hector Daniel; Tyssøy, Hilde Nesse; Smith-Johnsen, Christine; Maliniemi, Ville Aleksi (Journal article; Peer reviewed, 2022)
      Medium energy electron (MEE) (30–1,000 keV) precipitation enhances the production of nitric (NOx) and hydrogen oxides (HOx) throughout the mesosphere, which can destroy ozone (O3) in catalytic reactions. The dynamical ...

    • Directed Network of Substorms Using SuperMAG Ground‐Based Magnetometer Data 

      Orr, L; Chapman, Sandra c.; Gjerløv, Jesper (Peer reviewed; Journal article, 2019)
      We quantify the spatiotemporal evolution of the substorm ionospheric current system utilizing the SuperMAG 100+ magnetometers. We construct dynamical directed networks from this data for the first time. If the canonical ...

    • Do the Throat Auroras Create Polar Cap Patches? 

      Zhang, Duan; Zhang, Qing-He; Oksavik, Kjellmar; Xu, Tong; Xing, Zan-Yang; Lyons, L.R.; Han, De-Sheng; Zhang, Hong-Bo; Ma, Yu-Zhang; Hu, Ze-Jun; Liu, Jian-Jun; Wang, Yong; Wang, Xiang-Yu (Journal article; Peer reviewed, 2023)
      Throat auroras and polar cap patches are common phenomena in the polar ionosphere resulting from magnetosphere-ionosphere coupling. A campaign was organized, with all-sky imagers at Yellow River Station, the European ...

    • Driving Mechanisms of an Extreme Winter Sea Ice Breakup Event in the Beaufort Sea 

      Davy, Richard; Olason, Einar; Rampal, Pierre; Spensberger, Clemens; Williams, Timothy; Korosov, Anton; Spengler, Thomas; Rheinlænder, Jonathan W. (Journal article; Peer reviewed, 2022)
      The thick multiyear sea ice that once covered large parts of the Arctic is increasingly being replaced by thinner and weaker first-year ice, making it more vulnerable to breakup by winds. We use the neXtSIM sea ice model ...

    • Early Holocene Temperature Oscillations Exceed Amplitude of Observed and Projected Warming in Svalbard Lakes 

      Bilt, Willem van der; D'Andrea, William J.; Werner, Johannes; Bakke, Jostein (Journal article; Peer reviewed, 2019)
      Arctic climate is uniquely sensitive to ongoing warming. The feedbacks that drive this amplified response remain insufficiently quantified and misrepresented in model scenarios of future warming. Comparison with paleotemperature ...

    • Electron Behavior Around the Onset of Magnetic Reconnection 

      Spinnangr, Susanne Flø; Hesse, Michael; Tenfjord, Paul Arne Riksheim; Norgren, Cecilia; Kolstø, Håkon Midthun; Kwagala, Norah Kaggwa; Jørgensen, Therese; Phan, Tai D. (Journal article; Peer reviewed, 2022)
      We investigate the onset of magnetic reconnection, utilizing a fully kinetic Particle-In-Cell (PIC) simulation. Characteristic features of the electron phase-space distributions immediately before reconnection onset are ...

    • Electron inflow velocities and reconnection rates at earth's magnetopause and magnetosheath 

      Burch, James L.; Webster, James M.; Hesse, Michael; Genestreti, Kevin J.; Denton, Richard E.; Phan, Tai D.; Hasegawa, Hiroshi; Cassak, Paul A.; Torbert, Roy B.; Giles, Barbara L.; Gershman, Daniel J.; Ergun, Robert E.; Russell, Christopher T.; Strangeway, Robert J.; Le Contel, Olivier; Pritchard, Kris R.; Marshall, Andrew T.; Hwang, Kyoung-Joo; Dokgo, Kyunghwan; Fuselier, Stephen A.; Chen, Li-Jen; Wang, Shan; Swisdak, Marc; Drake, James F.; Argall, Matthew R.; Trattner, Karlheinz J.; Yamada, Masaaki; Paschmann, Götz (Journal article; Peer reviewed, 2020)
      Electron inflow and outflow velocities during magnetic reconnection at and near the dayside magnetopause are measured using satellites from NASA's Magnetospheric Multiscale (MMS) mission. A case study is examined in detail, ...

    • Estimating the Rate of Cessation of Magnetospheric Activity in AMPERE Field‐Aligned Currents 

      Moretto, T; Hesse, Michael; Vennerstrøm, Susanne; Tenfjord, Paul (Peer reviewed; Journal article, 2018-12)
      The decay of magnetospheric activity when driving is turned off (to a minimum) was measured in total field‐aligned current estimates from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) ...

    • Eurasian Cooling Linked to the Vertical Distribution of Arctic Warming 

      He, Shengping; Xu, Xinping; Furevik, Tore; Gao, Yongqi (Journal article; Peer reviewed, 2020)
      Observations show that deep Arctic winter warming, extending from surface to mid‐troposphere, has concurred with below‐average temperature over central Eurasia. Modeling studies focusing on the response to Arctic sea ice ...

    • Evaluating Impacts of Recent Arctic Sea Ice Loss on the Northern Hemisphere Winter Climate Change 

      Ogawa, Fumiaki; Keenlyside, Noel; Gao, Yongqi; Koenigk, Torben; Yang, Shuting; Suo, Lingling; Wang, Tao; Gastineau, Guillaume; Nakamura, Tetsu; Cheung, Ho Nam; Omrani, Nour-Eddine; Ukita, Jinro; Semenov, Vladimir (Journal article; Peer reviewed, 2018)
      Wide disagreement among individual modeling studies has contributed to a debate on the role of recent sea ice loss in the Arctic amplification of global warming and the Siberian wintertime cooling trend. We perform coordinated ...

    • Exceptionally Warm and Prolonged Flow of Warm Deep Water Toward the Filchner‐Ronne Ice Shelf in 2017 

      Ryan, Svenja; Hellmer, Hartmut H.; Janout, Markus; Darelius, Elin Maria K.; Schröder, Michael; Vignes, Lucie (Journal article; Peer reviewed, 2020)
      The Filchner-Ronne Ice Shelf, fringing the southern Weddell Sea, is Antarctica's second largest ice shelf. At present, basal melt rates are low due to active dense water formation; however, model projections suggest a ...

    • An explicit IMF By dependence on solar wind ‐ magnetosphere coupling 

      Reistad, Jone Peter; Laundal, Karl Magnus; Ohma, Anders; Moretto, Therese; Milan, Steve (Peer reviewed; Journal article, 2019)
      Presently, all empirical coupling functions quantifying the solar wind—magnetosphere energy—or magnetic flux conversion assume that the coupling is independent of the sign of the dawn-dusk component (B𝑦) of the Interplanetary ...

    • Fate of Warm Pacific Water in the Arctic Basin 

      Lin, Peigen; Pickart, Robert S.; Våge, Kjetil; Li, Jianqiang (Journal article; Peer reviewed, 2021)
      Pacific Summer Water (PSW) plays a critical role in the ecosystem of the western Arctic Ocean, impacting sea-ice melt and providing freshwater to the basin. Most of the water exits the Chukchi Sea shelf through Barrow ...

    • Freshwater transport over the northeast Greenland shelf in Fram strait 

      Karpouzoglou, Theodoros; de Steur, Laura; Dodd, Paul (Journal article; Peer reviewed, 2023)
      We assess the contribution of flow over the Northeast Greenland Shelf (NEGS) to the total freshwater transport (FWT) through the Fram Strait. We analyze available observations since 2013 consisting of hydrographic sections, ...

    • Global Frequency and Geographical Distribution of Nighttime Streamer Corona Discharges (BLUEs) in Thunderclouds 

      Soler, S.; Gordillo-Vázquez, F.J.; Pérez-Invernón, F. J.; Luque, Alejandro; Li, D.; Neubert, Torsten; Chanrion, Olivier; Reglero, Victor; Navarro-Gonzalez, Javier; Østgaard, Nikolai (Journal article; Peer reviewed, 2021)
      Blue LUminous Events (BLUEs) are transient corona discharges occurring in thunderclouds and characterized by strong 337.0 nm light flashes with absent (or weak) 777.4 nm component. We present the first nighttime climatology ...

    • Global Recharge Data Set Indicates Strengthened Groundwater Connection to Surface Fluxes 

      Berghuijs, Wouter R.; Luijendijk, Elco; Moeck, Christian; van der Velde, Ype; Allen, Scott T. (Journal article; Peer reviewed, 2022)
      Groundwater is an invaluable global resource, but its long-term viability as a resource for consumption, agriculture, and ecosystems depends on precipitation recharging aquifers. How much precipitation recharges groundwaters ...

    • Hydrogen Relative Permeability Hysteresis in Underground Storage 

      Lysyy, Maksim; Fernø, Martin; Ersland, Geir (Journal article; Peer reviewed, 2022)
      Implementation of the hydrogen economy for emission reduction will require storage facilities, and underground hydrogen storage (UHS) in porous media offers a readily available large-scale option. Lack of studies on ...

    • Ice Thickness and Bed Elevation of the Northern and Southern Patagonian Icefields 

      Millan, Romain; Rignot, Eric; Rivera, A; Martineau, Vincent; Mouginot, Jérémie; Zamora, Rodrigo; Uribe, Jose; Lenzano, G; de Fleurian, Basile; Li, Xin; Gim, Yonggyu; Kirchner, Donald L. (Peer reviewed; Journal article, 2019)
      The Northern and Southern Patagonian Icefields are the largest ice masses in the Southern Hemisphere outside Antarctica, but their ice volume and bed topography are poorly known. Here, we combine airborne gravity data ...

    • Imaging Subduction Beneath Mount St. Helens: Implications for Slab Dehydration and Magma Transport 

      Mann, Michael E.; Abers, Geoffrey A.; Crosbie, Kayla; Creager, Kenneth; Ulberg, Carl; Moran, Seth; Rondenay, Stéphane (Peer reviewed; Journal article, 2019)
      Mount St. Helens (MSH) is anomalously 35–50 km trenchward of the main Cascade arc. To elucidate the source of this anomalous forearc volcanism, the teleseismic‐scattered wavefield is used to image beneath MSH with a dense ...

    • The Impact of Oxygen on the Reconnection Rate 

      Tenfjord, Paul; Hesse, Michael; Norgren, Astrid Elisabet Cecilia; Spinnangr, Susanne Flø; Kolstø, Håkon Midthun (Peer reviewed; Journal article, 2019-05-29)
      We investigate the role of a background oxygen population in magnetic reconnection, using particle‐in‐cell simulations. We run several simulations, with different initial oxygen temperatures and densities, to understand ...