Variations in the electrical characteristics of the surface layer of the atmosphere during the passage of cumulonimbus clouds (Cb) and the accompanying atmospheric phenomena (snow showers, drifting/blowing snow) in the cold season have been investigated. The statistical characteristics of electric field potential gradient values during the passage of winter Cb are estimated. Comparison of the potential gradient values during the passage of Cb in the warm and cold seasons are compared.
The analysis and the quantitative assessments have been made for consistent variations in potential gradient, polar electrical conductivity, parameters of falling hydrometeors, the spectrum and the aerosol concentration in adverse weather conditions during such events as heavy precipitation, squall, mist/ fog.
The specifics of snow precipitations characteristics measurements are considered. The paper presents the description of the method based on obtaining and analyzing precipitation particle shadow images for measurements of snow precipitations. There are results of snowfall characteristics measurements that have been registered 9 November 2015.
Conception of design of measuring and computing system for monitoring atmospheric boundary layer is proposed. The system includes: stationary measuring complex consisting of four multiple-elevation ultrasonic weather stations and mobile measuring complex consisting of transportable weather station, touch probing system of weather data profile based on unmanned aerial vehicle and also Raman scattering gas analyzer, and new modification mercury gas analyzer.
There are specifics of use of the obtaining and analyzing precipitation particle shadow images method for the hail precipitation investigations. Descriptions of the method and operation of the new optical rain gauge measuring system are presented. There are estimations of the device capabilities and prospects of its use for measurement of hail characteristics.
The variations of the surface potential gradient, and positive and negative air electric conductivities during the passage of the series of atmospheric fronts, which were accompanied by the showers and continuous rains, are investigated. According to the analysis of experimental data, the distortion of the related variations of the potential gradient and air electric conductivities occurred during rain. The value of this distortion depends on the rain type and the rain rate.
A simple and effective calibration technique for the new optoelectronic dual channel precipitation gauge (ODPG) is developed. The main result of the calibration procedure is minimization of the particle size measurement errors that depend on the optical system aberrations. Laboratory tests are carried out for generation of the calibration parameters, and for confirmation of the first theoretical evaluations performed for the device technical characteristics. The ODPG field tests (measurement of the rain parameters) demonstrate high degree of reliability of the developed design – steady operation of optical and electronic systems after transportation, efficiency of algorithms used for acquisition and processing of measurement data and calculation of the precipitation parameters.