Trends in air temperature and atmospheric precipitation in Botoşani between 1961 and 2017

Abstract

Air temperature and precipitations are major factors affecting the climate of a certain place. They define the basic matrix of the climate, and their evolution are of interest for the whole of both human and scientific community. The purpose of the present study is to highlight the sign and the magnitude of the trend in the air temperature at Botoşani city weather station for the whole period 1961-2017, and for both its major subdivisions (1961-1990 and 1991-2017, respectively) throughout different temporal subsets (from the level of an average year to the level of a month). Besides air temperature, we determined the evolutive trend in the amount of rainfall using a similar methodology (based mainly on the Mann- Kendall and t tests).
Following our approach, we showcased the thermal and pluviometric reality at Botoşani, which is in a continuous change (as for the temperature values) or in a relatively dynamic balance (with respect to the amount of precipitations). More precisely, at Botoşani, against an annual average temperature of 9.4°C and an annual average of precipitations of 569.0 mm, after the year 1961 and mostly after 1990, the tendency was positive, which indicates an increase in air temperature. From a thermal point of view, considered annualy, seasonally and by warm and cold seasons (excepting autumn, with an insignificant increase), air temperature displayed a representative increase in value over the assessed period (1961-2017). On the whole, the annual temperature values increased by 0.32°C / decade, which presents a maximum statistical significance. Annual amount of rainfall increased over the period 1961 – 2017 by 4.46--5.35 mm/ decade, but this was not statistically significant.