GEOINFORMATICS RESEARCH PAPERS, publ. BS3009, doi:10.2205/2015IUGG-RU-IAPSO, 2015


National Report for the IAPSO of the IUGG 2011–2014

Edited by E. G. Morozov

Abstract

This report presents the activity of the Russian oceanographers for the period of 2011–2015.

The main scientific results obtained by the Russian oceanographers are briefly presented. The transports in the entire water column of the open ocean from the eastern coast of Greenland to Northern Europe were estimated. The flows of Antarctic Bottom Water through the Kane Gap (9oN) in the Atlantic was investigated as well as the flow of AABW into the Romanche Fracture Zone. Antarctic Bottom Water flows into the Romanche FZ through a narrow gap in the western part of the fracture. The mean horizontal velocities of the flow near the bottom are 0.40 m/s. An abyssal cyclonic eddy with a horizontal size of 100 km that does not penetrate above 1500 m was found in the Yagan Basin in the region of the Drake Passage. We found that the geographical location of abyssal eddies coincided with the similar vortexes of the Antarctic Circumpolar Current in the upper ocean. Meandering of the ACC jet in the thermocline leads to the compression of tension of the vertical water columns in the abyssal depths; therefore owing to the law of potential vorticity conservation it forms the eddies of the same sign as in the thermocline.

Mean global sea-level pressure fields corresponding to the 23 El-Nino and 25 La- Nina events observed in 1920-2012 were considered. The regions of the Earth were revealed, in which systematic differences exist between the El-Nino and La-Nina events. These are the polar regions of Canada and Pacific, Indonesia, and the near equatorial Atlantic and African regions.

Dynamics of intrathermocline lenses in the ocean was analyzed The analysis of historical observations has showed that approximately 100 lenses can exist simultaneously in this part of the ocean.

Researches were conducted in the northern seas of Russia and other marginal seas around the country. A numerical model was developed to calculate the ice cover in the Barents Sea throughout the year. The maximum ice cover was found in 2003 and the minimum in 2002. Seasonal and interannual variability of air temperature, atmospheric precipitation, wind speed, sea level, sea surface temperature, ice cover, salinity, and river runoff duirng the period from 1979 to 2011 and water areas of all the Russian seas were studied.

Long-term field and satellite observations in the shelf regions adjacent to small Russian rivers of the Caucasian coast were analyzed. Clearly manifested river plumes in the surface layer 1-4 m thick were found. The mesoscale circulation in the Black sea experienced strong changes after 2002-2003. It was revealed that the variability of the mesoscale eddy energy is in the opposite phase to the mean kinetic energy of the Black Sea circulation because the weakening of the Black Sea Rim Current leads to its instability and the formation of the mesoscale anticyclones, while the strengthening of the Rim current suppresses the instability and mesoscale eddy formation.

Measurements and modeling were carried out to study the flow in the Slupsk Furrow, a channel-like topographic constriction in the southern Baltic Sea between the Bornholm Basin and the Eastern Gotland/Gdansk basins, which is the only pathway for salty water from the North Sea to enter the deep basins of the Baltic Sea and ventilate them laterally.

Several statistically significant and physically meaningful variability patterns of sea level and eddy kinetic energy in the Japan Sea are detected by means of multivariate analysis of satellite altimetry data. Winter anomalies of the oceanographic characteristics in the Okhotsk and Japan Seas were detected on the interannual, decadal and interdecadal time scales and their linkages with surface heat flux in the North Pacific Ocean were revealed. Using high resolution satellite imagery and simulations with the eddy resolving oceanic model, dynamic structures on the shelf, over continental slope and in deep basin of the Northwestern Japan Sea were studied. Intra-seasonal and seasonal variability, including formation, movement, interaction, and decay of mesoscale and sub-mesoscale anticyclonic and cyclonic eddies, were revealed.

Relationship between sea surface temperature and surface wind speed and direction were revealed in the Okhotsk Sea, and after the propagation of typhoons.

A model of surface wave steepness was developed to estimate the steepness and of waves and their period from satellite altimetry measurements.

High-quality data were used to examine the physics of tsunami generation and propagation, in particular the tsunami energy decay. Numerical simulations of intense irregular waves were performed for conditions of laboratory experiments and for given sea states to obtain the true statistics of rogue waves taking into account strongly nonlinear effects. An asymptotic modal approach is developed for waves trapped by an opposing jet current in linear and nonlinear settings.

Published 18 June 2015.



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Citation: Morozov E. G. Ed. (2015), National Report for the IACS of the IUGG 2011–2014, Geoinf. Res. Papers, 3, BS3009, GCRAS Publ., Moscow, 59 pp. doi:10.2205/2015IUGG-RU-IAPSO