Peculiarities of the thermodynamic state of the atmosphere under heavy precipitation in the Perm region / Sivkov B.A., Kalinin N.A. // Hydrometeorological Research and Forecasting, 2020, no. 1 (375), pp. 83-95.

The paper considers the indices of atmospheric instability and their values, which characterize the thermodynamic state of the atmosphere during heavy precipitation (≥ 50 mm/12 hours or ≥ 30 mm/1 hour) depending on the synoptic conditions, the precipitation type, and its duration. The study is performed for the territory of the Perm region based on data for 1979–2018. The indices based on the particle method (CAPE, LI, and CIN), temperature and humidity characteristics of the atmosphere (K, TQ, Fateev index), as well as the indices taking into account both these factors (DCI and TI) are chosen for the study. The analysis revealed that heavy precipitation is most often associated with the movement of occlusion fronts and cold fronts. The higher values of indices predominate on the cold fronts. The discrimination of precipitation depending on the physical formation conditions showed that shower-type precipitation corresponds to the higher values of CAPE, LI, and CIN indices, while the K, TQ, Fateev, DCI, and TI indices have similar values for both shower-type and widespread precipitation.

Keywords: heavy precipitation, instability indices, CFS reanalysis, Perm region

DOI: https://doi.org/10.37162/2618-9631-2020-1-83-95

Tab. 3. Fig. 3. Ref. 12 .