Spatial coverage of cyclonic wind exposure coefficients

This dataset provides a series of gridded geographical grids (raster) by territory. These grids define at all points, with the exception of a few so-called "uncovered" areas, exposure coefficients to cyclonic winds at four reference heights: 6m, 10m, 15m and 20m. The geographical areas covered by the study are Martinique and Guadeloupe. These exposure coefficients are necessary for **calculating the peak dynamic pressure qp** resulting from Eurocode 1-4 (NF EN 1991-1-4 and its National Annex NF EN 1991-1-4/NA) and necessary for calculating the action of wind on buildings. These data have been produced in support of the paracyclonic regulations which provide construction stakeholders (design offices, architects, builders, craftsmen and other professionals) with the exposure coefficients for each of the territories concerned. The data comes from simulations of type CFD (Computational Fluid Dynamics) with meshes of 250m or 180m depending on the territory and the available data. The map displaying the exposure coefficients shall be accompanied by a [instructions for use] (https://files.georisques.fr/paracyclonic/CSTB_Cartographie_coefficient_exposition-Notice_d_utilisation.pdf) specifying the modalities of use of the data for the constructions located in the mapped areas and by a [instructions for use] (https://files.georisques.fr/paracyclonic/CSTB_Cartographie_coefficient_exposition-Notice_explicative.pdf) specifying the alternative calculation methods for the uncovered areas where the exposure coefficients are not available. These zones were defined to say expertly, indeed the simulation had limits of geometric definition which did not allow to consider certain unfavourable situations (sharp relief) with regard to the mesh of the model. This data can be viewed simply online** via the dedicated [interactive map] (https://www.georisques.gouv.fr/cartes-interactives#/), by querying a point in the territory.