Turbulence spectra and turbulence scales were measured with the AMK-03 acoustic meteorological station and DJI Phantom 4 Pro unmanned aerial vehicle (UAV). The measurements were carried out in the Geophysical Observatory of the Institute of Monitoring of Climatic and Ecological Systems SB RAS, which is located at a territory with complex orography. The turbulence spectra obtained with the AMK-03 and DJI Phantom 4 Pro generally coincide with some discrepancies observed in the high-frequency spectral range starting from Hz. The lateral and longitudinal turbulence spectra in the inertial range obey the “5/3” law, and their ratio corresponds to the Kolmogorov—Obukhov isotropic turbulence. The obtained experimental spectra were approximated by the least square fit method with the von Karman mathematical model. The turbulence scales calculated from the AMK-03 and DJI Phantom 4 Pro findings coincide, and the condition describing the relation between the longitudinal and lateral scales in the isotropic atmosphere is fulfilled.
The paper shows the possibility of using small UAVs with a rotary wing to monitor the state of atmospheric turbulence at different altitudes. The measurements were carried out at the Basic Experimental Observatory (BEC) of the V.E. Zuev Institute of Atmospheric Optics SB RAS. The turbulence spectra at 4, 10, and 27 m, as well as turbulence scale profiles obtained with three DJI Mavic Mini and one DJI Mavic Air quadcopters are reported. The turbulence spectra measured at different altitudes and turbulence scale profiles are compared with the data obtained from three AMK-03 automated meteorological systems installed at the 4-m and 30-m meteorological towers. It has been found that the turbulence spectra obtained with the AMK-03 and quadcopters are generally in a good agreement with some differences observed in the high-frequency spectral region nearby Hz. During the experiment, Kolmogorov turbulence was observed in the atmosphere in a wide frequency range at all altitudes. This type of turbulence was confirmed by both the AMK-03 and quadcopter data. When determining the longitudinal and lateral turbulence scales at altitudes of 4, 10, and 27 m, the least square fit method was used with the von Karman model as the regression curve. The turbulence scales calculated from AMK-03 and quadcopter data are shown to agree well. The condition describing the relation between the longitudinal and lateral scales in an isotropic atmosphere is true to sufficient accuracy.
The results of studies of the consistent variability of the parameters of the electrode layer of the atmosphere during the passage of thick convective clouds accompanied by rainfall are presented. For a series of cumulonimbus cloud passes with heavy showers high-frequency (periods of less than 10 min) fluctuations in the structure of precipitation in time and size spectrum were analyzed. A correspondence between the variations of hydrometeors flow, electric field potential gradient (∇φ) and polar conductivities (λ±) has been established.
This work is aimed to study of the ν1 band of the methane Raman spectrum in the pressure range of 1–80 atm. The wavenumber calibration was performed using the rotational–vibrational structure of the ν3 methane band. It was established, that pressure shift coefficient is about –0.02 cm–1 /atm, pressure broadening coefficient is about 0.005 cm– 1 /atm. According to the obtained experimental data, in the region of 2914–2916 cm–1 , with an increase in pressure, either the van der Waals methane complexes begin to make a noticeable contribution to the intensity of the ν1 band, or collision–induced Raman scattering increases in this range.
The description of the developed automatic weather station for the Arctic region is presented. The station provides information to the remote user measured data such as three-component vector of wind velocity, air temperature and humidity, atmospheric pressure, precipitation parameters, solar radiation intensity, snow cover depth, and soil temperature profile (including ground surface temperature). The solution to this problem is possible only through the use of automated systems that can data acquisition, process and transmit meteorological information to a remote user in an automatic mode without human intervention.
Traditional and modern devices for measuring snow characteristics are considered. Data from measurements of snow precipitation parameters were obtained and analyzed. The features of measuring the characteristics of snow precipitation accompanied by wind are considered. The main ideas for the development of a new snowdrift meter that meets the modern requirements are outlined.
The turbulent power spectra of Euler angles are studied. The results of their comparison with the spectra of turbulent fluctuations of wind velocity components in the atmosphere are present. Equations are derived for estimating the horizontal wind components as a function of the means and fluctuation components of Euler angles. Time series of turbulent fluctuations in pitch, roll, and yaw angles, as well as time series of turbulent fluctuations of wind velocity components are obtained during an experiment, which was carried out at Geophysical Observatory of IMCES SB RAS in Tomsk Akademgorodok (Russia). The time series of Euler angles and wind speeds were recorded with a frequency of 10 Hz. The automated weather station data witness anisotropy of turbulent flow speed fluctuations during the measurements in the atmosphere: the spectra of fluctuations of the horizontal components coincide, but differ from the spectrum of vertical fluctuations. The fluctuations of the Euler angles show similar behavior: the spectra of fluctuations of pitch and roll angles coincide, but differ from the spectrum of fluctuations of the yaw angle. The spectra of fluctuations of pitch and roll angles and the spectra of fluctuations of the horizontal wind velocity components generally coincide, though differences are observed in the high-frequency region of the spectrum. In contrast to fluctuations of pitch and roll angles, the spectrum of fluctuations of the yaw angle coincides with the spectrum of the vertical wind velocity component in the high-frequency region.
The problem of ideal hover of an unmanned aerial vehicle in a turbulent atmosphere is considered, and the equations for estimation of turbulent fluctuations of the longitudinal and transverse components of horizontal winds are derived independently of the unmanned aerial vehicle orientation and wind direction. Experiments were carried out on the territory of the Geophysical observatory of Institute of Monitoring of Climatic and Ecological Systems, Siberian Branch, Russian Academy of Sciences. It is situated in Tomsk Akademgorodok, on the territory with complex orography, in a parkland zone with buildings of research institutes and motorways. A DJI Phantom 4 Pro unmanned aerial vehicle flew up to an altitude of 30.7 m and approached an automated weather station, mounted at a mast near the Observatory. Time series of turbulent fluctuations of the longitudinal and transverse components of the horizontal wind were received with the use of the automated weather station, and time series of turbulent fluctuations of estimates of these components, from data of unmanned aerial vehicle in the hovering mode. According to the automated weather station, anisotropic fluctuations of the turbulent flow velocity were observed during the atmospheric measurements: the spectra of fluctuations of the horizontal components coincide, but differ from the spectrum of vertical fluctuations. The spectra of fluctuations of the longitudinal and transverse components of the horizontal wind velocity were comparatively analyzed. The general coincidence of these spectra with the spectra of fluctuations of estimates of the components is shown, with, however, significant differences in the high-frequency spectral region.
The description of scheme and control algorithms of the heating system, designed to ensure the optical precipitation gauge operation in extreme weather conditions of the Arctic, are presented. The solution is based on the temperature monitoring of optical windows, electronic components, and protective housings of the device.
The paper discusses the conditions of the “Squall” natural hazard emergence, registered in the end of October 2018 in Tomsk. Meteorological values dynamic specifics are described before and during that phenomenon, based on IMCES measurement-computational system data.
The results of measuring the vertical profiles of the main meteorological quantities in the atmospheric boundary layer to an altitude of 1000 m by the ultrasonic weather station AMK-03, placed on the suspension of a tethered balloon during its ascent and descent are presented in the article. Recommendations on the procedure for performing measurements using an ultrasonic weather station based on a tethered balloon are suggested.
Filtering algorithms for measurement data of the optical rain gauge OPTIOS are presented. Criteria for reducing measurement errors are considered. These errors are associated with registration of objects that are not precipitation particles, and droplets that are broken on elements of the device construction. The examples of the efficiency of proposed filtration methods for precipitation amount measurements are shown.
The paper suggests an approach for cumulonimbus clouds detection, including embedded convection, based on threshold values of surface atmospheric electric field potential gradient. On the example of IMCES SB RAS (Tomsk) measuringcomputation system, authors demonstrate the effectiveness of such approach implementation for real-time information obtaining on submerged convection in frontal cloud fields.
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 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.
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.
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.
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.
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.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.