The Recurrence of Winter Invasions of Cold Air over the Black Sea

V. V. Efimov*, O. I. Komarovskaya

Marine Hydrophysical Institute of RAS, Sevastopol, Russia

* e-mail: vefim38@mail.ru

Abstract

Invasions of cold air masses into the atmosphere over the Black Sea in winter cause the intensive cooling of the surface water layer and contribute to the formation and development of a cold intermediate layer. Although such invasions are relatively rare, they regularly recur in winter. The article studies characteristics of the probability of cold invasions into the atmosphere of the Black Sea region. The article studies series of daily wind data, as well as data on sensible and latent heat fluxes and sea temperature in winter at various points in the west and east of the northern and central parts of the Black Sea. The cases of cold air masses invasion characterized by strong northerly winds were highlighted. The article considered statistical parameters of the winds in points characteristic of the north-westerly, northerly and north-easterly winds in the open central part of the sea and points in the coastal north-western and north-eastern regions. Wind roses and graphs of cumulative distributions were constructed for the offshore points which allowed determining the periods of recurrence of strong northerly winds in winter. A direct dependence of the magnitude of heat fluxes from the sea surface on the northerly wind speed in winter was revealed. It is shown that cold invasion led to seawater cooling as illustrated by the decrease in seawater temperature at the surface and at 50 m depth in 2012.

Keywords

Black Sea, cold invasions, northerly wind, recurrence period, heat fluxes, sea water temperature

Acknowledgments

The study was carried out under state assignment no. FNNN-2024-0014 “Fundamental studies of interaction processes in the sea–air system that form the physical state variability of the marine environment at various spatial and temporal scales”.

For citation

Efimov, V.V. and Komarovskaya, O.I., 2024. The Recurrence of Winter Invasions of Cold Air over the Black Sea. Ecological Safety of Coastal and Shelf Zones of Sea, (3), pp. 6–15.

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