Studies concerning the empirical relationship of cloud shade to point cloudiness (Romania)

Summary This paper analyses the accuracy of three simple relationships of cloud shade (CS) to point cloudiness (PC). 1740 pairs of monthly average values (CS, PC) from twenty-nine weather stations of Romania were used. The following statistical indicators of accuracy were used: the mean bias error, the mean absolute error and the root mean square error. Also, a bootstraping technique provided a general way to evaluate the confidence and significance associated with each of the statistical indicators of accuracy. The paper deals with the accuracy of the empirical relationships when applied in other areas and time intervals than the ones where the relations were determined.With 10 Figures