Abstract: In this paper,500 hPa monthly mean geopotential height field has been analysed to determine the dominant modes of united spatial,seasonal and interannual varioability.A time-space synthetic empirical orthogonal function (EOF) analysis is used to reveal the modes which explain most of the variance for the period 1951-1984.The EOFs reveal the abrupt seasonal change and rhythm of atmospheric general circulation in Nothern Hemisphere.Time series associated with the EOFs reveal quasi-period fluctuations and the climatic jumps.