Climatología de vientos ligeros sobre Europa a partir del reanálisis ERA5 (1979-2018)

Abstract

Low-wind characterization from climatic and meteorological perspectives is a challenging research area, as there is no objective definition for these atmospheric conditions, locally and over large regions. A definition based on light-breeze Beaufort wind scale threshold (3.3 m/s) with hourly data obtained from 0.25º ERA5 reanalysis for the 1979-2018 period is used to analyze their main climatic features over the whole European region, for both land and oceanic regions, once a validation with the limited amount of observational data is first made. Around 3500 low-wind hours/year are obtained, averaged over the 40-year period. Spatial patterns related to orography, oceanic areas and north-to-south gradients can be seen. Seasonal low-wind variability ranges around 20-25%, with important interannual variability. Consecutive low-wind hourly spells episodes last 5-10 days over land areas, with a mean spell length of around 20 hours, and more than 200 episodes per year.