Volume XI |

The wind regime of Romania – Characteristics, trends and North Atlantic oscillation influences

Abstract: The present study attempts to develop a comprehensive perspective of the wind regime on the Romanian territory, focusing on the characteristics and tendencies encountered over the past 50 years, as well as on the NAO projection on it, using several data categories gathered from 167 meteorological stations. Based on the recorded multiannual averages and on the strong correlation (r = 0.87) established between altitude and wind speed in wind exposed areas, we created the map of mean (multi)annual wind speed. The highest aeolian potential corresponds to the Carpathians (7-10 m/s on the ridges and 3-7 m/s on the slopes and within valleys) and the Black Sea Shore (5-7 m/s); nevertheless, the two areas develop extreme values of the wind turbulence – maximum in the Carpathians and minimum in the coastal units. Tablelands in Moldova and Dobrogea, as well as the northern part of Bărăgan show ideal conditions for the development of aeolian parks (moderate and strong winds, low turbulences). On a country-size scale, the month with the highest mean wid speed is March, whereas August is the calmest one. For the first time, the map of resultant wind direction (DRV) was designed, expressing both the resultant wind orrientation and its intensity (high intensity = low directional variability). Concerning NAO, a negative correlation is observed between its indices and the wind speed (mean speed, frequency and intensity of the stromic events) at a multiannual and multidecadal scale. The correlation coefficients present high values in the extra-carpathian areas and small or moderate values in the intra-carpathian areas. The positive (negative) NAO associated with low (high) cyclogenesis over the Mediterranean area induce low (high) winds over the Romanian territory due to diminished (enhanced) frequency of cyclones reaching Romanian regions.