ИСТИНА

A three-parameter mixed gamma distribution is applied for characterizing the statistical properties of the fractional cloud cover in the North Atlantic using visual cloud cover reports from voluntary observing ships (VOS) for the period from 1950 to 2017. Seasonal climatologies of the distribution parameters and the cloud cover are analyzed. The PDF-based analysis allows for the identification of the areas with different probability distributions even under the same mean total cloud cover. Analysis of interannual variability shows that in different regions of the North Atlantic, there are noticeable changes in the form of the distribution over time. In some regions, these changes are coincident with significant trends in the total cloud cover and result in changes in the distribution shape.