Предложен новый метод расчета распространения опресненных вод от Обско-Енисейского взморья по акватории Карского моря на основе совместного учета влияния ветрового дрейфа и геострофических течений. Этот метод базируется на расчете течений в верхнем перемешанном слое с использованием средней динамической топографии морской поверхности, регулярных данных спутниковой альтиметрии об аномалиях уровня моря и параметризации ветрового дрейфа. Он уже использовался ранее для описания поверхностных течений в Черном море [7, 12]. Данный метод успешно верифицируется на основе сопоставления с данными натурных наблюдений в Карском море и спутниковыми изображениями морской поверхности в поле хлорофилла.

The report presents the results of the studies of the reduced sulfur species in the water of the anoxic zone of the Black Sea. The content of hydrogen sulfide was determined by means of spectrophotometry using dilution with oxygen-free distilled water. The detection limit of the H 2 S amounted to 0.3 μM with the method’s precision below 3%. The accuracy of the spectrophotometric determination was verified by iodometry after the fixation of the hydrogen sulfide in zinc acetate under the distillation with argon from the acidified seawater sample.

Results of the studies of the spatiotemporal variability in the hydrophysical and hydrodynamical structure of the shelf area and its dependence on the water dynamics of the deep-water zone of the Black Sea off Gelendzhik are presented and discussed. The field materials were collected in early October of 2006 with the use of traditional and new measurement techniques. A combined analysis of on-line satellite oceanological information, data of onboard surveys, and data time series of the vertical profiling of the hydrophysical characteristics at a moored buoy station was performed.

An analysis of the data of measurements of the fine structure and microstructure fluctuations of hydrophysical fields in the upper 200-m layer of the Black Sea carried out using CTD profilers and a Baklan free falling microstructure and turbulence profiler revealed the existence of a positive correlation between the intensity of the fine structure and microstructure fluctuations and the dynamics of the currents. On the other hand, the level of the fine structure and microstructure fluctuations reflects the rate of the vertical turbulent exchange. It was shown that, in the case of the absence of the Black Sea Rim Current (BSRC) jet or clearly manifested mesoscale eddy structures, the vertical turbulent exchange in the pycnocline is weak, while, in the opposite case, it is stronger. The results obtained support the supposition that the interbasin dynamics play an important role in the maintenance of the rate of small-scale mixing in the pycnocline and halocline and provide the vertical transport of dissolved oxygen from the cold intermediate layer into the deeper layers of the sea.

The dynamics and structure of near-bottom gravity currents over a sloping bottom in a homogeneous nonrotating fluid and the interaction of the currents with the pycnocline in a two-layered fluid are studied under laboratory conditions. Different regimes of the denser water downwelling are revealed, among them is a wave regime that was poorly known before. Under certain conditions, the gravity current branches in the vertical plane near the pycnocline. The top branch of the current flows into the pycnocline as an intrusion, whereas the bottom branch penetrates under the pycnocline and continues to sink over the sloping bottom. A mathematical model of the gravity current was also developed to describe the laboratory experiments. The numerical experiments were performed to reveal the different regimes of the gravity currents. The results of the numerical experiments agree qualitatively and quantitatively with the results of the laboratory experiments, which suggests the validity of the model and the possibility of its use for modeling gravity currents over the continental slope.

Работа выполнялась в рамках Госконтракта № 11.519.11.5020 «Черноморский экспериментальный подспутниковый полигон в целях мониторинга состояния и исследования прибрежной экосистемы» с Минобрнауки России (2011-2013 гг.), Программы 23 РАН «Фундаментальные проблемы океанологии: физика, геология, биология, экология», Программы сотрудничества РАН – НАН Украины «Черное море как имитационная модель океана» и грантов РФФИ №11-05-00830, 13-05-92608, 13-05-00777.