Analysis of extreme precipitation indices in the east herzegovina (Bosnia and Herzegovina)

Abstract

The changes in annual and seasonal extreme precipitation indices over the East Herzegovina region (Bosnia and Herzegovina) were examined. The data on daily precipitation during the period 1961–2016 from 13 meteorological stations were used for the calculation of 12 extreme precipitation indices recommended by the Expert Team on Climate Change Detection and Indices for the climate change assessment. The results show a downward trend in the precipitation on wet days (PRCPTOT) and in the frequency of days with precipitation (R0.1mm, R1mm, R10mm, and R20mm), whereas the duration of dry spells increases (CDD) over the entire East Herzegovina region. The trends that indicate increasing dryness are particularly pronounced and significant in the summer season. Although the total precipitation decreases, the upward trends in heavy precipitation events such as RX1day, RX5day, SDII, and R95p indicate changes towards more intense precipitation (particularly pronounced since the beginning of the 21st century). Precipitation variability was strongly dictated by the large-scale atmospheric circulations—the North Atlantic Oscillation, the East Atlantic/West Russia pattern and the Arctic Oscillation, especially during the winter season—the significant negative correlation was determined for the majority of extreme precipitation indices.