ATMOSPHERIC INTRASEASONAL OSCILLATIONS IN THE MIDDLE LATITUDES OF EUROPE AND ASIA AND THEIR PARAMETERS

V. N. Ivanov, A. M. Sterin, and A. V. Khokhlova

Long-term aerological and meteorological observations are used to estimate parameters of atmospheric intraseasonal oscillations over Europe and Asia in the range of 30—50 day periods. The oscillations were discovered for the first time in the tropical Indian and Pacific oceans by Madden and Julian (the Madden—Julian oscillation, or MJO). Spectral densities of the time variability of basic meteorological elements are given. They confirm the existence of these oscillations in the middle latitudes over Europe and Asia and point to the inhomogeneity of the geographical distribution of their activity. The interannual variability of the activity of intraseasonal oscillations is calculated, and the influence of lower frequency components is estimated. The results of calculations of phase relations for the MJO range are presented which point to the connection of the MJO with the tropical zone and provide an opportunity to estimate characteristic values of the zonal wavenumbers corresponding to 5000—10,000 km wavelengths.