Algorithm for the Diagnostics of Waves and Entropy Mode in the Exponentially Stratified Atmosphere

Leble, Sergey; Vereshchagin, S. D.; Vereshchagina, I. S.

doi:10.1134/s199079312002027x

“…The projecting technique was developed for a space-evolution operator, that allows to apply it to atmosphere parameters relations at a vicinity of a point of observation. It allowed to distinguish upand down-directed acoustic wave via the real dataset [17], in this work the algorithm of entropy mode diagnosis was elaborated, see also [18].…”

Section: Introductionmentioning

confidence: 99%

Diagnostic Relations Between Pressure and Entropy Perturbations for Acoustic and Entropy Modes

Leble¹,

Smirnova²

2021

Preprint

0

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Diagnostics and decomposition of atmospheric disturbances in a planar flow are considered and applied to numerical modeling results with the direct possibility to use in atmosphere monitoring especially in such strong events which follow magnetic storms. The study examines a situation in which the stationary equilibrium temperature of a gas may depend on a vertical coordinate, that seriously complicates the problem solution. The relations connecting perturbations for acoustic and entropy modes are analytically established and led to the solvable diagnostic equations. These perturbation structures, found as the equation solutions specify acoustic and entropy modes in an arbitrary stratified gas under the condition of stability. These time-independent diagnostic relations link gas perturbation variables of the acoustic and the entropy modes. Hence, they provide the ability to decompose the total vector of perturbations into acoustic and non-acoustic (entropy) parts uniquely at any instant within the all accessible heights range. As a prospective model, we consider the diagnostics at the height interval [120;180] km, where the equilibrium temperature of a gas depends linearly on the vertical coordinate. For such a heights range it is possible to proceed with analytical expressions for pressure and entropy perturbations of gas variables. Individual profiles of acoustic and entropy parts for some data, obtained by numerical experiment, are illustrated by the plots for the pure numerical data against ones obtained by the model. The total energy of a flow is determined for both approaches and its height profiles are compared.

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“…In algorithmic approach to mode definition [15,16], the method is formulated via projecting operators, that are defined for each evolution operator subspace. The projecting operators and their energy weight calculation are realized by means of an auxiliary norm introduction.…”

Section: Introductionmentioning

confidence: 99%

Study of a Gas Disturbance Mode Content Based on the Measurement of Atmospheric Parameters at the Heights of the Mesosphere and Lower Thermosphere

Leble

¹

,

Vereshchagin

²

,

Бахметьева

³

et al. 2021

Atmosphere

0

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The main result of this work is the estimation of the entropy mode accompanying a wave disturbance, observed at the atmosphere heights range of 90–120 km. The study is the direct continuation and development of recent results on diagnosis of the acoustic wave with the separation on direction of propagation. The estimation of the entropy mode contribution relies upon the measurements of the three dynamic variables (the temperature, density, and vertical velocity perturbations) of the neutral atmosphere measured by the method of the resonant scattering of radio waves on the artificial periodic irregularities of the ionospheric plasma. The measurement of the atmosphere dynamic parameters was carried out on the SURA heating facility. The mathematical foundation of the mode separation algorithm is based on the dynamic projection operators technique. The operators are constructed via the eigenvectors of the coordinate evolution operator of the transformed system of balance equations of the hydro-thermodynamics.

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“…We name the Eqs. (13,14) as diagnostic rela-120 tions, that define the acoustic and entropy mode in the 1D atmosphere with arbitrary 121 stratification.…”

mentioning

confidence: 99%

“…The model, used in this paper [29], is a numeric solution of the full two-dimensional non- According to the equations rhs (21,23) and the diagnostic equations (14,13), such a 141 study requires pressure and entropy data for constructing function f 0 (z), f a (z), where 142 the link of the variables P, Φ with original, pressure and density wave perturbations p 143 and ρ directly measured or calculated ones, are described by the relations ( 4) and ( 5).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Diagnostic Relations Between Pressure and Entropy Perturbations for Acoustic and Entropy Modes

Leble¹,

Smirnova²

2021

Preprint

0

View full text Add to dashboard Cite

Diagnostics and decomposition of atmospheric disturbances in a planar flow are considered and applied to numerical modeling results with the direct possibility to use in atmosphere monitoring especially in such strong events which follow magnetic storms. The study examines a situation in which the stationary equilibrium temperature of a gas may depend on a vertical coordinate, that seriously complicates the problem solution. The relations connecting perturbations for acoustic and entropy modes are analytically established and led to the solvable diagnostic equations. These perturbation structures, found as the equation solutions specify acoustic and entropy modes in an arbitrary stratified gas under the condition of stability. These time-independent diagnostic relations link gas perturbation variables of the acoustic and the entropy modes. Hence, they provide the ability to decompose the total vector of perturbations into acoustic and non-acoustic (entropy) parts uniquely at any instant within the all accessible heights range. As a prospective model, we consider the diagnostics at the height interval [120;180] km, where the equilibrium temperature of a gas depends linearly on the vertical coordinate. For such a heights range it is possible to proceed with analytical expressions for pressure and entropy perturbations of gas variables. Individual profiles of acoustic and entropy parts for some data, obtained by numerical experiment, are illustrated by the plots for the pure numerical data against ones obtained by the model. The total energy of a flow is determined for both approaches and its height profiles are compared.

show abstract

Algorithm for the Diagnostics of Waves and Entropy Mode in the Exponentially Stratified Atmosphere

Cited by 8 publications

References 9 publications

Diagnostic Relations Between Pressure and Entropy Perturbations for Acoustic and Entropy Modes

Diagnostic Relations Between Pressure and Entropy Perturbations for Acoustic and Entropy Modes

Study of a Gas Disturbance Mode Content Based on the Measurement of Atmospheric Parameters at the Heights of the Mesosphere and Lower Thermosphere

Diagnostic Relations Between Pressure and Entropy Perturbations for Acoustic and Entropy Modes

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