Analysis of regional river flows in Slovenia
- Authors: Sašo Petan, Maja Koprivšek
- Citation: Acta hydrotechnica, vol. 37, no. 66, pp. 65-77, 2024. https://doi.org/10.15292/acta.hydro.2024.04
- Abstract: To comprehensively evaluate regional river flows in Slovenia over the period of 1961–2023, we conducted a detailed analysis encompassing average annual, trimonthly, seasonal, and monthly river discharge data from 87 hydrological stations across 15 regions. These regions are delineated and named according to the prognostic division of Slovenia. By employing the area-weighted standardized stream flow index (RSI), we assessed the regional river flows across various time intervals. Our findings show notable shifts in the interannual distribution of river flows, particularly an increase in anomalous conditions, notably dry ones. The years 1965 and 2014 were highlighted as extremely wet, and 2003 and 2011 as extremely dry. Among the regions, Obala stands out with four extremely dry years that occurred after 2010. We observed a doubling in the occurrence of dry seasons across Slovenia after 1992, with the majority of dry springs extending into dry summers. Furthermore, the average number of dry summers per region quadrupled at least during this period, highlighting Kočevska, Notranjska, Savinjska, Spodnjeposavska, and Obala as particularly exposed regions. Additionally, the incidence of drought episodes after 1992 increased by over 50%, with their duration nearly doubling. Consequently, the proportion of time with the presence of drought or wet episodes became dominant.
- Keywords: Regional river flows, standardized streamflow index, indicators, drought and wet episodes, seasonality, Slovenia.
- Full text: a37sp.pdf
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