ENHANCED GLOBAL NUCLEAR EVENT LOCATION AND ITS UNCERTAINTY ANALYSIS BASED ON VARIOUS ADJOINT ENSEMBLE DISPERSION MODELLING TECHNIQUES

After the detection of treaty-relevant radionuclides in filters or air samples, atmospheric backtracking techniques are employed by the Provisional Technical Secretariat (PTS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) to trace back the measured substances to their potential areas of origin. In the case of an underground nuclear test, potential sources are co-located with the epicentres of seismic events that may have been triggered by the explosions. Previous studies have shown that predictions or analyses of atmospheric transport can be significantly improved by ensemble techniques. Within the CTBT environment it is important to build confidence in the source-receptor sensitivity (SRS) field based backtracking products issued by the PTS in the case of the occurrence of treaty relevant radionuclides. Therefore the PTS has set up a highly automated response system together with the Regional Specialized Meteorological Centres of the World Meteorological Organization in the field of dispersion modelling. These Centres have committed themselves to provide the PTS with the same standard SRS fields as calculated by their systems for CTBT relevant cases. The SRS field data standard allows for ensemble dispersion modelling. The parametric inter-comparison among ensemble members has been integrated into the decision making software tool WEB-GRAPE (CTBTO Newsletter Spectrum, 7, page 19). In sensitivity studies we varied the choice of LPDM, and the kind and source of wind field utilized to demonstrate the potential of the following two ensemble dispersion modelling (EDM) methods: a) Multi-model EDM in order to improve the accuracy of a global scale source attribution based on joint CTBTO-WMO experiments in January 2005 (Becker et al., 2007) and December 2007 (Wotawa and Becker, 2008). b) Single-model EDM with different lead times of the wind fields utilized in order to estimate the relative error of forecasted source attribution results in comparison to the analyzed ones c) Single-model EDM with different choices of wind field resolutions for the source receptor sensitivity fields of the same station at Schauinsland in order to assess quality of the PTS standard backtracking results based on the rather coarse 1º×1º horizontal resolution

ENHANCED GLOBAL NUCLEAR EVENT LOCATION AND ITS UNCERTAINTY ANALYSIS BASED ON VARIOUS ADJOINT ENSEMBLE DISPERSION MODELLING TECHNIQUES

After the detection of treaty-relevant radionuclides in filters or air samples, atmospheric backtracking techniques are employed by the Provisional Technical Secretariat (PTS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) to trace back the measured substances to their potential areas of origin. In the case of an underground nuclear test, potential sources are co-located with the epicentres of seismic events that may have been triggered by the explosions. Previous studies have shown that predictions or analyses of atmospheric transport can be significantly improved by ensemble techniques. Within the CTBT environment it is important to build confidence in the source-receptor sensitivity (SRS) field based backtracking products issued by the PTS in the case of the occurrence of treaty relevant radionuclides. Therefore the PTS has set up a highly automated response system together with the Regional Specialized Meteorological Centres of the World Meteorological Organization in the field of dispersion modelling. These Centres have committed themselves to provide the PTS with the same standard SRS fields as calculated by their systems for CTBT relevant cases. The SRS field data standard allows for ensemble dispersion modelling. The parametric inter-comparison among ensemble members has been integrated into the decision making software tool WEB-GRAPE (CTBTO Newsletter Spectrum, 7, page 19). In sensitivity studies we varied the choice of LPDM, and the kind and source of wind field utilized to demonstrate the potential of the following two ensemble dispersion modelling (EDM) methods: a) Multi-model EDM in order to improve the accuracy of a global scale source attribution based on joint CTBTO-WMO experiments in January 2005 (Becker et al., 2007) and December 2007 (Wotawa and Becker, 2008). b) Single-model EDM with different lead times of the wind fields utilized in order to estimate the relative error of forecasted source attribution results in comparison to the analyzed ones c) Single-model EDM with different choices of wind field resolutions for the source receptor sensitivity fields of the same station at Schauinsland in order to assess quality of the PTS standard backtracking results based on the rather coarse 1º×1º horizontal resolution

Estimation of the time-dependent radioactive source-term from the Fukushima nuclear power plant accident using atmospheric transport modelling

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EUNADICS-AV early warning system dedicated to supporting aviation in the case of a crisis from natural airborne hazards and radionuclide clouds

The purpose of the EUNADICS-AV (European Natural Airborne Disaster Information and Coordination System for Aviation) prototype early warning system (EWS) is to develop the combined use of harmonised data products from satellite, ground-based and in situ instruments to produce alerts of airborne hazards (volcanic, dust, smoke and radionuclide clouds), satisfying the requirement of aviation air traffic management (ATM) stakeholders (https://cordis.europa.eu/project/id/723986, last access: 5 November 2021). The alert products developed by the EUNADICS-AV EWS, i.e. near-real-time (NRT) observations, email notifications and netCDF (Network Common Data Form) alert data products (called NCAP files), have shown significant interest in using selective detection of natural airborne hazards from polar-orbiting satellites. The combination of several sensors inside a single global system demonstrates the advantage of using a triggered approach to obtain selective detection from observations, which cannot initially discriminate the different aerosol types. Satellite products from hyperspectral ultraviolet–visible (UV–vis) and infrared (IR) sensors (e.g. TROPOMI – TROPOspheric Monitoring Instrument – and IASI – Infrared Atmospheric Sounding Interferometer) and a broadband geostationary imager (Spinning Enhanced Visible and InfraRed Imager; SEVIRI) and retrievals from ground-based networks (e.g. EARLINET – European Aerosol Research Lidar Network, E-PROFILE and the regional network from volcano observatories) are combined by our system to create tailored alert products (e.g. selective ash detection, SO2 column and plume height, dust cloud, and smoke from wildfires). A total of 23 different alert products are implemented, using 1 geostationary and 13 polar-orbiting satellite platforms, 3 external existing service, and 2 EU and 2 regional ground-based networks. This allows for the identification and the tracking of extreme events. The EUNADICS-AV EWS has also shown the need to implement a future relay of radiological data (gamma dose rate and radionuclides concentrations in ground-level air) in the case of a nuclear accident. This highlights the interest of operating early warnings with the use of a homogenised dataset. For the four types of airborne hazard, the EUNADICS-AV EWS has demonstrated its capability to provide NRT alert data products to trigger data assimilation and dispersion modelling providing forecasts and inverse modelling for source term estimate. Not all of our alert data products (NCAP files) are publicly disseminated. Access to our alert products is currently restricted to key users (i.e. Volcanic Ash Advisory Centres, national meteorological services, the World Meteorological Organization, governments, volcano observatories and research collaborators), as these are considered pre-decisional products. On the other hand, thanks to the EUNADICS-AV–SACS (Support to Aviation Control Service) web interface (https://sacs.aeronomie.be, last access: 5 November 2021), the main part of the satellite observations used by the EUNADICS-AV EWS is shown in NRT, with public email notification of volcanic emission and delivery of tailored images and NCAP files. All of the ATM stakeholders (e.g. pilots, airlines and passengers) can access these alert products through this free channel.Peer ReviewedArticle escrit per 46 autors/es: Hugues Brenot Nicolas Theys Lieven Clarisse Jeroen van Gent Daniel Hurtmans Sophie Vandenbussche Nikolaos Papagiannopoulos Lucia Mona Timo Virtanen Andreas Uppstu Mikhail Sofiev Luca Bugliaro Margarita Vázquez-Navarro Pascal Hedelt Michelle Maree Parks Sara Barsotti Mauro Coltelli William Moreland Simona Scollo Giuseppe Salerno Delia Arnold-Arias Marcus Hirtl Tuomas Peltonen Juhani Lahtinen Klaus Sievers Florian Lipok Rolf Rüfenacht Alexander Haefele Maxime Hervo Saskia Wagenaar Wim Som de Cerff Jos de Laat Arnoud Apituley Piet Stammes Quentin Laffineur Andy Delcloo Robertson Lennart Carl-Herbert Rokitansky Arturo Vargas Markus Kerschbaum Christian Resch Raimund Zopp Matthieu Plu 1 Vincent-Henri Peuch Michel van Roozendael Gerhard WotawaPostprint (author's final draft

Prototype of multi-hazard early warning from EUNADICS-AV systems to trigger model forecasts of European airspace

info:eu-repo/semantics/nonPublishe

How to predict seasonal weather and monsoons with radionuclide monitoring

Abstract Monsoon in India is of particular importance for the $2 trillion economy, highly dependent on agriculture. Monsoon rains water two-thirds of India’s harvest. However, the monsoon season also causes large-scale flooding, resulting in loss of human life and economic damage estimated around$7 billion annually. Beryllium-7 is a tracer that can be used to monitor the intensity of stratosphere-troposphere exchange, which varies in accordance with the annual cycle of the global atmospheric circulation (Hadley, Ferrel and Polar cells). Based on the beryllium-7 data collected globally as part of the monitoring of the Comprehensive Nuclear-Test-Ban Treaty, the presented empirical method demonstrates the possibility to predict the start, withdrawal and intensity of the Indian monsoon season. Onset can be forecasted with an unprecedented accuracy of ±3 days, 2 months in advance compared to 1–3 weeks in advance by traditional methods. Applying this new method will enable better preparation for economic and natural hazard impacts of the monsoon season in India. This method can also be extended to other regions where the movement of Hadley cells governs monsoon onset and withdrawal