Search

The results of integrated instrumental observations of thunderstorm activity around Yakutsk at a radius of 400 and 30 km are presented. The seasonal course of thunderstorm activity was found to contain characteristic peaks in the first 10 days of June and the last 10 days of July or early August. The fraction of cloud-to-ground discharges in Central Yakutia is 40-60%, which is consistent with observations in Western Siberia (40-50%). The number of positive discharges to the ground was 8-15% of all cases of discharges to the ground, which is consistent with observations in Germany (17%) and slightly exceeds the observed number in the Caucasus (2.2-8.2%) and United States (4.5%). The thunderstorm activity in Yakutsk is three times higher than in the area around Yakutsk with a radius of 400 km, which can be explained by the fact that the city is a heat island. [ABSTRACT FROM AUTHOR]

Characteristics of thunderstorm cores, obtained from observations in Central and South Yakutia with the help of three one-point thunderstorm detectors with a radius of action of 300 km, located at Yakutsk, Mirnyi, and Neryungri, are presented. As a result of processing performed using two-step cluster analysis, the main parameters of thunderstorm cores have been obtained: number of discharges, area, intensity, transverse and longitudinal dimensions, shape, and lifetime. The distribution over occurrences of areas of cells has an exponentially falling form. It is shown that with increase of the mean area of an individual core S in a thunderstorm, the area occupied by this thunderstorm S grows exponentially, but with increase of the area of cores the density of discharges in them falls, and this dependence can be written in exponential form. The percent distribution of thunderstorms over density of discharges can be described by a falling power-law function. [ABSTRACT FROM AUTHOR]

Considered are the methods of thunderstorm cells clustering using the data of one-point and multipoint lightning detectors and their characteristic features based on the observations in Yakutia. As the thunderstorm activity intensifies, i.e., the lightning discharge density in the region increases, the number of storm centers and the number of cells in the center grow up. The sizes and the lifetime of thunderstorm cells in Yakutia correspond to the similar data for North America and the European part of Russia. The maximum area and intensity of both center and thunderstorm cell are observed at the stage of development, in the middle of their lifetime. As the cell area increases, the intensity of lightning discharges decreases inversely to the area. It is revealed that as the cell oblongness increases, the intensity of lightning discharges in these cells becomes higher as well. [ABSTRACT FROM AUTHOR]