World Atlas of Total Sky-Cover.

The purpose of this atlas is to establish a global cloud climatology that details seasonal and diurnal variations. The Boehm Sawtooth Wave (BSW) simulation model is used to devise a method for describing the frequency distribution of total sky-cover. Two parameters, scale distance and mean sky-cover, permit the calculation of the sky cover distribution from clear to overcast. This is an efficient means of data storage, since two numbers define the entire frequency distribution. Hence, the frequency distribution of sky cover can be found for locations world-wide using the global analyses of mean sky cover and scale distance given in the atlas. Twenty maps are presented for each of these parameters - one set 4 times daily (0000-0200, 0600--0800, 1200-1400, 1800-2000 LST), for each midseason month (January, April, July, and October), and another set of monthly means for all hours for each midseason month.