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Lilensten, Jean
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Lilensten, Jean
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- PublicationOpen AccessNowcasting, forecasting and warning for ionospheric propagation: supporting databases(2004)
; ; ; ;Stamper, R.; Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, U.K. ;Lilensten, J.; Laboratoire de Planétologie de Grenoble, Bâtiment D de Physique, Grenoble, France ;Jakowski, N.; Deutsches Zentrum für Luft und Raumfahrt (DLR), Institut für Kommunikation und Navigation (IKN),Neustrelitz, Germany; ; The use of data is essential in the context of nowcasting, forecasting and warning of ionospheric propagation conditions, with roles to play in the development, evaluation and operation of models and services. Descriptions are given of three databases that have been established in the course of the COST 271 Action: a database of prompt ionospheric soundings, an extension to a database generated by the EISCAT incoherent scatter radars, and a database intended to facilitate evaluation of TEC estimation methods. Each database includes some background information, a description of the contents and interface, and instructions as to how to gain access to it.183 164 - PublicationOpen AccessA revised method to extract thermospheric parameters from incoherent scatter observations(2004)
; ; ;Mikhailov, A. V.; Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (IZMIRAN), Russian Academy of Sciences, Troitsk (Moscow Region), Russia ;Lilensten, J.; Laboratoire de Planétologie de Grenoble, Bâtiment D de Physique, Grenoble, France; Height distribution of ionospheric plasma parameters in the F2-region is closely related to height distribution of the main thermospheric parameters. Therefore, they can be extracted from ionospheric observations solving an inverse problem of aeronomy. A self-consistent approach to the Ne(h) modeling at the F2-region heights has been applied to solve the problem. Using routine incoherent scatter radar observations (Ne(h), Te(h), Ti(h), Vi(h) profiles) the method yields a self-consistent set of main aeronomic parameters responsible for the F2-region formation. The list of derived parameters includes: neutral temperature profile Tn(h) depending on the exospheric temperature Tex, the temperature at 120 km T120 and the shape-parameter S, which determine the temperature profile, concentration of neutral species [O], [O2], [N2], vertical plasma drift W, which may be converted to the meridional thermospheric wind Vnx, total solar EUV flux and ion composition (O+, O2 +, NO+, N2 +, N+) as a result of Ne(h) fitting. Therefore, the method gives a complete description of the upper atmosphere condition in the vicinity of incoherent scatter facility for the periods of observation. Analysis of all available EISCAT (CP-1, CP-2) observations has shown wide deviations from MSIS-86 model predictions for geomagnetically disturbed conditions while the retrieved parameters are close to the model ones for quiet periods. The approach turns out to be very useful for physical analyses of the F2-layer disturbance mechanisms giving a complete picture of the phenomenon in question. Limitations and problems related to method application are discussed. Under existing conditions when thermospheric observations are not conducted currently the proposed method may be considered a real tool for thermosphere investigation and monitoring at least for the periods of ISR observations.203 467 - PublicationOpen AccessCollaboration between two COST actions. Ionosphere and space weather(2007)
; ; ; ; ; ;Lilensten, J.; Laboratoire de Planetologie de Grenoble, OSUG-CNRS, France ;Zolesi, B.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Belehaki, A.; National Observatory of Athens, Greece ;Stanislawska, I.; Polish Academy of Sciences, Space Research Center, Poland ;Perrone, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; ; ; ; In this paper, we describe the collaboration between two COST action: COST 724 devoted to space weather and COST 296 devoted to the study of the ionosphere and its impact on communication and positionning. Several colleagues work in the two actions. This resulted in an important input on ionospheric models provided by the COST 296 action to COST 724.221 233 - PublicationOpen AccessCollaboration among COST actions. Ionosphere and space weather(2008)
; ; ; ; ; ;Lilensten, J.; Laboratoire de Planétologie de Grenoble, OSUG-CNRS, France ;Zolesi, B.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Belehaki, A.; Ionospheric Group, Institute for Space Applications and Remote Sensing, National Observatory of Athens, Metaxa and Vas. Pavlou, 15236 Palaia Penteli, Greece ;Stanislawska, I.; Polish Academy of Sciences Space research center Bartycka 18 A 00 716 Warsaw Poland ;Perrone, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; ; ; ; ; ;The COST 724 Members ;The COST 724 Members; various Universities and InstitutesIn this paper, we describe the collaboration between two COST actions: COST 724 devoted to space weather and COST 296 (formerly COST 271) devoted to the study of the ionosphere and its impact on communication and positionning. Several colleagues work in the two actions. This resulted in an important input provided by the COST 296 action to COST 724 based on the ionospheric models developed during the last COST actions (COST 238, 251, 271 and 296) for space weather applications.202 714 - PublicationOpen AccessQuo vadis, European Space Weather community?(2021)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;This paper was written by a group of European researchers believing that now is the right time to frame the Space Weather and Space Climate discipline in Europe for future years. It is devoted to openly discussing the organisation and sustainability of the European Space Weather community and its assets in the (near) future. More specifically, we suggest that the European Space Weather community lacks a uniting organisation to help the community to sustain and develop the successful efforts made thus far. Our aim is not to draw a complete and exhaustive panorama of Space Weather throughout the world, nor even throughout Europe. It is not a new white paper on the science and applications: there exist many (e.g. Tsurutani BT et al. 2020. Nonlinear Processes Geophys 27(1): 75–119); nor another roadmap: several important have been published recently (e.g. Schrijver CJ et al. 2015. Adv Space Res 55(12): 2745– 2807; Opgenoorth HJ et al. 2019. J Space Weather Space Clim 9: A37). Our aim is to question our practices and organisation in front of several changes that have occurred in the recent years and to set the ground to provide coordinated answers to these questions being posed in Europe, and to make these answers discussed throughout the world. This group was assembled first through a series of sessions devoted to the sustainability of Space Weather research during the European Space Weather Week (ESWW) series of meetings, specifically: ESWW 14 (2017), ESWW 15 (2018), and ESWW 16 (2019). It then grew from discussions and personal contacts.111 30