Vol 55, No 4 (2019)

ARTICLES

Vertical propagation acoustic-gravity waves from atmospheric fronts into the upper atmosphere

Kurdyaeva Y.A., Kulichkov S.N., Kshevetskii S.P., Borchevkina O.P., Golikova E.V.

Abstract

Using experimental observations of atmospheric pressure variations on the Earth’s surface recorded with a network of 4 microbarographs located in the Moscow region during the passage of an atmospheric front, empirical approximations of oscillations of atmospheric pressure field were constructed. The obtained approximating functions were used as the lower boundary condition for the numerical simulation of acoustic-gravity wave propagation to the upper atmosphere from the source in the lower troposphere. Estimates of the amplitude of temperature disturbances in the upper atmosphere caused by iacoustic gravity waves from the atmospheric front are given. The obtained estimates for the temperature disturbance amplitude take values around 170 K. The amplitude of temperature disturbances in the upper atmosphere, caused by background variations of pressure on the Earth's surface, is estimated at 4-5 K.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):3-12
pages 3-12 views

The layered structure of stably stratified turbulent shear flows

Glazunov A.V., Mortikov E.V., Barskov K.V., Kadancev E.V., Zilitinkevich S.S.

Abstract

The data of numerical simulation of stably stratified turbulent Couette flows are analyzed for various values of the Richardson number. Two different methods were used: Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES). It is shown that the flow contains large organized structures, along with chaotic turbulence, regardless of the simulation method. These structures appear as inclined layers in the temperature field with weakly stable stratification, separated by very thin layers with large temperature gradients. The existence of such layered structures in nature is indirectly confirmed by the analysis of field measurement data on the meteorological mast, where temperature gradient distribution histograms are found to be far from the normal distribution and similar to temperature gradient probability distributions obtained by numerical models data. The simulations indicate an increase of the turbulent Prandtl number with increasing of the gradient Richardson number. It is highly likely that the identified structures serve as effective barriers for vertical turbulent heat flux, without the blocking of momentum transfer. We proposed the hypothesis, that it is precisely these structures that serve as the physical mechanism for maintaining turbulence under supercritically stable stratification.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):13-26
pages 13-26 views

Properties of the frequency spectra of the temperature anomalies of ocean surface and near-surface air in a simple stochastic climate model with fluctuating parameters

Petrov D.A.

Abstract

The frequency properties of the ocean surface temperature anomalies (SST) and near-surface air (SAT) spectra are analyzed on the basis of a simple energy balance model of the climate, taking into account the fluctuations of the radiation balance, the latent and sensible heat flux and the velocity of the near-surface wind in two particular cases when the statistical properties of the model parameters are the white noise (small-scale-mesoscale subintervals) and the combined case when the properties of the synoptic subinterval of this parameters are taken into account in the SAT block. It was found that in the first case, the spectra have no features, and in the second they contain selected frequencies in the synoptic and low- frequency intervals. The dependent of their frequencies on model parameters are analyzed. The properties of standard deviations of SST and SAT are investigated.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):27-36
pages 27-36 views

100,000-year rhythmicity in glacial cycles and global sea level variations

Bezverkhnii V.A.

Abstract

100,000-year rhythmicity of paleoclimate variations, that aroused in the Late Pleistocene, can be linked with corresponded long-term oscillations of insolation and seafloor volcanism, forced by gravitational forces in Solar system. This conclusion is based on wavelet analysis of variations of the earth’s orbit eccentricity, different paleoclimatic characteristics, and their known spectral estimates and seafloor volcanism data.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):37-44
pages 37-44 views

On one peculiarity of the dynamics of intensity tropical cyclones operating as a group

Yaroshevich M.I.

Abstract

The groups of tropical cyclones are considered. A group is understood as a totality of cyclones, more-less coinciding with each other in time. In each group, the main cyclone is the most intense. The nature of the intensity and dynamics distributions of the group cyclones relative to the main cyclone is determined.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):45-48
pages 45-48 views

Modeling of atmospheric disturbances above the Crimean mountains

Kozhevnikov V.N.

Abstract

While using the non-linear analytical model of the flow over the mountains, orographic disturbances and the model adequacy were studied. Theoretically calculated trajectories, disturbances of temperature and humidity were compared with the actual stereophotogrammetric measurements of wavy clouds. It was shown that the model successfully describes the spatial structure and amplitudes of disturbances in the troposphere beyond the turbulent surface air. It was established that, on the days of clouds observations, turbulent processes in the surface air did not have any significant impact on wavy processes at the heights over 2.5 km.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):49-57
pages 49-57 views

Validation of GNSS data about the integrated water vapor in Europe using sun photometers

Kalinnikov V.V., Khutorova O.G.

Abstract

In the article the comparison of time series of integrated water vapor (IWV) for 2015-2017 at 8 pair stations of GNSS and solar photometers of AERONET network in Europe is carried out. The distance between pairs of stations didn’t exceed 20 km. It is shown that bias and standard deviations of divergences have the seasonal course. In the winter GNSS-photometer bias was from –0.61 to 0.34 mm. In the summer the GNSS overestimates IWV relative to photometers by values from 0.52 to 2.26 mm. The standard deviation is maximal in summer and is from 1.31 to 1.64 mm, in winter it decreases to 0.49-0.86 mm that is 5-6% of IWV.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):58-63
pages 58-63 views

Subpollen particles as atmospheric cloud condensation nuclei

Mikhailov E.F., Ivanova O.A., Nebosko E.Y., Vlasenko S.S., Ryshkevich T.I.

Abstract

Bioparticles represent a significant fraction of the total atmospheric aerosol. Their size range varies from nanometers (macromolecules) to hundreds of micrometers (plant pollen, vegetation residues) and like other atmospheric aerosol particles, the degree of involvement of bioaerosols in atmospheric processes largely de- pends on their hygroscopic and cloud condensation nuclei properties. In this paper the ability of the pine, birch and rape subpollen particles to act as cloud condensation nuclei are considered. Submicron particles were obtained by aqueous extraction of biological material from pollen grains and subsequent solidification of the atomized liquid droplets. The parameters of cloud activation are determined in the size range of 20-270 nm in the range of water vapor supersaturations 0.1-1.1%. Based on experimental results, the hygroscopicity parameter, characterizing the effect of the chemical composition of the subparticles on their con- densation properties, is determined. The range of the hygroscopic parameter changes was 0.12-0.13. In general, the results of measurements showed that the condensation activity of the subpollen particles is comparable with the condensation activity of secondary organic aerosols and weakly depends on the type of the primary pollen.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):64-72
pages 64-72 views

Meridional mass transport of bottom water in the South Atlantic

Belyaev K.P., Morozov E.G., Tuchkova N.P.

Abstract

Estimates of the meridional mass transport of Antarctic Bottom Water, calculated using the coupled ocean- atmosphere model called “Earth System Model” in conjunction with the original data assimilation method are presented. We used the data of the latitudinal CTD sections of temperature and salinity of the WOCE international experiment in 1991-1995 for assimilation. Estimates of the current velocities of Antarctic Bottom Water with the assimilation of observational data are given. We used the author’s data assimilation method, which was previously referred as the generalized Kalman Filter (GKF) method. In the particular case it coincides with the classical Kalman method (EnKF). We also analyze the estimates of the mass transport by the standard dynamic scheme. It is shown that model calculations with data assimilation are qualitatively the same and are quantitatively close to the estimates of geostrophic flow transport based on the dynamic method.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):73-81
pages 73-81 views

The influence of nonlinear interaction on the evolution of waves in a shallow basin

Rodin A.A., Rodina N.A., Kurkin A.A., Pelinovsky E.N.

Abstract

The influence of counter interaction of nonlinear wave in the shallow water has been studied. It is shown that such an interaction leads to a change in the phase of propagation of the main wave, which is forced to propagate along the flow induced by the counter-propagating wave. Estimates of the height of the non-breaking wave at the moment of interaction are in agreement with theoretical predictions. The phase shift in the interaction of non-breaking waves is small enough, but becomes noticeable in the case of the breaking waves motion.

Известия Российской академии наук. Физика атмосферы и океана. 2019;55(4):82-86
pages 82-86 views

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