FACTOR-ANALYSIS OF SOME CLIMATOLOGICAL ELEMENTS IN ATHENS, 1931-1992 - COVARIABILITY AND CLIMATIC-CHANGE

The climatological parameters of a station are, in general, intercorre lated to various degrees (e.g. cloudiness with sunshine duration or po ssibly rainfall with temperature). In this work, 15 climatological par ameters of the National Observatory of Athens are distributed in group s where the contained parameters are highly covariant. This classifica tion is achieved using P-mode Factor Analysis, based on the monthly va lues for the period 1931-1992. Using several known criteria, we found up to four significant factors. The first two are the most important o nes including the ''temperature'' and the ''precipitation'' parameters , respectively, with loading values above 0.85. The other two are weak er and variable, depending on the month. Finally, climatic trends of t he grouped parameters (factors) are examined and the result compared w ith those of studies using classical methods.