Schlüsselwörter
(Deutsch)
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space weather; space experiments; solar irradiance; terrestrial middle atmosphere
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Forschungsprogramme
(Englisch)
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COST-Action 724 - Developing the scientific basis for monitoring, modelling and predicting Space Weather
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Kurzbeschreibung
(Englisch)
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The influence of the Sun on the terrestrial climate is in the central focus of today's world-wide climate research. Three years ago, the NASA has started a project they termed 'Living With a Star' (LWS) and recently, the rest of the scientific world, including ESA, has joined in an international initiative called 'International Living With a Star' (ILWS). In a collaborative space experiment LYRA on board the PROBA2 satellite which will be lunched in 2006, the PMOD/WRC, together with Belgian Royal Observatory, will measure the solar UV irradiance in selected wavelength bands that are influencing directly the terrestrial atmosphere. In addition, continued monitoring of the UV radiation will be used to detect large solar explosions, such as Coronal Mass Ejections (CME) and therefore, the observations will also be used as warning trigger for possible particle impacts on Earth. In order to exploit the Swiss investments in hardware (Swiss PRODEX funds) we propose to the Swiss COST funds to support ½-post-doc position. The person will be responsible for collecting the data of the PROBA2/LYRA experiment, maintaining the data base web site, preparing the data for now-cast calculations, and interact in research with the other COST724 work packages. This position will be combined with ½-post doc position that has been granted by the SNF to the applicant. The part funded by the SNF will be responsible for now-casting space weather and atmospheric state as well as for theoretical studies of the atmospheric response to short-term solar variability.
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Weitere Hinweise und Angaben
(Englisch)
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Full name of research-institution/enterprise: Physikalisch-Meteorologisches Observatorium Davos Weltstrahlungszentrum Director PMOD /WRC
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Partner und Internationale Organisationen
(Englisch)
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AT, BE, BG, CH, CZ, DE, DK, ES, FI, FR, GR, HU, IE, IL, IT, NO, PL, RO, RS, SE, SI, SK, TR, UK
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Abstract
(Englisch)
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The solar UV irradiance and in particular, the solar Lyman-alpha emission, has a direct impact on the upper terrestrial atmosphere because it is a source of ionization for the D-region. It is the major contributor to the dissociation of atmospheric water vapor and other neutral atmospheric constituents and thus, it is a direct source of heat for the mesosphere. The LYRA experiment, which was developed by the PMOD/WRC in collaboration with the Royal Meteorological Observatory of Belgium will be launched on the ESA satellite PROBA2 in 2009. LYRA will monitor the solar irradiance at Lyman-alpha (121.6 nm) and in the Herzberg band (200-220 nm) wavelength range. Using the LYRA data, we will compute in near real time (i.e. 'nowcasting') the neutral and ionic state of the upper atmosphere. We intend to publish these results on a public European space weather internet site. Remark: The ESA space mission PROBA2 was origininally planned to be launched end of 2006. Several delays have shifted the launch of PROBA2 to early 2009. Therefore, it was not possible to deliver the nowcasting within the duration of the COST action 724 because of the missing the real time input to the model atmospheres. However, we intend to deliver the nowcasting as a Swiss contribution to the upcoming COST action ES0803, which is a continuation of the action 724. To accomplish the nowcasting project goal we developed a ion-chemistry module that was inserted into a coupled 3-D chemistry-ionosphere-climate model (CICM), which itself is an extension of the Coupled Climate Model SOCOL. SOCOL has been developed at PMOD/WRC as part of the ETH-Polyproject 'Variability of the Sun and Global Climate' (Egorova et al., 2005). We are limiting the ionospheric part of the model to the D-region between 50 and 90 km. We take into account ionization by direct solar radiation above 65 km and by galactic cosmic rays below 65 km. Modeling of the D-region differs from that of the upper E- and F-regions in that the D region has a rather complicated ion composition which is determined by the ion chemistry. We have defined and implemented a large list of chemical reactions and their rates for this region. The model is now ready for nowcasting as soon as data from LYRA/PROBA2 become available.
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Datenbankreferenzen
(Englisch)
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Swiss Database: COST-DB of the State Secretariat for Education and Research Hallwylstrasse 4 CH-3003 Berne, Switzerland Tel. +41 31 322 74 82 Swiss Project-Number: C04.0106
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