Scenarios for the development of large-scale vertical circulation anomalies during warm and cold phases of El Niño-Southern Oscillation are generalized based on the NCEP/NCAR reanalysis data for . Composite models of the cells of vertical circulation in the monsoon and trade-wind regions of the tropical Pacific are obtained for the first time for El Niño and La Niña separately. An unprecedented shift of the ascending branch of the zonal Walker circulation from the "maritime continent" of Indonesia to the east, to the central and eastern Pacific, was observed during the warm phase over the tropical Pacific; this shift was accompanied by an abrupt increase in the tropical cyclogenesis activity in the southern Pacific zone of convergence. On the contrary, during the cold phase, the ascending motions in the region of the summer Australian monsoon are subject to abrupt intensification. The reconstruction of the vertical meridional circulation during the warm phase manifested itself in the almost complete disappearance of the Hadley classic circulation over the central Pacific, characteristic of the trade-wind intertropical convergence zone (ITCZ), and in its replacement by the latitudinal monsoon circulation typical of the ITCZ over the Indian Ocean. During a cold phase, the Hadley circulation is both restored and intensified.

Considered are the synoptic mechanisms of the catastrophic flood formation on the Amur River in summer 2013; these enabled revealing the set of reasons responsible for the unprecedented rise of the water level. Demonstrated is the primary importance of the series of polar-front cyclones of the unprecedented duration and intensity being the main circulation link of the summer Far Eastern monsoon. It is revealed that the intensification of monsoon rains is associated with the active participation of the marine tropical air from the Pacific Ocean in frontal processes. The simultaneous deepening of the monsoon low over the land and the strengthening of the subtropical high over the ocean became a reason for the dramatic intensification of the moisture-laden monsoon flow.

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The task of vortex boundaries setting is one of the most complexes in examination of factors influencing on the vortex (circulation system) development and destruction. In this study a new approach of vortex analysis as a whole system is proposed. It is based on vorticity equation where vorticity (left part of the equation) is defined as time coefficients of EOF-decomposition, which is integrated indexes characterizing individual vortex dynamics. Right part of the vorticity equation depicts internal and external factors influencing on the vortex. It's approbation is done on the example of an arctic-subarctic circulation system including blocking anticyclone in winter 2012 which persisted for a long time over the Atlantic sector of the Arctic and led to the formation of the largest positive air temperature anomalies and the minimum ice cover area in the Barents and Kara seas in the entire history of regular observations. It is shown that the main factor in long-term maintenance of the blocking anticyclone over the Arctic was vorticity advection, which was stabilized by horizontal heat advection.

Abstract. For the classification of the synoptic processes in the tropical Pacific using daily data, criteria were proposed for identifying the different evolutional phases of the equatorial westerly wind zone. The criteria are based on the location, extent and activity of the westerly wind zone on the 850 hPa isobaric surface. According to this classification all the observed variants of the westerly wind regime above the tropical Pacific can be divided into three classes: normal, active, and break. For each class one specific pattern of tropical atmospheric circulation centers and divergent wind velocity potential in the lower and upper troposphere are found. Using the singular value decomposition method (SVD) the connection between the atmospheric circulation and sea surface temperature (SST) of equatorial Pacific is investigated.

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The genetic and synoptic classifications of the Novorossiysk Bora are created using the data of daily observations at the Novorossiysk meteorological station and other available synoptic information. Obtained are the quantitative criteria of these classifications, and on this base worked out are the basic scenarios of the generation and evolution of this dangerous phenomenon on the Black Sea coast of Russia. According to the genetic classification, the Bora was divided into four types: frontal, air-mass, monsoon, and gravity. Quantitative criteria worked out for each type can be used for the more accurate forecast of this destructive phenomenon near Novorossiysk. According to the synoptic classification, four classes were distinguished: Azores, North Atlantic, Siberian, and Arctic.

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