The distribution of global and net radiation over Greece

Abstract In the present study an attempt is made to establish the distribution of global and net radiation over Greece, with the help of meteorological data. An empirical formula based on that proposed by Budyko[1] is derived which reproduces satisfactorily the available actual measurements at the National Observatory of Athens. Parameters utilized in the equations were: elevation, absolute humidity, cloud cover, air temperature at the screen height, surface albedo. The results indicate that the main factors which contribute to the distribution of global radiation over Greece are elevation and cloudiness. The extreme values are 4.2 Kly/month over Macedonia during the winter and 18.0 Kly/month over the mountainous regions of Crete during the summer. On the other hand the main factors which contribute to the distribution of net radiation over Greece are the absolute humidity and the air temperature. The extreme values are −0.35 Kly/month over eastern Macedonia during the winter and 7.8 Kly/month over Crete and the western Peloponnesos during the summer.