Search Results - "Laundal, K. M"

Quantifying the Mesoscale Contribution to FACs During a Magnetospheric Substorm by Gasparini, S., Kepko, L., Laundal, K. M.

“…Mesoscales, which couple small to large scales, and vice‐versa, are critical to the magnetosphere‐ionosphere coupling. Optical and radar measurements indicate…”
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Solar Wind and Seasonal Influence on Ionospheric Currents From Swarm and CHAMP Measurements by Laundal, K. M., Finlay, C. C., Olsen, N., Reistad, J. P.

“…We present a new climatological model of the ionospheric current system, determined from magnetic measurements taken by the Challenging Minisatellite Payload…”
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Substorm Impact on Dayside Ionospheric Currents by Elhawary, R., Laundal, K. M., Reistad, J. P., Madelaire, M., Ohma, A.

“…Ionospheric dayside dynamics is strongly controlled by the interaction between the Interplanetary Magnetic Field (IMF) and the Earth's magnetic field near the…”
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How the Ionosphere Responds Dynamically to Magnetospheric Forcing by Laundal, K. M., Hatch, S. M., Reistad, J. P., Ohma, A., Tenfjord, P., Madelaire, M.

“…Ground magnetic field variations have been used to investigate ionospheric dynamics for more than a century. They are usually explained in terms of an electric…”
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Possible Ionospheric Influence on Substorm Onset Location by Elhawary, R., Laundal, K. M., Reistad, J. P., Hatch, S. M.

“…Auroral substorm onset locations are highly unpredictable. Previous studies have shown that the By component of the interplanetary magnetic field (IMF)…”
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Magnetic Effects of Plasma Pressure Gradients in the Upper F Region by Laundal, K. M., Hatch, S. M., Moretto, T.

“…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…”
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Asymmetric auroral intensities in the Earth's Northern and Southern hemispheres by Laundal, K. M, Østgaard, N

“…It is commonly assumed that the aurora borealis (Northern Hemisphere) and aurora australis (Southern Hemisphere) are mirror images of each other because the…”
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Seasonal and Hemispheric Asymmetries of F Region Polar Cap Plasma Density: Swarm and CHAMP Observations by Hatch, S. M., Haaland, S., Laundal, K. M., Moretto, T., Yau, A. W., Bjoland, L., Reistad, J. P., Ohma, A., Oksavik, K.

“…One of the primary mechanisms of loss of Earth's atmosphere is the persistent “cold” ( T≲ 20 eV) ion outflow that has been observed in the magnetospheric lobes…”
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Evolution of IMF By Induced Asymmetries: The Role of Tail Reconnection by Ohma, A., Østgaard, N., Laundal, K. M., Reistad, J. P., Hatch, S. M., Tenfjord, P.

“…North‐south asymmetries arise in the magnetosphere‐ionosphere system when a significant east‐west (By) component is present in the interplanetary magnetic…”
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Evolution of Asymmetrically Displaced Footpoints During Substorms by Ohma, A., Østgaard, N., Reistad, J. P., Tenfjord, P., Laundal, K. M., Snekvik, K., Haaland, S. E., Fillingim, M. O.

“…It is well established that a transverse (y) component in the interplanetary magnetic field (IMF) induces a By component in the closed magnetosphere through…”
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Observations of Asymmetric Lobe Convection for Weak and Strong Tail Activity by Ohma, A., Østgaard, N., Reistad, J. P., Tenfjord, P., Laundal, K. M., Moretto Jørgensen, T., Haaland, S. E., Krcelic, P., Milan, S.

“…In this study we use high‐quality convection data from the Electron Drift Instrument on board Cluster to investigate how near‐Earth tail activity affects the…”
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Separation and Quantification of Ionospheric Convection Sources: 2. The Dipole Tilt Angle Influence on Reverse Convection Cells During Northward IMF by Reistad, J. P., Laundal, K. M., Østgaard, N., Ohma, A., Thomas, E. G., Haaland, S., Oksavik, K., Milan, S. E.

“…This paper investigates the influence of Earth's dipole tilt angle on the reverse convection cells (sometimes referred to as lobe cells) in the Northern…”
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The Relationship Between Cusp Region Ion Outflows and East‐West Magnetic Field Fluctuations at 4,000‐km Altitude by Hatch, S. M., Moretto, T., Lynch, K. A., Laundal, K. M., Gjerloev, J. W., Lund, E. J.

“…Abstract A number of interdependent conditions and processes contribute to ionospheric‐origin energetic ( 10 eV to several keV) ion outflows. Due to these…”
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Separation and Quantification of Ionospheric Convection Sources: 1. A New Technique by Reistad, J. P., Laundal, K. M., Østgaard, N., Ohma, A., Haaland, S., Oksavik, K., Milan, S. E.

“…This paper describes a novel technique that allows separation and quantification of different sources of convection in the high‐latitude ionosphere. To…”
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Interplanetary Magnetic Field Bx Component Influence on Horizontal and Field‐Aligned Currents in the Ionosphere by Laundal, K. M., Reistad, J. P., Finlay, C. C., Østgaard, N., Tenfjord, P., Snekvik, K., Ohma, A.

“…Statistical analyses have shown that the sunward component of the interplanetary magnetic field, Bx (Geocentric Solar Magnetospheric), moderately but…”
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The impact of sunlight on high‐latitude equivalent currents by Laundal, K. M., Gjerloev, J. W., Østgaard, N., Reistad, J. P., Haaland, S., Snekvik, K., Tenfjord, P., Ohtani, S., Milan, S. E.

“…Ground magnetic field measurements can be mathematically related to an overhead ionospheric equivalent current. In this study we look in detail at how the…”
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Dynamic effects of restoring footpoint symmetry on closed magnetic field lines by Reistad, J. P., Østgaard, N., Tenfjord, P., Laundal, K. M., Snekvik, K., Haaland, S., Milan, S. E., Oksavik, K., Frey, H. U., Grocott, A.

“…Here we present an event where simultaneous global imaging of the aurora from both hemispheres reveals a large longitudinal shift of the nightside aurora of…”
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Background removal from global auroral images: Data-driven dayglow modeling by Ohma, A., Madelaire, M., M. Laundal, K., P. Reistad, J., M. Hatch, S., Gasparini, S., J. Walker, S.

“…Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to…”
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Magnetic Coordinate Systems by Laundal, K. M., Richmond, A. D.

“…Geospace phenomena such as the aurora, plasma motion, ionospheric currents and associated magnetic field disturbances are highly organized by Earth’s main…”
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Evolution of auroral asymmetries in the conjugate hemispheres during two substorms by Østgaard, N., Humberset, B. K., Laundal, K. M.

“…Five hours of simultaneous global imaging data from the conjugate hemispheres are used to examine the dynamics of the auroral substorm. Earlier studies have…”
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