MANIFESTATIONS OF THE EL NIÑO AND LA NIÑA TYPES IN INTENSE CYCLONES IN THE BLACK SEA–MEDITERRANEAN REGION

Abstract

The extreme phases of the El Niño – Southern oscillation (ENSO) are accompanied by dangerous and destructiveweather events that are difficult to predict. At the same time, El Niño and La Niña events that form it have ambiguous features, andconsidering the classification of these events into different types provides a better understanding of the patterns of their regional manifestations. The aim of the paper is to study the manifestations of classified types of ENSO events in intense cyclonic activity in the Black Sea–Mediterranean region. The analysis was carried out for cyclones identified with the use of the NCEP/NCAR reanalysisdata on the geopotential height of 1000 hPa for the period 1951-2017 and exceeding the 75th percentile in intensity (average depth).It is shown that responses to different ENSO types from September to April differ in sign for the Western Mediterranean, especiallyin winter months, and in intensity (significance) for the Eastern Mediterranean and the Black Sea region. More consistent responsesare observed in the inter-season. In the Western Mediterranean, the frequency of deep cyclones decreases for both types of La Niñain autumn and in January, especially for the central La Niña type. For El Niño types, the frequency of deep cyclones significantlyincreases mainly in spring, especially for the central El Niño type in the Eastern Mediterranean and for the eastern El Niño type in theBlack Sea region. Different responses to El Niño types occur in the Mediterranean region and the Black Sea region due to the shift ofstorm tracks of Scandinavian cyclones to the Black Sea region. The results obtained show the probability of monthly anomalies in thefrequency of deep cyclones of the cold half-year in the Black Sea–Mediterranean region taking into account the type of El Niño/LaNiña events, and contribute to the development of a seasonal regional forecast of weather and climatic anomalies associated withdeep cyclones, with a lead time corresponding to the evolution time of events.