Об особенностях структуры мультидекадной осцилляции Мирового океана

Abstract

One of the most remarkable peculiarities of the modern climate, undoubtedly, should be recognized as the climatic shift observed in the mid-70s of the last century. The reasons for this phenomenon for a long time, despite the activation of climatologists from all over the world, remained a mystery that requires its disclosure. First of all, this was due to the fact that the shift that took place turned out to be unexpected for scientists and was accompanied by rapid qualitative changes in the planetary climate. To date, thanks to the efforts of scientists using the results of rapidly developing numerical modeling, diagnostic calculations and observational data in large hydrophysical experiments in various regions of the World Ocean (WO), an understanding of the role of the ocean factor in the variability of the current climate has developed. It became clear that climatic shifts are an important feature of the internal dynamics of the climate system. The most obvious evidence of intrasystemic processes should be considered the discovered planetary structures in the atmosphere – Global Atmospheric Oscillation (GAO) and in the ocean – Multi-decadal Oscillation of the Heat content in the Ocean (MOHO), which are quasi-synchronous accompanying variations in the modern climate. GAO, its structure and features have been discussed in detail earlier in a number of studies. As for the MOHO, its structure and features are discussed in the proposed work. It is characteristic that the MOHO is located in the layer of the main thermocline (100-600 m). In a quasi-uniform layer (0–100 m), and in a deep layer (600-5500 m), the thermodynamic regime differs from the regime in the layer of the main thermocline. Probably, it is precisely this circumstance that did not allow earlier to draw attention to such an important detail in the structure of the WO thermodynamic variability. The presence of extreme multi-decadal temperature field disturbances at intermediate levels (200, 300, 400, 500, 600 m) should be noted as an important characteristic feature of the oscillation. Large-scale hydrophysical experiments (POLYGON-70, POLYMODE, etc.) made it possible to reveal the vortex structure in the dynamics of WO waters and to discover that the vortices of the open ocean have maxima of kinetic energy precisely in the layer of the main thermocline. This allows us to assume a connection between synoptic eddy activity and MOHO. However, the latter remains to be studied.