L. Kh. Ingel

Scientific and Production Association "Typhoon" | RPA Typhoon · Institute of Experimental Meteorology

A generalization of the Prandtl’s stationary model of slope flows taking into account the influence of Coriolis accelerations is considered. The helicity of stationary slope flows is calculated analytically. Calculations show that the helicity of such flows, in principle, can be very significant even at very small angles of inclination of the lower...

The linear stationary perturbations of horizontal stratified flows of an ideal medium caused by horizontally inhomogeneous volume sources of buoyancy have been studied analytically. Such problems have many applications including, in particular, geophysical ones. An example is the interaction of wind in the troposphere with the region of moist conve...

In the recent literature, attention has been drawn to the previously uninvestigated mechanism of the occurrence of flows in a stratified fluid in a gravity field. Such flows can occur in the absence of mechanical momentum and buoyancy sources due to horizontal inhomogeneity of transfer coefficients. For the first time, this investigation provides a...

There are indications that spatially inhomogeneous buoyancy forces can play a significant role in the dynamics of intense tornado-type atmospheric vortices. The paper considers a linearized model of disturbances caused by buoyancy deviations (in particular, inhomogeneously distributed heavy admixture) in an intense vortex with a vertical axis. Anal...

In recent theoretical studies of the authors, some estimates of the atmospheric disturbances related to inhomogeneities of the gravity field (IGF) have been obtained. The main attention was paid to dynamic effects: disturbances of the wind field under the influence of IGF. In this paper, attention is drawn to the fact that noticeable thermal effect...

The sensitivity of the results of calculations of the helicity of flows in the boundary layer of the atmosphere with respect to the nonstationarity factor and details of the description of turbulent exchange is theoretically studied. It is shown that often used estimates in the framework of the classical Ekman model can lead to significantly overes...

Theoretically, some features of the motion of inertial particles in a liquid/gaseous medium are studied with rapid fluctuations in the velocity of the medium, for example, during the passage of an acoustic wave. Unlike a number of previous studies, the case of sufficiently massive particles/droplets (large Reynolds numbers) in the air is considered...

In a number of recent publications, attention is drawn to the heterogeneity of the underlying surface as a factor that can contribute to the genesis and intensification of tornadoes. This paper proposes an analytical model for the generation of vorticity under the influence of horizontally inhomogeneous friction. The resulting vorticity is proporti...

The sensitivity of the results of calculating atmospheric flow helicity in the atmospheric boundary layer with respect to the factor of nonstationarity and details of the eddy exchange description is theoretically investigated. The study shows that estimates often used in the framework of the classical Ekman model can lead to significantly overesti...

The interaction of various forms of convection with stably stratified barrier layers in the atmosphere is theoretically investigated. Three different formulations of the problem are considered. 1) A linear problem with given perturbations of temperature and vertical velocity at the lower boundary of a stably stratified medium. 2) Penetration of an...

In a number of recent publications, attention is drawn to the heterogeneity of the underlying surface as a factor that can contribute to the initiation and intensification of tornadoes. The paper proposes an analytical model for the generation of vorticity under the influence of horizontally inhomogeneous friction. The resulting vorticity is propor...

Inhomogeneous friction on the underlying surface leads to horizontal divergence, vertical motions,and helicity generation. The significance of this mechanism is assessed by the analytical model that allowsone to establish some general patterns and estimate the amplitudes of the corresponding perturbations depending on the values of the parameters....

A linear stationary problem of the response of a semi-bounded stably stratified fluid/gaseous medium to volumetric spatially inhomogeneous heat release in the Boussinesq approximation is theoretically investigated. The most important similarity parameters are the analogue of the Rayleigh number and the aspect ratio of the source of buoyancy. For a...

Inhomogeneous friction on the underlying surface leads to horizontal divergence, vertical motions, and helicity generation. The paper presents an analytical model that allows one to establish some general laws and estimate the amplitudes of the corresponding perturbations depending on the values of the parameters. In particular, the possibility of...

A linear stationary problem of the response of a semi-bounded stably stratified fluid/gaseous medium to volumetric spatially inhomogeneous heat release in the Boussinesq approximation is theoretically investigated. The most important similarity parameters are the analogue of the Rayleigh number and the aspect ratio of the source of buoyancy. For a...

The nonlinear problem of the acceleration of heavy particle picked up by a fast flow in a gravity field is studied analytically. This problem is interesting, in particular, in connection with dangerous convective phenomena in the lower atmosphere (heavy wind gusts, tornadoes). Heavy particles/objects carried by intense winds are one of the main haz...

Keywords: snow cover, inhomogeneities of the gravity field, horizontal transport of a heavy admixture, analytical model. Summary A number of recent publications note the observed correlation of snow/ice thickness in some arctic regions with gravity field inhomogeneities. The physical mechanisms that could cause such a correlation are still unclear...

In recent theoretical works of the authors, some estimates of atmospheric disturbances associated with inhomogeneities of the gravity field (IGF) have been obtained. In this case, the main attention was paid to dynamic effects – disturbances of the wind field under the influence of IGF. In this work, attention is drawn to the fact that noticeable t...

Consideration has been given to a linear analytical model of perturbations of geostrophic flow of a stratified rotating medium resulting from the action of stationary sources of momentum and/or buoyancy. The problem formulation appears more consistent than the ones considered in the literature. The model makes it possible to evaluate explicitly the...

As is well known, flows in a free atmosphere outside a narrow equatorial zone are characterized by a geostrophic regime. For several applications, it is of interest to estimate the disturbances of the geostrophic wind caused by the action of sources of heat and/or momentum. One possible example is associated with manifestations of internal gravitat...

In this paper, we analytically study the mechanism of the onset of the liquid/gas flow in a non-isothermal stratified medium. The flow is induced by small spatial inhomogeneities of the exchange coefficients. In a statically stable stratified medium heated strictly from above, as is known, there is heat diffusion directed from top to bottom. We con...

In a liquid (gaseous) medium above a thermally inhomogeneous horizontal surface in a gravity field, convective flows arise, which can play an important role, in particular, in the dynamics of the atmosphere. An extensive literature is devoted to their theory, but, due to the complexity of the problem and the variety of possible combinations of para...

For a long time, seismologists considered various hydrometeorological signals as annoying hindrances to their main studies. However, in some circum' stances, seismic signals can be very useful for understanding hydrometeorological processes. Even more interesting is that the impact of such processes on the earth’s crust is quite noticeable. Nowaday...

Abstract: A two-dimensional stationary linear model of flows arising in a stably (neutral) stratified medium over a thermally inhomogeneous flat inclined surface is analyzed analytically. Temperature deviations that harmonically depend on the horizontal coordinate transverse to the slope are set at the lower boundary. Explicit analytical solutions...

A well-known simplified model of turbulent convection from local sources of buoyancy and/or momentum acting for a short time has been developed and generalized in a number of directions. The features of the dynamics of convection from finite-size sources are considered. The influence of the background flow with a vertical shear and the presence of...

The heterogeneities of the gravity field (HGF) deform the fields of air pressure, density, and temperature and affect the temperature regime of the boundary layer of the atmosphere, as well as the heat exchange between the air and the underlying surface. This work considers a stationary analytical model intended for estimation of the amplitudes of...

The convection that owes its origin to double (differential) diffusion in a rotating medium in the gravity force fi eld may lead, generally speaking, to transfer of vorticity, and, in particular, to its concentration. As a rule, this is not considered in geophysical applications, since the spatial and time scales of such a convection and of rotatio...

An extensive literature is devoted to the study of the boundary layer of the atmosphere over an inhomogeneous underlying surface. However, the specificity of anisotropic boundary layers, when the effective roughness and drag coefficient depend on the wind direction, has been studied to a much lesser extent. Such situations, in addition to cases of...

The splashes that occur at the surface of water bodies during strong winds significantly affect evaporation, exchange of heat and momentum, and the transfer of admixtures, such as salt aerosol, which affects clouds and precipitation. In this case, the height of the spray rise and the time it remains in the air play an important role. In the case of...

The authors focus on the following effect: near an inclined surface in a temperature (density) stratified turbulent medium in a gravity field, a regular flow along the slope should appear. This is due to the existence of a region of weakened turbulent exchange near the solid surface, in other words, to the appearance of spatial inhomogeneities of t...

The Prandtl model of slope flows (convection in a stratified medium near an inclined surface) has been generalized to the case of the presence of volume heat sources/sinks oriented in parallel with the slope. Such sources exist, for example, when an aerosol is present in the atmosphere that affects the radiation balance of the air. The properties o...

The well-known simplified model of turbulent convection from local sources of buoyancy and/or momentum acting for a short time is being developed and generalized in a number of directions. The features of convection from sources of finite sizes are considered. The effect of the background flow with a vertical shift and the presence of buoyancy sour...

In solving atmospheric dynamics problems, the influence of the gravity field inhomogeneities (GFI) is neglected. The traditional basis for this is that the amplitude of gravity variations even in highly anomalous regions do not exceed 10 ⁻³ ms ⁻² in order of magnitude, i.e. 4 orders of magnitude less than average gravity. But in the presence of gra...

Рассмотрена теоретическая модель циркуляций над термически неоднородной горизонтальной поверхностью в поле силы тяжести, более общая, чем в ряде предыдущих работ. Модель свободна от предположения об относительной тонкости экмановского пограничного слоя, которое (будучи не всегда обоснованным) существенно упрощало расчеты, поскольку с ним связывалос...

A theoretical problem on linear stationary disturbances introduced by spatial inhomogeneities of gravity field into the background geostrophic flow of the stratified rotating medium (atmosphere) is considered. For the first time, the three-dimensional analytical model is considered. Our results imply that inhomogeneities of the gravity field can le...

In systems consisting of two immiscible liquids in the gravity force field, convective instability may set in not only on heating from below, but also on horizontal-homogeneous heating from above, i.e., on stable density stratification of each of the media. In a number of previous works, a linear theory of this type of instability ("anticonvections...

Proceedings of A.I. Voeikov Main Geophysical Observatory Issue 594. 2019. P. 95-106. TO ESTIMATION THE RESPONSES OF THE ATMOSPHERE ON LOCAL THERMAL AND DYNAMIC IMPACTS (in Russian) L. Kh. Ingel Research and Production Association “Typhoon”, Obninsk, 249038, Russia Obukhov Institute of Atmospheric Physics, RAS, Moscow, 119017, Russia Interdepartm...

By using the methods of scale analysis, dimensional analysis, and of the symmetry of differential equations, the dynamics of buoyant convective jets connected with stationary, local sources of a weightless heat-releasing impurity in a neutrally stratified medium is investigated. An example of such an impurity is an aerosol that absorbs solar radiat...

The stability of the state of rest of a liquid medium in a gravitational field has been studied in a linear approximation. The density of the medium is linearly dependent on temperature and on the concentration of an admixture. In the background state, the admixture is distributed uniformly, and the temperature stratification is stable (the density...

Convection caused by the double (differential) diffusion in a rotating medium can lead to a transfer of vorticity, and in particular, to its concentration. In geophysical applications, it is not considered usually, because the spatial and temporal scales of such convection and rotation effects differ greatly – the period of planetary rotation is ma...

2 Институт физики атмосферы им. А.М. Обухова РАН, г. Москва, Россия 3 Межведомственный центр аналитических исследований в области физики, химии и биологии при Президиуме РАН, г. Москва, Россия В современных моделях геофизической гидродинамики поле силы тяжести обычно считает-ся однородным и описывается с использованием одного параметра. Между тем и...

Convection induced by double (differential) diffusion in a rotating medium can generally lead to the transfer of vorticity and, in particular, to its concentration. In geophysical applications, this situation is not usually considered because the spatial and temporal scales of such convection and of rotation effects differ significantly: the period...

Often used model of turbulent convection from localized sources of buoyancy and (or) momentum acting for a short time – isolated thermals. In such a model, the perturbation region (thermal) is approximately represented as a “bubble” or a vortex ring of variable volume and mass that rises (or descends depending on the perturbation sign). The volume...

Some physical mechanisms of perturbations of the wind field due to the inhomogeneities of gravity field have been established. The simplest analytical models of stationary linear atmospheric disturbances caused by inhomogeneities in the field of gravity are analyzed. Estimates show that the influence of gravitational force anomalies (GFAs) on the f...

The known nonlinear integral model of a turbulent thermal is generalized to the case of the presence of the horizontal component of its motion relative to the surrounding medium (for example, the floating-up of a thermal in a shear flow). In addition, the possibility of the presence of a heat (buoyancy) source in a thermal is considered. In compari...

One possible mechanism for the effect of gravity-field inhomogeneities (GFIs) on the atmosphere dynamics has been investigated theoretically. It is shown that the vertical heat exchange in an air layer in an inhomogeneous gravity field can disrupt the state of hydrostatic equilibrium and lead to the generation of vortex flows. Estimates of the ampl...

A Prandtl slope flow model is generalized for the case with a homogeneous stationary source of a heavy admixture that significantly changes the medium density. A stationary analytical solution for a velocity of arising flows, temperature deviations, and admixture distribution is obtained. The model describes, for example, some special features of t...

Paradoxical properties of the classical Prandtl solution for flows occurring in a semibounded liquid (gaseous) medium above an infinite homogeneously cooled/heated inclined plane are analyzed. In particular, the maximum velocity of steady-state slope flow is independent, according to this solution, of the angle of inclination. Consequently, there i...

The nonlinear integral model of a turbulent thermal is extended to the case of the horizontal component of its motion relative to the medium (e.g., thermal floating-up in shear flow). In contrast to traditional models, the possibility of a heat source in the thermal is taken into account. For a piecewise constant vertical profile of the horizontal...

The recent experience of implementing statistical forecast of some classes of severe convective thunderstorms is described: strong winds, intense hails, tornadoes (J.A. Hart, A. E. Cohen, USA).

The author presents results of theoretical assessments referring to the convection that appears above a "cold spot" on a horizontal surface. Consideration is given to the case of thermal inhomogeneities with a fairly large amplitude where one cannot restrict oneself to a linear approximation. An analog of the Rayleigh number proportional to the amp...

Steady perturbations introduced into a temperature-stratified fluid binary mixture, such as saline water, by inhomogeneous tangent stresses on its surface have been studied in a linear approximation. It has been shown that thermodiffusion may greatly increase the depth of thermal perturbation penetration into the medium despite the stable backgroun...

The author presents results of theoretical assessments referring to the convection that appears above a "cold spot" on a horizontal surface. Consideration is given to the case of thermal inhomogeneities with a fairly large amplitude where one cannot restrict oneself to a linear approximation. An analog of the Rayleigh number proportional to the amp...

The basic concepts, information and methods for studying the influence of inhomogeneities (anomalies) of the gravity field on the dynamics of the atmosphere are briefly considered. The basis of these theoretical studies is the obtaining of analytical expressions for linear perturbations caused in the fields of meteorological quantities by inhomogen...

Taking into account the heat exchange, the horizontal inhomogeneities of the gravity field were shown to lead to the origin of dynamic perturbations (flows) in the density stratified medium. The amplitude of the horizontal component of the originating flows is proportional to the product of a geoid deviation from a uniform Earth ellipsoid and buoya...

The theoretical problem of linear stationary disturbances introduced into the background geostrophic flow of a stratified rotating medium (atmosphere) by the spatial inhomogeneities of the gravity field is considered. It is widely believed that such inhomogeneities can only deform (distort) the state of hydrostatic equilibrium, but do not affect th...

A theoretical problem of linear stationary disturbances of the background geostrophic flow of a stratified rotating medium (atmosphere) that are induced by inhomogeneities of the gravitational field is considered. There is a common belief that such inhomogeneities may only somewhat deform (distort) the state of hydrostatic equilibrium, but cannot a...

The horizontal movement of the inertial particles in the intense vortices, in which the centrifugal force can be substantially higher than the force of gravity, is studied analytically. Earlier, a similar problem was studied for small (“Stokes’ “) particles at low values of the Reynolds number, at which one can be limited to the linear resistance l...

The horizontal movement of inertial particles in the intensive vortices, where the centrifugal force can be substantially higher than the gravity, is studied analytically. A similar problem was studied earlier for small (Stokes) particles at low Reynolds number, which allow one to be limited to the linear resistance law. It is shown that the previo...

It is shown that inhomogeneities in gravity field affecting the horizontal wind may cause the generation of internal gravity waves in atmosphere. The simple analytical model is considered and theoretical estimates of characteristics of such wave are obtained.

When a heavy particle moves in a viscous medium, the resistance force depends on the Reynolds number, therefore, on the modulus of the particle velocity vector in relation to medium. This leads to nonlinear interaction of different components of movement. If a particle settling in gravity field has also a horizontal velocity component, these two co...

Examples are presented of an exact solution of a nonstationary problem on the development of convection in a binary mixture (seawater) near an infinite vertical surface in which the buoyancy disturbances are determined both by the temperature and by the disturbances of the impurity (salt) concentration. Consideration is given to the development of...

Abstract⎯In traditional theoretical models of convection from isolated sources, results usually depend little on their sizes: convective jets and isolated thermals rapidly “forget” the source geometry. However, new problems in which the sizes of a source are relatively large and can significantly influence results have recently become important. Th...

The critical comments to the publications by the authors of the present paper that were given in [10] (the publications deal with the possible effects of gravity field inhomogeneities in the atmosphere and ocean) are discussed. In the authors’ opinion, some remarks are ground less. At the same time, the authors agree with one of the important remar...

The problem of a response from a stably stratified fluid to the action of vertically extended harmonic heat and momentum sources is solved analytically. Emphasis is on the high sensitivity of such fluids to actions with frequencies close to the buoyancy frequency. This result can find a number of applications.

An approximate analytical solution of the one-dimensional problem of steady oscillations of a rotating viscous fluid subjected to harmonic-in-time shear stresses on the horizontal boundary is derived. The solution demonstrates the resonance amplification of the oscillation amplitude and the depth of their penetration into the fluid as the excitatio...

Using the simple analytic model, the linear stationary disturbances of geostrophic flow induced by gravity field inhomogeneities are studied. The analysis demonstrated that the effects of the above inhomogeneities can be significant.

Abstract—Linear disturbances induced by gravity�-field inhomogeneities in a horizontal stratified flow with a vertical shear are calculated analytically. In addition to being dependent on the amplitude of these inhomo� geneities, disturbances depend strongly on their horizontal scales, background flow velocity, stratification, and Coriolis paramete...

Evaluation of ice-forming particle transport from ground-based generators in hail protection and precipitation modifying operations L. Dinevich, L.Kh. Ingel, A. Khain 1 George S. Wise Faculty of Natural Sciences, Dept. of Zoology, Tel-Aviv University, Ramat Aviv, 69978, Israel. Tel/fax +972-640-60-10, dinevich@013.net 2 Federal State Budgetary Ins...

Аналитически рассчитаны линейные возмущения, вызываемые неоднородностями поля силы тяжести в горизонтальном стратифицированном течении с вертикальным сдвигом. Найденные решения показывают, что в определенных ситуациях влияние аномалий силы тяжести на атмосферные течения может быть заметным. Анализируются физические механизмы генерации возмущений.

The response of a semi-infinite stratified rotating medium to the action of an inhomogeneous vortex shearing stress on a horizontal surface is investigated analytically in a linear approximation. The previously unexplored region of the values of governing parameters is considered. It has been established that in the fi rst approximation the indicat...

Linear disturbances induced by gravity-field inhomogeneities in a horizontal stratified flow with a vertical shear are calculated analytically. In addition to being dependent on the amplitude of these inhomogeneities, disturbances depend strongly on their horizontal scales, background flow velocity, stratification, and Coriolis parameter. The most...

Attention is focused on a positive feedback that may play a significant role in intense vortices, such as tornadoes and, probably, tropical cyclones: rotation suppresses turbulence which, in turn, may intensify rotation. Some simple models illustrate this phenomenon.