Atmospheric cloudiness and sunshine duration are the most important climatic parameters in assessing the radiative potential of a certain region which influences ecosystems, particularly, plants grow and developement. Cloudiness represents the totality of the clouds of the sky, or, in an exact sense, the degree of sky coverage with clouds, expressed in tenths of overcast covered sky. The degree of sky coverage and the clouds types are dependent on the evolution of air masses, on the afferent atmospheric fronts and underlying surface features. The sunshine duration represents the time interval corresponding to the presence of the solar disk on the sky and it is expressed in hours and tenths of hour. The two parameters are in an inverse relationship, the high cloudiness causes a low sunshine. In this paper, there was analysed annual, seasonal, monthly cloudiness and sunshine duration variation, in the Câmpulung Depression, in the 1961-2010 period, 1971-2010-period respectively. In this region, the cloudiness regime records a maximum in April and a minimum in August, while the sunshine duration has a minimum in December and a maximum in July.
Cloudiness frequency, Lower cloudiness, Total cloudiness, Percentage of possible sunshine, Sunshine duration.
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