Purpose. The purpose of the work is to study the features of the response of sea level fields and currents in the system of the North and Baltic Seas to the impact of changes in atmospheric pressure and tangential wind stress during the formation of the Major Baltic Inflow in 2014, based on reanalysis data on meteorological and hydrophysical fields, as well as numerical experiments using a three-dimensional baroclinic hydrodynamic model.

Methods and Results. To achieve the stated goal, the following procedures were performed: decomposition of hydrometeorological fields into complex natural orthogonal functions; cross-correlation and cross-wavelet analysis between the main components of field decomposition; spectral, cross-correlation and cross-spectral analysis of current oscillations and tangential wind stress; free level oscillations were modeled, and their spectral structure was compared with the spectra of current oscillations during a large inflow.

Conclusions. During the formation and propagation of the Major Baltic Inflow in 2014, the main energy transfer from the baric formations to the movement of water masses took place in the range of several weeks, while in a year without an inflow, it occurred in the range of several days. During the large inflow, the water mass response to the impact of anemobaric forces occurred in the form of low-frequency wave processes, which had the signs of progressive and standing modes of wave motion. The analysis both of the synoptic situation over the North Atlantic and the results of numerical hydrodynamic modeling of free level fluctuations in the system of the North and Baltic Seas has shown that the largest sea level gradients between the Kattegat Strait and the southwestern Baltic, as well as the highest current velocities in the Danish Straits, were observed during the Major Baltic Inflow on December 11, 2014, when the movement of a deep atmospheric cyclone slowed down sharply to 1.0 m/s, and its speed became equal to the phase velocities of free low-frequency waves in the North and Baltic Seas. This fact makes it possible to further investigate the hypothesis about the resonance mechanism for the generation of Major Baltic Inflows.