Modeling of the Novorossiysk bora: Part 2. Energetics of the of the atmosphere at the Novorossiysk bora

V. N. Kozhevnikov et al.

Abstract

Important features of the Novorossiysk bora are being investigated using a nonlinear analytical stationary two-dimensional model. Vertical unboundedness of the atmosphere, characteristic features of the shape of the streamlined mountains, the effect of the upper layers on the disturbances in the troposphere are considered. For the first time disturbances are being studied in a wide range of changes in the features of an incident flow. It has been shown that disturbances quite often assume a rotor nature in the leeward zone behind the mountains, and the dependence of disturbances on the wave scale is decreasing only on average, and noticeable deviations from it are oscillatory in nature and depend on the level of reflection of wave energy from the upper layers. Jet stream velocity at the leeward slope estimates energetics of disturbances behind the mountains. It has been shown that its value lies in the range of 18 - 22 m/s under normal conditions. It has been testified that a sharp cooling in event of a bore is determined not by the process of flowing around the mountains, but by the arrival of a colder air mass. It has been concluded that an increase of wind in the surface layer behind the mountains is determined by the height and steepness of the leeward slope of the mountains, the effects of turbulence behind the mountains and is very sensitive to changes in the flow velocity at the leeward slope of the mountains.

KEYWORDS: Atmospheric Physics, Hydrodynamics, modeling, mountain flow, wave frequency, Lyra wave scale, Novorossiysk bora.

Submitted 08.07.2019, accepted 16.10.2019.

 
Citation: Kozhevnikov V. N. et al. (2019), Modeling of the Novorossiysk bora: Part 2. Energetics of the of the atmosphere at the Novorossiysk bora, Russ. J. Earth Sci., 19, doi:10.2205/2019ES000685.
 

Copyright 2019 by the Geophysical Center RAS.