Coordinated ground-based, low altitude satellite and Cluster observations on global and local scales during a transient post-noon sector excursion of the magnetospheric cusp

• Main Authors: Opgenoorth, H. J., Lockwood, M., Alcaydé, D., Donovan, E., Engebretson, M. J., van Eyken, A. P., Kauristie, K., Lester, M., Moen, J., Waterman, J., Alleyne, H., André, M., Dunlop, M. W., Cornilleau-Wehrlin, N., Masson, A., Fazerkerley, A., Rème, H., André, R., Amm, O., Balogh, A., Behlke, R., Blelly, P. L., Boholm, H., Borälv, E., Bosqued, J. M., Buchert, S., Candidi, M., Cerisier, J. C., Cully, C., Denig, W. F., Eglitis, P., Greenwald, R. A., Jackal, B., Kelly, J. D., Krauklis, I., Lu, G., Mann, I. R., Marcucci, M. F., Mccrea, I. W., Maksimovic, M., Massetti, S., Décréau, Pierrette, Milling, D. K., Orsini, S., Pitout, F., Provan, G., Ruohoniemi, J. M., Samson, J. C., Schott, J. J., Sedgemore-Schulthess, F., Stamper, R., Stauning, P., Strømme, A., Taylor, M., Vaivads, A., Villain, J. P., Voronkov, I., Wild, J. A., Wild, M.
• Other Authors: Swedish Institute of Space Physics Kiruna (IRF), Finnish Meteorological Institute (FMI), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy Calgary, University of Calgary, Department of Physics Minneapolis, Augsburg University Augsburg College Minneapolis, MN, USA, EISCAT Scientific Association Norway, University of Leicester, University of Oslo (UiO), Danish Meteorological Institute (DMI), University of Sheffield Sheffield, Imperial College London, Centre d'étude des environnements terrestre et planétaires (CETP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Space Research and Technology Centre (ESTEC), Agence Spatiale Européenne = European Space Agency (ESA), Mullard Space Science Laboratory (MSSL), University College of London London (UCL), Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy, Air Force Research Laboratory (AFRL), United States Air Force (USAF), Johns Hopkins University Applied Physics Laboratory Laurel, MD (APL), SRI International Menlo Park (SRI), National Center for Atmospheric Research Boulder (NCAR), University of York York, UK, Laboratoire de physique et chimie de l'environnement (LPCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), University of Alberta, Ecole et Observatoire des sciences de la terre (EOST), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Danish Space Research Institute (DSRI), University of Tromsø (UiT)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2001
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; EISCAT; Greenland; Svalbard
• Online Access: https://hal.science/hal-00329197; https://hal.science/hal-00329197/document; https://hal.science/hal-00329197/file/angeo-19-1367-2001.pdf

International audience On 14 January 2001, the four Cluster spacecraft passed through the northern magnetospheric mantle in close conjunction to the EISCAT Svalbard Radar (ESR) and approached the post-noon dayside magnetopause over Green-land between 13:00 and 14:00 UT. During that interval, a sudden reorganisation of the high-latitude dayside convection pattern occurred after 13:20 UT, most likely caused by a direction change of the Solar wind magnetic field. The result was an eastward and poleward directed flow-channel, as monitored by the SuperDARN radar network and also by arrays of ground-based magnetometers in Canada, Greenland and Scandinavia. After an initial eastward and later poleward expansion of the flow-channel between 13:20 and 13:40 UT, the four Cluster spacecraft, and the field line footprints covered by the eastward looking scan cycle of the Söndre Strömfjord incoherent scatter radar were engulfed by cusp-like precipitation with transient magnetic and electric field signatures. In addition, the EISCAT Svalbard Radar detected strong transient effects of the convection reorganisation, a poleward moving precipitation, and a fast ion flow-channel in association with the auroral structures that suddenly formed to the west and north of the radar. From a detailed analysis of the coordinated Cluster and ground-based data, it was found that this extraordinary transient convection pattern, indeed, had moved the cusp precipitation from its former pre-noon position into the late post-noon sector, allowing for the first and quite unexpected encounter of the cusp by the Cluster spacecraft. Our findings illustrate the large amplitude of cusp dynamics even in response to moderate solar wind forcing. The global ground-based data proves to be an invaluable tool to monitor the dynamics and width of the affected magnetospheric regions.