National-scale water balance in Slovenia (1972–2024): Long-term trends and variability in water balance components

Peter Frantar; Frank Herrmann; Mišo Andjelov

doi:10.3986/AGS.14632

Authors

Peter Frantar Slovenian Environment Agency, Ljubljana, Slovenia; Faculty of Environmental Protection, Velenje, Slovenia https://orcid.org/0000-0003-0501-4930
Frank Herrmann Forschungszentrum Jülich, Agrosphere Institute (IBG-3), Jülich, Germany https://orcid.org/0000-0003-4939-0479
Mišo Andjelov Slovenian Environment Agency, Ljubljana, Slovenia https://orcid.org/0009-0009-4383-7939

DOI:

https://doi.org/10.3986/AGS.14632

Keywords:

hydrology, water balance modelling, mGROWA, climate change, hydro-climatological trend indicator, water resources management, Slovenia

Abstract

Climate change is altering hydrological processes and water availability, requiring robust long-term analyses based on consistent data and models. In the article, the main components of the hydrological water balance––precipitation, evapotranspiration, and runoff––in Slovenia for the period 1972–2024 are analysed. The analysis is based on results from a verified national-scale mGROWA water balance model. The objective of study is to identify trends that could be relevant for water resources management in a changing climate. A key finding is that evapotranspiration has increased significantly in large parts of the country. However, above-average precipitation in recent years has so far compensated for this increase, preventing a country-wide decline in average runoff. Finally, a hydro-climatological trend indicator is proposed as a future element for monitoring the water balance components in Slovenia.

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