Uneven trends of temperature indices during the growing season and dormancy in Serbia

Abstract

This paper documents the change of temperature indices for the growing season (April–September) and dormancy (October–March) in Serbia based on observations from 26 meteorological stations. The mean, maximum, and minimum daily temperatures, as well as eight extreme temperature indices, were examined. A trend analysis revealed uneven changes in the growing season and dormant temperatures during the observation period divided into two parts (1961–1980 and 1981–2010) according to the results of the sequential Mann–Kendall test for detecting change points in time series. The dormant temperature changes were quite uniform during the entire examined period, while the growing season temperature displayed a complex pattern of change. In the sub-period 1961–1980, all examined temperature indices exhibited a cooling tendency during the growing season and a warming tendency during dormancy. A larger decreasing trend was detected in the growing season maximum temperature (a nationally averaged rate − 1.10 °C per decade) and related indices than in the growing season minimum temperature (a nationally averaged rate − 0.37 °C per decade) and related indices. In the same sub-period, the dormant maximum and minimum temperatures increased at the same rate of 0.49 °C per decade on average for all stations. During the sub-period 1981–2010, a warming tendency was detected both in the growing season and dormant temperature indices with similar magnitudes of the change (minimum and maximum temperatures increased on average from 0.48 to 0.56 °C per decade). Examination of the relationship between the temperature indices and large-scale circulation patterns revealed that only the East Atlantic pattern displayed significant association with trends of examined indices, but only during the growing season in the sub-period 1981–2010.