The interannual and decadal variability and trends of winter (December to February) air temperature over the Oltenia Plain area is analysed for the period 1961 to 2010. The datasets cover monthly temperatures from six meteorological stations. The variability of the temperature data was analysed by means of standard deviation, the mean of three distinct sub-periods (1961-1990, 1971-2000, 1981-2010), as well as the mean of ten-year intervals. Linear regression and the non-parametric Mann-Kendall test were used to emphasize any trends present in the datasets. From the temporal variations viewpoint, an increase in temperature is observed particularly in the third and fourth decades, as the average values for the last decade mark a slight decrease in temperature. From the spatial distribution viewpoint, the most significant positive deviations characterize the northern and western part of the plain. Mann-Kendall test illustrates a monotonic upward trend all over the analysed region, but the results are not statistically significant except for the aforementioned parts of the plain for the entire winter season and February.
Winter air temperature characteristics within Oltenia plain