Spatial distribution of some dynamic parameters during the evolution of selected depressions over the area of Cyprus

During the cold season, the cyclonic systems that reach the eastern Mediterranean from the surrounding geographical region and those that are formed over the area are largely associated with unsettled weather conditions over the island of Cyprus. For a better understanding of the evolution of these synoptic-scale systems, some of the dynamic characteristics of selected groups of baroclinic depressions that affected the area during the winter season were studied. More specifically, the spatial isobaric distribution of the fields of relative vorticity, divergence, vertical motion and a static stability parameter were considered in relation to the evolution of each grouping of such depressions. The study focuses on 150 depressions in the colder months of November to March, from the beginning of January 1988 till the end of December 1996. Five groups of depressions were established and studied separately: those originating from north, east, south and west and those that form in situ. The time of maximum deepening of each depression was determined from the surface synoptic analyses and the spatial distributions of the above parameters were established for this time, 1 day before and 1 day after. The data used are the 2.5° x 2.5° standard-level isobaric analyses compiled by the National Centers for Environmental Prediction-National Center for Atmospheric Research. The results presented in this study refer only to three tropospheric isobaric levels, namely 850, 500 and 300 hPa.