Russian State Hydrometeorological University

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Saint Petersburg, Russia

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Loginov A.V.,Russian State Hydrometeorological University
Optics and Spectroscopy (English translation of Optika i Spektroskopiya) | Year: 2017

The probabilities of radiative electric dipole transitions 2p53p, 2p6–2p53s, and 2p53d in the spectrum of neon-like copper Cu XX and 5p56p, 5p6–5p56s, 5p57s, and 5p55d in the spectrum of xenon-like lanthanum La IV are calculated. The wave functions of the intermediate coupling were found from the wellknown experimental energy levels by the least-squares method (LSM). To transfer to an absolute scale the radial integrals for the transitions calculated in the form of a length on the Hartree–Fock functions have been used. By summing the calculated probabilities of the transitions, the lifetimes of the levels of configurations 2p53s, 2p53p, and 2p53d in the spectrum of Cu XX and levels of configurations 5p56s, 5p56p, and 5p57s in the spectrum of La IV have been obtained. © 2017, Pleiades Publishing, Ltd.


Bulgakov K.Y.,Russian State Hydrometeorological University
Physics of Wave Phenomena | Year: 2017

The shallow-water propagation of a nonlinear wave formed in deep water has been numerically analyzed based on the conformal model of surface waves. The lifetime of wave until its collapse is investigated. The parameters at which extreme waves may occur are found. An example of practical application of the simulation results is presented. © 2017, Allerton Press, Inc.


Grant
Agency: European Commission | Branch: FP7 | Program: CP-IP-SICA | Phase: OCEAN.2011-4 | Award Amount: 11.32M | Year: 2012

Environmental policies focus on protecting habitats valuable for their biodiversity, as well as producing energy in cleaner ways. The establishment of Marine Protected Area (MPA) networks and installing Offshore Wind Farms (OWF) are important ways to achieve these goals. The protection and management of marine biodiversity has focused on placing MPAs in areas important for biodiversity. This has proved successful within the MPAs, but had little impact beyond their boundaries. In the highly populated Mediterranean and the Black Seas, bordered by many range states, the declaration of extensive MPAs is unlikely at present, so limiting the bearing of protection. The establishment of MPAs networks can cope with this obstacle but, to be effective, such networks must be based on solid scientific knowledge and properly managed (not merely paper parks). OWF, meanwhile, must be placed where the winds are suitable for producing power, but they should not have any significant impact on biodiversity and ecosystem functioning, or on human activities. The project will have two main themes: 1 - identify prospective networks of existing or potential MPAs in the Mediterranean and the Black Seas, shifting from a local perspective (centred on single MPAs) to the regional level (network of MPAs) and finally the basin scale (network of networks). The identification of the physical and biological connections among MPAs will elucidate the patterns and processes of biodiversity distribution. Measures to improve protection schemes will be suggested, based on maintaining effective exchanges (biological and hydrological) between protected areas. The national coastal focus of existing MPAs will be widened to both off shore and deep sea habitats, incorporating them into the networks through examination of current legislation, to find legal solutions to set up transboundary MPAs. 2 - explore where OWF might be established, producing an enriched wind atlas both for the Mediterranean and the Black Seas. OWF locations will avoid too sensitive habitats but the possibility for them to act as stepping-stones through MPAs, without interfering much with human activities, will be evaluated. Socioeconomic studies employing ecosystem services valuation methods to develop sustainable approaches for both MPA and OWF development will also be carried out, to complement the ecological and technological parts of the project, so as to provide guidelines to design, manage and monitor networks of MPAs and OWF. Two pilot projects (one in the Mediterranean Sea and one in the Black Sea) will test in the field the assumptions of theoretical approaches, based on previous knowledge, to find emerging properties in what we already know, in the light of the needs of the project. The project covers many countries and involves researchers across a vast array of subjects, in order to achieve a much-needed holistic approach to environmental protection. It will help to integrate the Mediterranean and Black Seas scientific communities through intense collective activities, combined with strong communications with stakeholders and the public at large. Consequently, the project will create a permanent network of excellent researchers (with cross fertilization and further capacity building) that will also work together also in the future, making their expertise available to their countries and to the European Union.


Sofiev M.,Finnish Meteorological Institute | Ermakova T.,Russian State Hydrometeorological University | Vankevich R.,Russian State Hydrometeorological University
Atmospheric Chemistry and Physics | Year: 2012

A new methodology for the estimation of smoke-injection height from wild-land fires is proposed and evaluated. It is demonstrated that the approaches developed for estimating the plume rise from stacks, such as the formulas of G. Briggs, can be formally written in terms characterising the wild-land fires: fire energy, size and temperature. However, these semi-empirical methods still perform quite poorly because the physical processes controlling the uplift of the wildfire plumes differ from those controlling the plume rise from stacks. The proposed new methodology considers wildfire plumes in a way similar to Convective Available Potential Energy (CAPE) computations. The new formulations are applied to a dataset collected within the MISR Plume Height Project for about 2000 fire plumes in North America and Siberia. The estimates of the new method are compared with remote-sensing observations of the plume top by the MISR instrument, with two versions of the Briggs' plume-rise formulas, with the 1-D plume-rise model BUOYANT, and with the prescribed plume-top position (the approach widely used in dispersion modelling). The new method has performed significantly better than all these approaches. For two-thirds of the cases, its predictions deviated from the MISR observations by less than 500 m, which is the uncertainty of the observations themselves. It is shown that the fraction of "good" predictions is much higher (>80%) for the plumes reaching the free troposphere. © 2012 Author(s).


Gogoberidze G.,Russian State Hydrometeorological University
Journal of Coastal Conservation | Year: 2012

For elaboration of strategy and spatial planning of sustainable coastal regions development it's very important to know a real potential of development of the region. As parameter, which is comprehensively characterized marine economic, political and military power of the coastal region, it is possible to use the marine economy potential with comprehensive estimations of socio-economic, political, environment and military profits (damages) from coastal planning decisions. Some results, including the European and Russian coastal regions are presented. © 2011 Springer Science+Business Media B.V.


Badulin S.I.,Russian State Hydrometeorological University | Grigorieva V.G.,RAS Shirshov Institute of Oceanology
Journal of Geophysical Research: Oceans | Year: 2012

The global visual wave observations are reanalyzed within the theoretical concept of self-similar wind-driven seas. The core of the analysis is one-parametric dependencies of wave height on wave period. Theoretically, wind-driven seas are governed by power-like laws with exponents close to Toba's one 3/2 while the corresponding swell exponent (-1/2) has an opposite signature. This simple criterion was used and appeared to be adequate to the problem of swell and wind-driven waves discrimination. This theoretically based discrimination does not follow exactly the Voluntary Observing Ship (VOS) data. This important issue is considered both in the context of methodology of obtaining VOS data and within the physics of wind waves. The results are detailed for global estimates and for analysis of particular areas of the Pacific Ocean. Prospects of further studies are discussed. In particular, satellite data are seen to be promising for tracking ocean swell and for studies of physical mechanisms of its evolution. © 2012. American Geophysical Union. All Rights Reserved.


Kudryavtsev V.N.,Russian State Hydrometeorological University | Makin V.K.,Royal Netherlands Meteorological Institute
Boundary-Layer Meteorology | Year: 2011

The impact of ocean spray on the dynamics of the marine near-surface air boundary layer (MABL) in conditions of very high (hurricane) wind speeds is investigated. Toward this end, a model of the MABL in the presence of sea-spume droplets is developed. The model is based on the classical theory of the motion of suspended particles in a turbulent flow, where the mass concentration of droplets is not mandatory small. Description of the spume-droplet generation assumes that they, being torn off from breaking waves, are injected in the form of a jet of spray into the airflow at the altitude of breaking wave crests. The droplets affect the boundary-layer dynamics in two ways: via the direct impact of droplets on the airflow momentum forming the so-called spray force, and via the impact of droplets on the turbulent mixing through stratification. The latter is parametrized applying the Monin-Obukhov similarity theory. It is found that the dominant impact of droplets on the MABL dynamics appears through the action of the 'spray force' originated from the interaction of the 'rain of spray' with the wind velocity shear, while the efficiency of the stratification mechanism is weaker. The effect of spray leads to an increase in the wind velocity and suppression of the turbulent wind stress in the MABL. The key issue of the model is a proper description of the spume-droplet generation. It is shown that, after the spume-droplet generation is fitted to the observations, the MABL model is capable of reproducing the fundamental experimental finding-the suppression of the surface drag at very high wind speeds. We found that, at very high wind speeds, a thin part of the surface layer adjacent to the surface turns into regime of limited saturation with the spume droplets, resulting in the levelling off of the friction velocity and decrease of the drag coefficient as U -2 10, U 10 being the wind speed at 10-m height. © 2011 The Author(s).


Kourzeneva E.,Russian State Hydrometeorological University
Boreal Environment Research | Year: 2010

Lake parameterizations in atmospheric modeling include a set of external data to indicate and to map physical properties of lakes. The main challenge is the need to consider all the lakes in the atmospheric model domain and to specify the corresponding parameters. For Numerical Weather Prediction (NWP), we also need the data to initialize the lake time-dependent variables (so-called cold start data). The first steps to make the set of lake parameters for the needs of atmospheric modeling are described in this paper. The mean lake depth was chosen to be the key lake parameter for which direct measurements were collected and processed. The Global Land Cover Characteristics (GLCC) dataset was used for mapping, and the mapping method was based on a probabilistic approach. Empirical Probability Density Functions were used to project the lake information onto the target grid of an atmospheric model. The pseudo-periodical regime of the lake model was used to obtain the initial fields of lake variables. © 2010.


Badulin S.I.,Russian State Hydrometeorological University
Journal of Geophysical Research: Oceans | Year: 2014

A physical model for sea wave period from altimeter data is presented. Physical roots of the model are in recent advances of the theory of weak turbulence of wind-driven waves that predicts the link of instant wave energy to instant energy flux to/from waves. The model operates with wave height and its spatial derivative and does not refer to normalized radar cross-section σ0 measured by the altimeter. Thus, the resulting formula for wave period does not contain any empirical parameters and does not require features of particular satellite altimeter or any calibration for specific region of measurements. A single case study illustrates consistency of the new approach with previously proposed empirical models in terms of estimates of wave periods and their statistical distributions. The paper brings attention to the possible corruption of dynamical parameters such as wave steepness or energy fluxes to/from waves when using the empirical approaches. Applications of the new model to the studies of sea wave dynamics are discussed. Key Points A physical model for sea wave period from altimeter data is presented The resulting formula for wave period does not contain any empirical parameters Relevance of the new model is shown in a case study © 2014. American Geophysical Union. All Rights Reserved.


Zabolotskikh E.V.,Russian State Hydrometeorological University | Mitnik L.M.,RAS Ilichev Pacific Oceanological Institute | Chapron B.,French Research Institute for Exploitation of the Sea
Geophysical Research Letters | Year: 2013

A methodology, based on model simulations and neural networks inversion, is proposed to jointly retrieve sea surface wind speed, sea surface temperature, atmospheric water vapor content, cloud liquid water content, and total atmospheric absorption at 10.65 GHz using Advanced Microwave Scanning Radiometer 2 measurements. In particular, estimation of the total atmospheric absorption at 10.65 GHz, which can be done with high accuracy due to the not so strong influence of liquid water and especially water vapor, helps to refine a new filter to considerably reduce masking ocean areas for severe weather systems, characterized by high wind speeds and moderate atmospheric absorption, appropriate for studying winter extratropical cyclone and polar low systems. A polar low case study has demonstrated significant improvement in the coverage of the ocean area available for geophysical retrievals: Only less than 1% of high wind speed pixels were masked comparatively to the 40-70% masking given by other methods. Key Points Algorithm for atmospheric absorption retrieval from AMSR2 data is developed Threshold value on atmospheric absorption can be used for severe weather masking New weather masking can significantly improve ocean retrieval coverage ©2013. American Geophysical Union. All Rights Reserved.

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