Aerul şi Apa: Componente ale Mediului (Mar 2011)
CHARACTERISTICS OF HEAVY RAINFALL PARAMETERS IN THE NORTH-WESTERN ROMANIA
Abstract
Characteristics of heavy rainfall parameters in the northwesternRomania. The paper analyzes the frequency, duration, intensity andquantity of heavy rains in north-western Romania, based on data from 14meteorological stations in that area, located in different terrain conditions, using1975-2009 period. Identification of the torrential rains was made on Hellmann’scriteria. In the review period were identified 271 torrential rainfall events,representing only 0.89% of all precipitation cases with significant intensity ingenerating liquid surface flow. During the year, the highest frequency ofoccurrence is from June to August (between 61.5 and 90% of cases), with a slightpredominance of June. In terms of duration, the highest shares of torrential rainshave 3-6 hours (37.3%), followed by those of 1 to 2 hours (25.1%), this structurerevealing different genetic conditions. Diurnal variation shows maximumoccurrence of heavy rains in the afternoon and evening (between 13 and 20Romanian Summer Time - RST), the phenomena starting earlier in mountainousareas (11-12 RST) and later in the lowlands (16-17 RST). Water amounts variesquite large, with values ranging between 1.2 and 82.7 mm, and their averageintensity is between 0.12 and 1.80 mm/min, being noticed a strong correlationbetween average duration and intensity of rainfall, it ultimately reducing the growing period.
