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Using satellite data, connections between the North Atlantic Oscillation (NAO) and the daily anomalies in total column ozone (TCO) and those in precipitable water vapor (PWV) over Europe during the summer of 2010 heatwave were analyzed. The analysis revealed over the northern European Russia (ER) spacious and closely located regions of negative correlation between TCO and NAO and positive correlation between PWV and NAO, with the extreme (maximum) local correlation coefficients up to -0.55 and 0.68, respectively. The results of correlation analysis and cross-wavelet analysis showed that the increased correlations between TCO, PWV, and NAO in the summer of 2010 were mainly due to coherent variations of atmospheric parameters in the period of the destruction of blocking anticyclone.

Non-stationary mathematical model of bioaerosol dynamics is considered. It is based on nonlinear integral-differential equations describing coagulation, condensation, and evaporation processes. Unconditionally positive numerical schemes for transformation problem is presented. The algorithm is based on discrete analytical approximations using fundamental solutions of local ajoint problems. The model was numerically compared with the models describing individual mechanisms in its composition. The relative contribution of each mechanism in the overall dynamics of aerosol populations is investigated based on numerical experiments.

Using a numerical mesoscale model of the atmospheric boundary layer the dynamics of air streams in the Norilsk valley is investigated. Results of calculations for typical weather conditions are presented. It is shown that the orographic peculiarities of the region form a wind field, nonhomogeneous in the horizontal and highly variable in the vertical. With data on pollution of the snow cover in vicinity of the Norilsk copper plant a numerical reconstruction of fields of dust and heavy metals sedimentation is carried out.

Saltation mechanism investigation in the windsand flux over the desertified area has been carried out on fast video recording data using spectral and wavelet analysis. Quasiperiodic variation peculiarities of the saltating sand concentration are studied. It is established that narrow bands in spectrum (“spectral lines”) of saltating sand concentration fluctuation density power in the range from 100 to 200 Hz are consistent with wave packets, which duration achieves 8-9 periods. It is suggested to use the duration of the wave packets observed as a measure of a pulsation coherence of the wind velocity in a near surface layer of the atmosphere. It is shown that quasiperiodic variability saltating sand concentration appearance is explained by interaction of the wind gusts with wave irregularities on the underlying surface type of fine ripples. The wave packet formation with duration to 4-5 periods can be explained using the model of jet-pulse saltation.

The stationary motion of a large spherical aerosol particle in the external field of a temperature gradient in zero gravity is theoretically described using the Stokes approximation and the assumption that the average temperature of the particle surface differs considerably from the temperature of the surrounding gaseous medium. The gas dynamics equations are solved taking into account the power-law temperature dependence of the molecular transport coefficients (viscosity, thermal conductivity) and the density of the gaseous medium. Numerical estimates show that the dependence of the thermophoretic force and velocity on the average temperature of the particle surface is nonlinear.

This paper describes the thermal convection and heat transfer in a cylindrical fluid layer rotating around a horizontal axis, with various constant temperatures set at the layer boundaries. The influence of the rotational speed of the cylindrical fluid layer on the convective heat transfer in this layer is studied. The study results are presented according to the dimensionless parameters that characterize the action of two convective mechanisms: centrifugal and thermal-oscillatory. It is shown that, with low rotational speed, the heat transfer is determined by quasistationary gravitational convection.

This paper presents the results of an experimental study of the deformation and structural parameters of 1561 anisotropic alloy. It has been found that the lowest anisotropy factor corresponds to the formation of an ultrafine-grained equiaxed structure under temperature-strain rate conditions of superplasticity.

A two-dimensional contact problem of a trapezium shaped punch pressed into a frictionless, elastically similar half-plane and subject sequentially to the normal load and bending moment is considered. The model of a tilted flat punch is used to evaluate the pressure distribution and the contact deformation within the contact zone. Comparisons of the results generated by the analytical technique to those computed by the finite element method demonstrate the high level of accuracy attained by both methods. The presented numerical results illustrate the effects of the normal load, bending moment, and internal angles of the punch geometry on the contact stresses.

The strain-strength characteristics of aerostructures made of hardening materials under uniaxial tension in creep conditions are determined. The problem is reduced to a system of ordinary differential equations of the kinetic theory of creep with one scalar damage parameter. The approximate solutions of the problem are obtained with the help of the implicit Euler method and of the arc length method in combination with the explicit methods of the Runge-Kutta family for cylindrical St.45 steel samples and 3V titanium alloy plates.

The aim of the present research is to conduct a numerical study of the characteristic of a two-phase magnetorheological fluid with different operation conditions by the finite volume method called SIMPLE with an add-on MHD code.