Spectral barotropic model for the prediction of synoptic currents in the open part of the ocean

We consider a quasigeostrophic spectral model used for the prediction of synoptic currents in the barotropic ocean. The spectral method is based on the expansion of the current function in a double series in cosines. An algorithm of numerical evaluation of the nonlinear term in the equation of potential eddy is described in detail. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 62–69, July–August, 2006.     

Assimilation of climatic hydrological data in a Black-Sea model based on the algorithm of adaptive statistics of prognostic errors

We propose an algorithm of adaptive statistics of prognostic errors aimed at the assimilation of the climatic temperature and salinity fields in a model of dynamics of the sea. The algorithm is used for the numerical solution of the proposed differential equations for the dispersions of prognostic errors of temperature and salinity. The sources in the equations of advective diffusion of heat and salt depend on the four-dimensional dispersions of prognostic errors and one-dimensional (along the vertical coordinate) dispersions of measurement errors. The dispersions of prognostic errors are corrected at the times of assimilation of the data. We perform the reconstruction and analysis of the climatic fields of currents in the Black Sea. It is shown that the structure of the fields of dispersions in the upper mixed layer is determined by the vertical diffusion. Below this layer, the distribution of dispersions depends on the vertical advection. The algorithm of adaptive statistics of prognostic errors allows us to reconstruct the improved mutually adapted hydrophysical parameters with regard for the dynamics of the dispersions of errors. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 26–37, January–February, 2008.     

Investigation of the sensitivity of the Mellor–Yamada parametrization to the choice of finite-difference analogs in a numerical three-dimensional model of the operative prediction of currents in the black sea

Within the framework of the Mellor–Yamada approach, we realize a numerical scheme for the calculation of the coefficients of turbulent viscosity and diffusion in the z -system of coordinates for the three-dimensional model of operative prediction of currents in the Black Sea. Some discrete analogs of the equations for turbulent kinetic energy and turbulence macroscale are studied. Their high sensitivity to the choice of finite-difference approximations is demonstrated. On the basis of the comparison of the results of prognostic experiments with the data of observations, we choose the best approximation of the term used to describe the generation pf turbulence energy.     

Simulation of wind-induced oscillations of the Azov-Sea level

The prognostic fields of the surface winds and atmospheric pressure obtained according to the data of the Skiron prognostic system are used to study the surge phenomena in the Azov Sea by using a three-dimensional nonlinear model. The accumulated numerical results are compared with the data of direct measurements of the sea level at the coastal stations. The degree of sensitivity of the computed levels of surges to the value of the coefficient of surface friction is evaluated. Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 53–65, November–December, 2008.     

Reconstruction of the seasonal climate of the Black Sea on the basis of available hydrological data

We analyze the seasonal variability of the climatic hydrophysical fields of the Black Sea reporduced in three numerical experiments carried out according to the model of circulation. The numerical predictions are performed for a period of 12.5 yr on the basis of the hydrological data accumulated in 1983–1995. The monthly average climatic fields of the current speed are reconstructed according to the data on the climatic fields of temperature and salinity by the method of hydrodynamic adaptation (standard). It is shown that, in prognostic calculations, the seasonal variability of temperature and salinity is qualitatively close to the “standard” dependence. At the same time, the quantitative difference between the climatic behavior of the model and the standard dependence may be significant. The annual cycle of the currents is characterized by the intensification of the Main Black-Sea Current in winter. The structure of the hydrophysical fields of the sea in the model becomes much more realistic if it is based on the actual hydrological data. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Assimilation of the data of observations and adaptive prediction of the natural processes

We propose a dynamical model for the prediction of random components of natural processes. The model is based on the system concept of adaptive balance of causes (ABC-model) and contains dynamic equations for the coefficients of influence adapted to the correlations existing in the predicted processes. To improve the accuracy of predictions, we consider two possible schemes of assimilation of the data of observations in the equations of the ABC-model, namely, the Kolmogorov and Kalman schemes. Both schemes are oriented toward the application of sample correlation coefficients for the prediction of time series of measurements and, hence, take into account the nonstationarity of actual natural processes. We present some examples of prediction of the simulated time series clarifying the algorithms of assimilation of the data of observations. A conclusion is made that the methods of systems modeling and adaptive prediction of random processes by the ABC-method are quite promising.     

Creation of the database of monitoring of the Black Sea by using drifters

We consider some specific features of creation of the database according to the results of drifter experiments carried out in the Black Sea in 2001–2006. The general statistical information on all buoy studies in the sea is presented. The criteria used to filter the primary data are suggested. The principles of formation and structuring of the drifter database are presented. As an example, we describe the procedure and the results of comparison of model estimates with the data of contact measurements of the sea-surface temperature by drifting buoys.     

Integrated Management of Economic-Ecological Sea-Land Systems

We propose an information technology of integrated management of sea-land systems containing 17 correlated biochemical processes and an economic model of industry consuming biological, mineral, and ecological marine resources. Both models are constructed by the method of adaptive balance of causes (ABC-method) and contain intelligent management agents. The technology of integrated management includes the resource rent, environmental-protection taxes, and ecological fines. We consider an example of integrated management for simulated external actions upon the marine ecosystem and the land-based economic system. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 59–76, July–August, 2005.     

Adaptive balance of global development processes

We study the processes of global self-regulation of Earth’s biota (GAIA-theory) by applying the method of adaptive balance of causes proposed by the authors. By using, as an example, the Daisy World model constructed by this method, we reveal the phenomenon of preservation of the mean temperature of Earth’s surface due to the presence of the vegetation cover. We develop an integral model of global natural, social, and economic processes in which the World Ocean is one of the factors regulating the amount of greenhouse gases in the atmosphere. The decrease in the amount of greenhouse gases in the atmosphere caused by the GAIA-effects increases the number of hurricanes and floods on the Earth. As a result, the levels of ecological and social hazards for the mankind become much higher. To eliminate these threats, it is necessary to intensify the processes of self-organization of the society realized via the improvement of education, development of science, and global regulation of the competition for natural resources. We present the results of numerical experiments performed by using the model demonstrating possible scenarios of global development with regard for the processes of self-organization of the society. __________ Translated From Morskoi Gidrofizicheskii Zhurnal, No. 3, Pp. 62–80, May–June, 2007.     

Retrieving of the biooptical characteristics of Black-Sea waters under the conditions of constant reflectance at a wavelength of 400 nm

We consider a method used for the solution of the inverse problem of biooptics of the sea according to the spectrum of upwelling radiation and propose a procedure for the correction of the data of measurement by fixing the value of reflectance at a wavelength of 400 nm. The influence of this assumption on the results of retrieving of the concentrations of admixtures in seawater is analyzed. The computed values of the concentration of chlorophyll correspond to the data of direct biological measurements, and the reconstructed spectra of the absorption coefficient of phytoplankton have local maxima typical of biological particles. The applied correction allows us to decrease the influence of measurement errors on the results of retrieving and to increase the stability of solution of the inverse problem. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 38–50, January–February, 2008.     

基于SVM回归模型的SAR图像有效波高估测

A new method for estimating significant wave height(SWH) from advanced synthetic aperture radar(ASAR) wave mode data based on a support vector machine(SVM) regression model is presented. The model is established based on a nonlinear relationship between σ0, the variance of the normalized SAR image, SAR image spectrum spectral decomposition parameters and ocean wave SWH. The feature parameters of the SAR images are the input parameters of the SVM regression model, and the SWH provided by the European Centre for Medium-range Weather Forecasts(ECMWF) is the output parameter. On the basis of ASAR matching data set, a particle swarm optimization(PSO) algorithm is used to optimize the input kernel parameters of the SVM regression model and to establish the SVM model. The SWH estimation results yielded by this model are compared with the ECMWF reanalysis data and the buoy data. The RMSE values of the SWH are 0.34 and 0.48 m, and the correlation coefficient is 0.94 and 0.81, respectively. The results show that the SVM regression model is an effective method for estimating the SWH from the SAR data. The advantage of this model is that SAR data may serve as an independent data source for retrieving the SWH, which can avoid the complicated solution process associated with wave spectra.     

Field Study of the Space Uniformity of Meteorological and Wave Parameters in the Coastal Zone. On the Problem of Calibration of a Side-Looking Radar on the <Emphasis Type="Italic">Sich-1M</Emphasis> Satellite as an Instrument for Measuring Wind Velocity over the Sea

We study the problem of subsatellite calibration of a side-looking radar (SLR) of the Sich-1M satellite regarded as an instrument for the evaluation of the velocity of surface wind and discuss the possibility of application of the meteorological and wave parameters measured from the stationary oceanographic platform of the Experimental Department of the Marine Hydrophysical Institute (Ukrainian Academy of Sciences) for their evaluation in the remote regions of the sea. These regions can be observed with the help of the SLR without errors introduced by the appearance of the coast in elements of space resolution. To prove the indicated possibility experimentally, we perform simultaneous measurements of the water and air temperatures, wind velocity, and the characteristics of waves both from the platform and in the water area neighboring with the platform on the side of the sea at distances of up to 4.8 km. The quantitative estimates of the degree of space uniformity of the analyzed parameters are deduced under the conditions of stable inshore wind. A conclusion is made that the platform can be used for subsatellite measurements aimed at the validation and improvement of the algorithm of reconstruction of the velocity of surface wind by using the SLR of the Sich-1M satellite. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 31–43, May–June, 2005.     

Modeling of decadal variations in the Black-Sea ecosystem

We consider the decadal evolution of the Black-Sea ecosystem on the basis of a three-dimensional coupled model consisting of the Black-Sea circulation model and a biogeochemical block. The circulation model is based on the widely used POM (Princeton Ocean Model) model. The calculated hydrophysical fields are interpolated then to levels of the biogeochemical model, which covers the upper 150-m layer. We demonstrate the close relationship between the interannual variation of hydrophysical fields and the evolution of the main elements of the ecosystem. The period under consideration (1992–2001) is characterized by the warming of the Black-Sea upper layer, which can be traced by the trend of a growing surface temperature. It follows from the results of modeling that the process of warming is also revealed in the subsurface hydrophysical characteristics and the dynamics of the main elements of the Black-Sea ecosystem.     

Visualization of the results of hydrothermodynamic modeling

We describe a software package developed for the visualization of the results of hydrothermodynamic modeling and called the User Visualization Tool (UVT). The contemporary requirements to the software of this sort are discussed. The UVT software enables one to perform the efficient construction of the maps, vertical profiles, time series, and the sections of variability of the scalar and vector variables of state of the sea. By using the models of the Mediterranean and Adriatic Seas as an example, we demonstrate some possibilities of the package, perform its comparison with similar software packages, and estimate the trends of its subsequent development. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 59–68, September–October, 2007.     

Algorithm for HF radar vector current measurements

A new algorithm is proposed, called the stream function method (SFM) for producing vector current maps from radial data measured by dual-site high frequency surface wave radar (HFSWR). In SFM, a scalar stream function is constructed under some oceanographic assumptions. The function describes the two-dimensional (2-D) ocean surface water motion and is used to obtain the distribution of vector currents. The performance of SFM is evaluated using simulated radial data, which demonstrates that SFM has advantages over typical vectorial combination methods (VCM) both in error acceptance and robustness, and excels another method based on least-squares fitting (LSF) in recovering the complicated current models. Furthermore, SFM is capable of providing the total currents based on radials from single-site radar. We also test the assumptions of horizontal non-divergence in the simulation. The new algorithm is applied to the field experiment data of Wuhan University’s ocean state measuring and analyzing radar (OSMAR), collected in the coastal East China Sea during April 11–17, 2004. Quantitative comparisons are given between radar results by three current algorithms and in-situ current meter measurements. Preliminary analysis of the vertical current shear is given based on the current meter measurements.     

基于非线性薛定谔方程的波浪预报方法研究

为探索海浪波面信息的实时预报方法,以三阶非线性薛定谔(NLS)方程的逆散射变换求解为基础,通过理论推导,给出了一种由实测波高时历数据计算其NLS方程本征值的方法,进一步实现了对波浪包络时空演变的预报。通过预报结果与实测波列的比对,验证了方法的有效性和准确性。该方法可为船舶或海上平台的大浪预警,以及为大波浪中海上作业寻找窗口期等提供一条新的技术途径。     

Improved interpretation of the data of observations of the black sea by a SeaWiFS satellite instrument in autumn 1998

By analyzing, as an example, the data of observations of the Black Sea from the space in autumn 1998, we conclude that, in some cases, the atmospheric distortions manifest themselves in all measuring channels of SeaWiFS instruments and lead to significant errors in determining the concentration of chlorophyll according to the standard NASA algorithm. After additional rejection of the data with negative values of the spectral brightness of the sea surface at a wavelength of 412 nm, the results of evaluation the concentration of chlorophyll are in good agreement with the available data of direct measurements. We also present a detailed discussion of some specific features of operation of the NASA algorithm of atmospheric correction playing an important role in the interpretation of the data of observations of the Black Sea. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 68–79, March–April, 2008.     

Determination of Mesoscale Surface Currents in Shallow-Water Regions According to the Data of High-Frequency Radar Measurements

We propose a new method for the evaluation of the velocities of surface currents according to the data of measurements carried out by using high-frequency land-based radars. The method is based on the representation of the velocity fields via two scalar potentials, expansion of these potentials in series in basis functions, and determination of the coefficients of expansion according to the data of radar measurements as solutions of the corresponding variational problems. The errors of the procedure of determination of the coefficients of expansion are removed by using a special regularization procedure based on information theory. The proposed method enables one to fill gaps in the space and time series of radar measurements. We illustrate the method by an example of numerical analysis of mesoscale and submesoscale (10–50 km) surface currents in the Monterey Bay (California, USA) performed on the basis of the data of radar measurements carried out in August 1994. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 24–36, March–April, 2005.