Validation Of Real Time Dispersion Of Tritium Over The Western Mediterranean Basin In Different Assesments

VALIDATION OF REAL TIME DISPERSION OF TRITIUM OVER THE WESTERN MEDITERRANEAN BASIN IN DIFFERENT ASSESMENTS

P.Castro1, M.Velarde2, J. Ardao3, M.Perlado2, L.A.Sedano1
1

EURATOM-CIEMAT Association, LNF: Fusion Technology Division, Breeding Blanket Technologies Unit, 28040-Madrid, Spain, paloma.castro@ciemat.es; luis.sedano@ciemat.es 2 UPM_ETSII Nuclear Fusion Institute: DENIM, Madrid, Spain,marta@denim.upm.es; josemanuel.perlado@upm.es 3 MIMAM: Agencia Estatal de Meteorología, 28040 Madrid, Spain. jardaob@aemet.es

Real time Tritium concentrations in air coming from an ITER-like reactor as source were coupled the European Centre Medium Range Weather Forecast (ECMWF) numerical model with the lagrangian atmospheric dispersion model FLEXPART. This tool ECMWF/FLEXPART was analyzed innormal operating conditions in the Western Mediterranean Basin during 45 days at summer 2010. From comparison with NORMTRI plumes over Western Mediterranean Basin [1] the real time results have demonstrated an overestimation of the corresponding climatologically sequence Tritium concentrations in air outputs, at several distances from the reactor. For these purpose two clouds development patternswere established. The first one was following a cyclonic circulation over the Mediterranean Sea and the second one was based in the cloud delivered over the Interior of the Iberian Peninsula by another stabilized circulation corresponding to a High. One of the important remaining activities defined then, was the tool qualification. The aim of this paper is to present the ECMWF/FLEXPART productsconfronted with Tritium concentration in air data. For this purpose a database to develop and validate ECMWF/FLEXPART tritium in both assessments has been selected from a NORMTRI run. Similarities and differences, underestimation and overestimation with NORMTRI will allow for refinement in some features of ECMWF/FLEXPART.

Vandellós. For ECMWF/FLEXPART we have formed a new data base of bothchemical forms of atmospheric tritium HT and HTO, from the 1st of October 2010 until the 31st of March 2011. I.A. Point of emission, levels in air and source term We assume major concentration activity of the tritiated species should be in the very low levels. Therefore we have selected 10, 30 and 60 meters for obtaining ECMWF/FLEXPART products of the emission release of tritium (when in continuousdisplacement in the boundary layer), (Ref. 3). The source term is placed in Vandellós, this is considered the point of release in routine. Fictitious exaggerated tritium sources of about 2.7 mg of tritium per event-day (~ 25 Ci/event-d) in HT form (e.g. emitted 3.65 mg of HT) or 0.27 mg (~ 2.5 Ci/event-d) of tritium per event-day in HTO (e.g. emitted: 1.8 mg of HTO) (Ref. 3). The dispersion ofatmospheric tritium can be very different, as a function of the water vapor tritiated clouds development and movement (stratified or convective, horizontal or with vertical ascendant or descendent air currents). In order to compare the tritium concentrations in air taken by both models, we will compare the same source term in both models. This has been verified both for NORMTRI and ECMWF/FLEXPART outputsdifferent for HT. For example the 3 “weather sequences” in NORMTRI ranges for a total of 66,9 TBq (for HT) and the source term in ECMWF/FLEXPART is around 0,0027 g/day. Therefore both are really the same in both NORMTRI and ECMWF/FLEXPART numerical models. I.A.1. ECMWF/FLEXPART On one hand FLEXPART is a Lagrangian Model of atmospheric contaminants, here adapted in both chemical forms ofatmospheric tritium, using as input data the outputs of the numerical weather prediction model of the European Center for Medium Range Weather Forecast. As the numerical ECMWF model has 91 levels in the

I. INTRODUCTION: NORMTRI AND ECMWF/FLEXPART MODEL The objective of this paper is to make a useful and simple validation of the Lagrangian Atmospheric coupled ECMWF/FLEXPART model applied to atmospheric...