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The paper examines changes in air temperature, precipitation, and river discharges on seasonal and annual scale over the Sava River watershed in Bosnia & Herzegovina during the period 1961-2016. Based upon data gathered from 11 meteorological stations and 3 hydrological stations, hydroclimatic variables trends were established by utilizing the nonparametric Mann-Kendall test and the nonparametric Sen's slope estimator. The results show significant positive seasonal and annual trends (expect for autumn, during which upward trends were insignificant) in air temperature, whereas both positive and negative insignificant seasonal and annual precipitation trends are shown where determined for the entire watershed. Most prominent upward trends in air temperature were found in summer and afterwards in winter and spring, indicating a pronounced warming tendency over the Sava River watershed. Trends in river discharge displayed a negative tendency in all seasons. Nevertheless, a majority of estimated trends of river discharges were weak and statistically insignificant. Throughout the year, river discharges showed significant positive correlation with precipitation, whilst connection with air temperature was mostly significant and negative. The study results suggest that climate is an important factor affecting river regimes, as well as that changes in river discharges are reflecting recent abrupt changes in climatic variables. [ABSTRACT FROM AUTHOR]

The paper analyses, spatial and temporal patterns of precipitation over Montenegro. Data on mean monthly precipitation during the period 1961-2015 from 17 meteorological stations were used for the analysis. Four regions with different spatial precipitation regimes were identified by using the principal component analysis and the agglomerative hierarchical clustering method. A downward tendency in annual precipitation prevails over Montenegro. The most prominent reduction was present in the summer season. In contrast, precipitation increased during autumn. However, the majority of estimated trend values was low and statistically insignificant. [ABSTRACT FROM AUTHOR]

The paper investigates the spatial distribution of the seasonal and annual precipitation in Bosnia and Herzegovina. The mean monthly precipitation data from 40 meteorological stations covering the standard climatological thirty-year period (1961-1990) were used for the analysis. Seven precipitation-based parameters were used to regionalize climate in Bosnia and Herzegovina by using the Principal Component Analysis and clustering techniques. The spatial patterns of precipitation were determined by using the R-mode principal component analysis with varimax rotation. The first two principal components, which describe 97.60% of the total variance, were taken into consideration. The varimax rotated scores were subjected to the Cluster Analysis in order to identify homogeneous precipitation regions over the territory of Bosnia and Herzegovina. The agglomerative hierarchical clustering identified three sub-regions with different precipitation regimes. The complex orography, i.e., the influence of the Pannonian Basin, the Dinaric Alps, and the Adriatic Sea, is one of the most decisive factors that affect spatial patterns of precipitation in Bosnia and Herzegovina. [ABSTRACT FROM AUTHOR]