Abstract: In this paper,a concentrative function used in statistics is designed to present the extent in which an elementary field concentrates in the spatial distribution.Its characteristics are discussed and its availability proved.From its application in the atmospheric and oceanic sciences,we can find some interesting phenomena.For example,there is a clear seasonal concentricity in the occurrence of storms in every oceanic area in a year.The stormsdense months correspond to such an geographical place that goes around anticlockwise in the tropical oceanic areas.The spatial concentricity of SST and that of cloud change with time in a year in a similar way,that is,the higher occurrence of storms,the higher concentricity of SST and cloud,maybe the higher possibility of floods,which shows possibly that SST and its distribution play important role in the formation of cloud and that the formation of storms contributes to the concentration of the cloud.