An updated wind hazard map of Italy

The available wind hazard map of Italy was drafted in the mid-1990s, based on anemometric measurements mostly carried out between 1951 and 1973, with a minor portion extending to 1992. It contains shortcomings deriving from the pre-processing and statistical analysis of the data, which the authors themselves declared at the time of publication. For this reason, the need was felt to update it using more recent data and improving the transparency of the procedures. The proposed new map is subjected to the same limitation of the existing one of considering only synoptic winds, which have dominated the European extreme wind climate until now. It has been prepared in compliance with the probabilistic format adopted by the Eurocodes, and it is therefore ready for use within national and international standards. Analysis of data available for the period from 1944 to 2020 suggests an increase of the design wind velocities, especially in the southern part of the country and in the islands. The updated map divides Italy into eight zones to which fundamental values of the basic wind velocity ranging between 25 and 36 ms-1 apply. Altitude correction is necessary for five zones, and starts from altitudes ranging between 0 and 500 m above sea level. The updated map is unbiased on average, and has a limited scatter of bias within each zone, corresponding to a CoV never exceeding 0.17, therefore it is expected to reduce the uncertainty on wind loads on buildings and other exposed constructions.