Synoptic Conditions for the Novorossiysk Bora Formation in Modern Climate

The authors have developed a classification of the conditions for the Novorossiysk bora formation based on the data on the synoptic conditions preceding the phenomenon and contributing to its development. The Azores, North Atlantic, Siberian, and Arctic classes of the Novorossiysk bora have been identified. The authors also has developed a synoptic and climatic method for classifying the cases of the Novorossiysk bora, which consists in transition from analyzing typical schemes of synoptic processes to analyzing directly the fields of surface pressure and geopotential height that characterize each synoptic class of the Novorossiysk bora. The use of this method made it possible to use the data of modeling pressure fields, which are simulated by models much better than wind fields, for the forecast of the phenomenon. Due to this method, it became possible not only to detect cases of the Novorossiysk bora, but also to identify their classes for a long period from 1979 to the present and also to make a forecast of the frequency of the Novorossiysk bora in the 21st century. It has been found that the number of the bora events of the Siberian class, against which the bora of the frontal and monsoon types belonging to the most extreme ones in terms of their meteorological characteristics and consequences is more often observed, will increase in the periods of climate warming.