Varrias S., Lolis C.J*, Houssos E.E., Bartzokas A. (2014)
In the proceedings of the 12th International Conference on Meteorology, Climatology and Atmospheric Physics, Heraclion, Crete, Greece, May 2014
Abstract
The main atmospheric circulation characteristics favoring precipitation in Cyclades Islands of southern Aegean, are examined. The data used consist of daily values of: 1) precipitation from the meteorological stations of Naxos, Santorini and Milos and 2) temperature, humidity and circulation parameters with 2.5°x2.5° horizontal resolution over Europe (NCEP/NCAR), for the period 1974-2011. Precipitation values are used for the identification of the sequences of consecutive precipitation days (precipitation events). The grid point data are used for the construction of the daily patterns of the meteorological parameters for the day before the initiation (D-1), the first day (D) and the last day (END) of the events. Factor Analysis and K-means Cluster Analysis are applied to the above parameters for D-1, D and END days and the precipitation events are classified in 7 clusters. Each cluster corresponds to a characteristic evolution (D-1, D, END) type of the above patterns. The tracks of 1) the upper air troughs and the depressions, 2) the vorticity, humidity and instability maxima and 3) the warm/cold fronts or advection areas constitute the main characteristics of the 7 types.