Regional winds over the Iberian Peninsula with COSMO-REA6 high resolution regional reanalysis: cierzo, levante and poniente

Regional winds are caused by small-scale pressure differences in a way that important air flows can arise in a very small and specific region. Sometimes an orographic feature, such as a channel like the Ebro Valley or the Strait of Gibraltar, lead the wind, due to mass conservation, to acquire a certain specific range of directions and considerable speed. In the regions where they are observed, the wind is of great importance not only for the climatology and meteorology of these areas but also for their culture and identity. However, it is difficult to analyze them using the most common reanalysis products, since their spatial resolutions are not high enough to properly describe the orographic characteristics that lead to the regional winds in specific locations. Here, we will explore the application of the COSMO-REA6 high resolution reanalysis system for the assessment of the main regional winds in the Iberian Peninsula: the cierzo wind in the Ebro Valley and the levante and poniente winds in the Strait of Gibraltar, for the 2000-2018 period. COSMO-REA6 uses a spatial resolution of 6 km (0.055º), which is much larger than previous reanalysis and regional modelling databases, so it can better capture the orography of the areas and therefore the regional winds we intend to study. The cierzo, levante and poniente winds are very relevant in the Iberian Peninsula due to their intensity and their frequency. Defined with a 5 m/s threshold for each hour, and their specific direction range, around 95, 150 and 110 wind days per year are obtained, respectively. Their study may also be important for other reasons, such as the production of renewable energy in these areas. First, we conduct a preliminary assessment of wind speed and direction with hourly data from weather stations, which have been obtained from the HadISD global sub-daily dataset. Then, we compare data from stations with COSMO-REA6 reanalysis in each location and produce a spatial description of the reanalysis in the Peninsula. We also study the atmospheric patterns associated with the regional winds characterized above. Due to the few studies that have been carried out on regional winds in the Iberian Peninsula, these results can be of great interest for various fields, such as meteorology, climatology and the generation of renewable energy.