S. L. Odintsov

Structure functions of air temperature over an inhomogeneous underlying surface. Part II. Statistics of structure functions’ parameters

The statistics of parameters entering into analytical representations of air temperature structure functions in the ground layer of the atmosphere over an inhomogeneous underlying surface is presented. Our main attention is paid to the analysis of histograms of these parameters. One can see a rather high degree of variability in the parameters, which is related, in particular, to where the observations are performed and the height of the measuring device. The connection between structure function parameters and root-meansquare deviations of wind velocity and air temperature is considered.

Structure functions of air temperature over an inhomogeneous underlying surface. Part I. Typical forms of structure functions

Results of the analysis of air temperature structure functions in the ground layer of the atmosphere over an inhomogeneous underlying surface are presented. Based on processing of experimental data, three main types of structure functions are distinguished and models of their parameterization in the range of shifts related to the inertial turbulence interval are proposed. Repeatability of the distinguished types of structure functions in different seasons at the observation point over an urbanized territory is estimated.

Peculiarities of the diurnal dynamics of the aerosol optical depth of the atmosphere in the infrared wavelength range

An attempt of the physical interpretation of the formation of the diurnal behavior of the atmospheric aerosol optical depth in the infrared wavelength range is undertaken based on the data of a comprehensive experiment that includes spectral measurements of the atmospheric transparency in near-ground and inclined paths in the wavelength range Δλ = 0.44–1.06 µm and measurements of the turbulent heat flux. Two hypotheses are proposed for the explanation of the effect of the postmeridian decrease of the atmospheric aerosol optical depth.

Simultaneous measurements of structure characteristics of atmospheric refraction by optical and acoustic methods

Comparative measurements of the turbulence level were carried out in the surface layer by optical and acoustic methods with the use of equipment designed at Zuev Institute of Atmospheric Optics. The turbulence level in the surface layer was studied at a height of 1.65 m. A stable difference between optical and acoustic data has been found.

Relation of anomalous atmospheric conditions to electric field variation

Aerosol influence on strength value of atmospheric electric field in near-ground layer, based on in-situ measurements data, has been analyzed. The peculiarities of electrooptical relations in haze and smoke haze, cased by forest fires in summer, and through aerosol accumulation in near-ground layer at temperature inversion occurrence in winter, have been studied. The reasons of the revealed differences in the influence of smoke haze of various origin on atmospheric electric field value have been discussed.

Experimental estimates of turbulence anisotropy tensor components in the surface air layer

Based on experimental data obtained in the surface air layer with different structures of the underlying surface, components of the turbulence anisotropy tensor are calculated and their average values and root-mean-square deviations are determined for different conditions of measurements. The influence of experimental data processing modes on the statistic of anisotropy tensor components is considered. A high degree of stability of average values of tensor components in different conditions is reported.

Experimental estimates of the structure parameter of the refractive index for optical waves in the surface air layer

The structure parameter of the refractive index of optical waves Cn2 in the surface air layer is analyzed in the context of results calculated from the structure parameter of the air temperature Cn2. The estimates for Cn2 based on an optical differential turbulence meter and ultrasonic anemometer-thermometers are compared. The systematic difference between these estimates at a high degree of correlation is noted. The diurnal mean profile of Cn2 in different seasons in territories with a natural landscape and urban territory is obtained and analyzed.

Joint measurements of atmospheric turbulence level with optical and acoustic meters

Complex measurements of atmospheric turbulence level were carried out with the use of a differential turbulence meter, a wavefront sensor, and ultrasonic weather stations. The refractive index structure constant was measured daily along horizontal optical paths at the Basic Experimental Station of the V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences. The comparative analysis of the data received is given.

Study of the atmospheric boundary layer parameters under urban conditions with local and remote diagnostics facilities. Part. 2. Air temperature and heat flux

We considered the results of the complex measurements of meteorological parameters at two observation sites in Moscow with the help of Volna-4 sodar, the Meteo-2 ultrasonic meteorological station, and the MTP-5 meteorological temperature profiler. The frequency of occurrence and the heights of temperature inversion boundaries under the conditions of woodland-park zone are analyzed. The obtained results are compared with analogous estimates of some other authors for the central part of the city. It is found that a stable stratification of the urban roughness sublayer takes place considerably more often in the woodland-park zone of the city than in the central part of the urbanized territory.

Study of parameters of the atmospheric boundary layer under urban conditions by means of local and remote diagnostics. Part 1. Interlevel wind speed correlations

The results of complex measurements of meteorological parameters at two observation sites in Moscow with a Volna-4 sodar, Meteo-2 ultrasonic meteorological station, and MTP-5 meteorological temperature profiler are considered. The coefficients of the interlevel wind speed correlation are analyzed after initial data averaging over 10-min time intervals. A minimum of correlation is identified, which corresponds to the height of the urban roughness sublayer. The possibility of determining the height of the atmospheric surface layer over urbanized territory from estimates of the coefficients of correlation is discussed. It is noted that an increase in the wind speed results in a growth of the interlevel correlation inside the urban roughness sublayer and above the atmospheric surface layer; however, the correlation changes insignificantly in the inertial sublayer.