scholarly journals Variations in the radiothermal radiation of the ice cover of Lake Arakhley as a geo-indicator of deformation and cracking

2022 ◽  
Vol 962 (1) ◽  
pp. 012040
Author(s):  
V B Venslavsky ◽  
Yu V Kharin

Abstract In January-March, 2020-2021, radiophysical studies were conducted of radiothermal radiation intensity for the testing site for Lake Arakhley, Transbaikalia, Russia. The set of equipment consisting of four microwave radiometers for the wavelengths from 0.3 to 2 cm was placed on the shore of the lake mounted on a stationary platform. The temperature and deformation of ice were simultaneously measured at the depth of 0.4 meters in two orthogonal directions: west-east and north-south. The temperature was measured with heat gauges in a vertical profile at the depths of 5, 10, 15, 20 and 40 cm. In the process of contact measurements in the period of cracking, signal impulses were recorded in the channel of the deformation sensor placed in the direction of the lake center (west-east). The measurement results were used in monitoring of the condition of the water body. It turned out that in the periods of registering the deformation impulses, changes in the radio brightness temperature and decrease in the ice temperature were observed. The microwave characteristics correlate with the temperature and deformation of the ice cover and may serve as an indicator of the meteorological conditions of the region.

2021 ◽  
Author(s):  
Zoe Davis ◽  
Debora Griffin ◽  
Yue Jia ◽  
Susann Tegtmeier ◽  
Mallory Loria ◽  
...  

<p>A recent method uses satellite measurements to estimate lifetimes and emissions of trace-gases from point sources (Fioletov et al., 2015). Emissions are retrieved by fitting measured vertical column densities (VCDs) of trace-gases to a three-dimensional function of the wind speed and spatial coordinates. In this study, a plume model generated “synthetic” satellite observations of prescribed emissions to examine the accuracy of the retrieved emissions. The Lagrangian transport and dispersion model FLEXPART (v10.0) modelled the plume from a point source over a multi-day simulation period at a resolution much higher than current satellite observations. The study aims to determine how various assumptions in the retrieval method and local meteorological conditions affect the accuracy and precision of emissions. These assumptions include that the use of a vertical mean of the wind profile is representative of the transport of the plume’s vertical column. In the retrieval method, the VCDs’ pixel locations are rotated around the source based on wind direction so that all plumes have a common wind direction. Retrievals using a vertical mean wind for rotation will be compared to retrievals using VCDs determined by rotating each altitude of the vertical profile of trace-gas using the respective wind-direction. The impact of local meteorological factors on the two approaches will be presented, including atmospheric mixing, vertical wind shear, and boundary layer height. The study aims to suggest which altitude(s) of the vertical profile of winds results in the most accurate retrievals given the local meteorological conditions. The study will also examine the impact on retrieval accuracy due to satellite resolution, trace-gas lifetime, plume source altitude, number of overpasses, and random and systematic errors. Sensitivity studies repeated using a second, “line-density”, retrieval method will also be presented (Adams et al., 2019; Goldberg et al., 2019).</p>


1979 ◽  
Vol 84 ◽  
pp. 427-427
Author(s):  
Elly M. Berkhuijsen

The Figure shows the distributions perpendicular to the planes of the galaxies of: (a) the surface density of HI, σHI(R), (b) the surface density of HII regions, σHII(R), and (c) the radio brightness temperature, σTB(R). Details may be found in Berkhuijsen (A.A. 57, 9, 1977; Proc. IAU Symp. 77, 1978); here σHI(R) of the Galaxy was taken from Gordon and Burton (Ap. J. 208, 346, 1976) and σTB(R) of M31 has been revised. Distances to the centre are scaled with the Holmberg radius RH (21, 15 and 7.8 kpc for M31, Galaxy, M33).


Dela ◽  
2019 ◽  
pp. 5-43
Author(s):  
Kristina Glojek ◽  
Asta Gregorič ◽  
Matej Ogrin

The paper presents a study of air pollution caused by black carbon (BC) and fine particulate matter (PM) carried out in the rural area of the municipality of Loški Potok in the winter season of 2017/2018. Measurements of pollutants were performed at two different locations, one at Retje, a village at the bottom of a karst depression, and the other on the top of the Tabor hill in settlement Hrib. The measurement results exposed the main sources of black carbon air pollution in this area: domestic heating with biomass (almost 80% of all black carbon emissions) and unfavorable meteorological conditions for dilution of pollutants during temperature inversions. Three times higher concentrations were measured at Retje during temperature inversions than in the days of mixed atmosphere. In the winter of 2017/18, the average concentrations in the Retje hollow were even higher than those of Ljubljana, which calls attention to the problem of polluted air in rural areas too.


2018 ◽  
Vol 57 ◽  
pp. 02012
Author(s):  
Izabela Sówka

The complexity of describing the very phenomenon of odour nuisance is probably the cause of lack of regulations concerning this topic in the Polish law system as well as standardized odour law in EU. However, in European countries there are solutions regarding this matter. Moreover, methods enabling the evaluation of odour air quality are available. The problem of an authoritative assessment of odour nuisance appears especially when few emission sources characterized by changing conditions and emission profiles and, very often, a complex spatial/topographical structures, also showing locally variable meteorological conditions are located in „vulnerable” places (with many „odour complaints” being recorded there). In conditions similar to the aforementioned the odour situation analysis requires simultaneous usage of several studying methods. In this work are presented: field measurement results and sociological poll results, all carried out for area with several domineering odour emission sources. The research conducted made possible showing the concentration of various odour types and their sources for the researched area, which later on enabled to undertake action aiming at reducing odour nuisance.


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