THE IMPACT OF THE PERIODS OF PLUVIOMETRIC EXCESS AND DEFICIT ON THE ENVIRONMENT IN THE PLAIN OF TÂRGOVIŞTE

Mihaela Sencovici

Valahia University of Târgovişte, Romania

Abstract

The study of the periods of pluviometric surplus relied on the calculation and interpretation of the annual, seasonal and monthly values of the Weighted Anomaly Standardized Precipitation index (WASP). This index is calculated according to
the formula: WASP = (Xi – Xmed)/δ, where: xi = term in the series; xmed = average of the series; δ = square average deviation (standard deviation). We considered as cases of pluviometric surplus the situations in which the WASP value went over 1.0. The precipitation data come from a number of two meteorological stations, covering a period of 47 years (1961-2010). In order to discern the importance of the precipitation deficit and the succession of the periods of pluviometric deficit, we calculated the negative deviations of the annual, seasonal and monthly quantities compared to the multiannual average considered normal. We have used the Weighted Anomaly Standardized Precipitation index (WASP) applied to the data coming from 2 meteorological stations (Titu and Târgovişte), for the interval 1963-2010. The frequency of the pluviometric excess years ranges between 26% (Târgovişte) and 22.7% (Titu), values that are lower than those of the years of precipitation deficit (WASP<-0.5). The normal years from a pluviometric perspective (WASP ranging between -0.5 and 0.5) are predominant in the entire plain region, their frequency varying between 44.7% in Târgovişte and 46.8% in Titu. Exceptionally arid and excessively arid years do not exist; the frequency increases from the very arid years (4.3%) to the arid years (10.6%, 12.8%) and then on to the “a little arid” years (14.9-12.8%). The highest frequency of the years that are a little arid (14.9%) has been recorded in Târgovişte. The excess and the deficit
of humidity lead to a series of negative effects on the environment.

Full text .PDF