A multi-year study of sea breezes in a Mediterranean coastal site: Alicante (Spain)

Using 6-year data collected in a high-resolution network of 19 stations in the province of Alicante (Spain), the characteristics of sea breezes for the period 2000-2005 were studied. This study attempts to develop a multi-year climatology of sea breeze flows focusing on a Western Mediterranean coastal site. We used half-hourly meteorological records from a reference station in Alicante and sea surface temperature measurements at Albufereta beach to identify past sea breeze episodes, on the basis of an objective selection technique. A total of 475 sea breeze events during the 6-year period were identified and the following parameters were determined: mean time of onset, mean wind speed and direction at the time of onset, mean time of cessation, mean temporal dimension (duration), mean maximum velocity, mean time of maximum velocity and mean wind path of the sea breeze. The mean onset and cessation times are 0940 UTC and 2009 UTC (local standard time= UTC +0100 h, or +0200 h with daylight-saving time), respectively, with a mean duration of 1029 h. The mean wind speed at the time of the passage of sea breeze fronts is low (2.07 m s-1), but sea breeze gust intensities range from 3.6 to 11.6 m s-1 and they generally occur during 1200-1300 UTC. Southerly and southeasterly onset flows dominate in winter, whereas more easterly onsets occur in spring and summer. The mean inland directed wind path of the sea breezes is 97.7 km with noteworthy differences throughout the year; a case study showed onshore wind peaks of 11.1 m s-1, 50-km inland of the Vinalop´o river valley in the late afternoon. The spatial and temporal change in wind speed and direction were also analysed, using multi-year wind hodographs for the 19 stations and eight well-defined synoptic patterns favouring the development of sea breezes.