CLIMATE CHANGE IMPACT ON STREAMFLOWS IN BOSNIA AND HERZEGOVINA: A CASE STUDY OF THE LOWER BOSNA RIVER BASIN

Abstract. The paper analyses the impact of climate change on streamflows in the Lower Bosna River Basin in the period 1961–2020. Data on mean monthly air temperatures and precipitation were analyzed for 5 meteorological stations across the basin, whereas streamflows were analyzed for the Doboj hydrological station. The nonparametric Mann-Kendall test and the Sen’s method were used to calculate the trend magnitude and its statistical significance. A significant warming tendency was present throughout the year across the entire basin, whereas the most striking warming was observed in the summer. Mean annual temperature increased significantly, whereas trends in mean annual precipitation were also positive, but mostly insignificant. Consequently, annual streamflows displayed a significant downward trend. Negative discharge tendencies were detected in all seasons but were most prominent in winter and spring. Significant air warming, combined with the downward discharge trends throughout the year will lead to decreased water availability in the future. Key words: air temperature, Precipitation, streamflows, Climate change, Trend analysis.