Change of Wind

Abstract

The wind was analyzed on the basis of speed and direction data from three observation times at 41 meteorological stations in Poland from 1966–2018. The average annual and seasonal wind speeds and the incidence of atmospheric calms were calculated. Wind frequencies from different directions were determined using a 16-sector wind rose. Particular attention was paid to winds exceeding 8 ms−1. The seasonal and annual trends of strong winds were counted. The average wind speed was 3.6 ms−1 and ranged from 1.4 ms−1 in Zakopane to 12 ms−1 on Śnieżka. On the daily scale, the highest wind speed appeared at noon. In the annual cycle, the average wind speed at noon was the highest in spring and in the other times in winter, the lowest was always in summer. Windless weather occurred most often in the morning (12.3% of observations), less often in the evening (8.3%) and the least often at noon (3.0%). The long-term average of the highest annual wind speed oscillated between 8.3 ms−1 in Tarnów and 42.5 ms−1 on Śnieżka. Strong winds were most often recorded from the west, west southwest and west northwest directions. In southern Poland it was also the southern direction. The decreasing trends in annual and seasonal series of wind speed were observed in Poland as well as in other European countries. A number of authors attribute this trend to an increase in surface roughness.