Global Distribution of Total Cloud Cover and Cloud Type Amounts Over the Ocean

This is the fourth of a series of atlases to result from a study of the global cloud distribution from ground-based observations. The first two atlases (NCAR/TN-201+STR and NCAR/TN-241+STR) described the frequency of occurrence of each cloud type and the co-occurrence of different types, but included no information about cloud amounts. The third atlas (NCAR/TN- 273+STR) described, for the land areas of the earth, the average total cloud cover and the amounts of each cloud type, and their geographical, diurnal, seasonal, and interannual variations, as well as the average base heights of the low clouds. This fourth atlas describes for the ocean areas of the earth, the average total cloud cover and the amounts of each cloud type, and their geographical, diurnal, seasonal, and interannual variations, as well as the average base heights of the low clouds. This atlas complements our cloud climatology for the land (NCAR/TN-273+STR). Since the methods of analysis are in large part the same for both ocean and land cloud observations, extensive discussion of those methods is not repeated here. The text of the land atlas should be considered as background information for this atlas. The text of this atlas discusses problems which are specific to the ocean data.