Investigation of spatial and temporal variability of hydrological drought in Slovenia using the Standardised Streamflow Index (SSI)

Zalokar, Lenka (author), Kobold, Mira (author), Šraj, Mojca (author)

Drought is a complex phenomenon with high spatial and temporal variability. Water scarcity has become a growing problem in Slovenia in recent decades. Therefore, the spatial and temporal variability of hydrological drought was investigated in this study by analysing the Standardized Streamflow Index (SSI). Monthly discharge data series from 46 gauging stations for the period 1961–2016 were used to calculate SSI values at five different time scales (1, 3, 6, 12, and 24 months). The results indicate that the frequency and intensity of droughts in Slovenia has increased in recent decades at most of the analysed gauging stations and at all time scales considered. Spring and summer periods were identified as critical in terms of water deficit. SSI values vary independently from the location of the gauging station, confirming that drought is a regional phenomenon, even in a small country such as Slovenia. However, SSI values vary considerably depending on the time scale chosen. This was also confirmed by the results of the hierarchical clustering of the number of extreme droughts, as various time scales resulted in a different distribution of gauging stations by individual groups.

• Language: English
• Keywords: hydrological drought, Standardised Streamflow Index, SSI, hierarchical clustering, seasonality
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 15 str.
• Numbering: Vol. 13, iss. 22, art. 3197
• PID: 20.500.12556/RUL-133437
• UDC: 556
• ISSN on article: 2073-4441
• DOI: 10.3390/w13223197
• COBISS.SI-ID: 85603331
• Publication date in RUL: 26.11.2021

Record is a part of a journal

• Title: Water
• Shortened title: Water
• Publisher: Molecular Diversity Preservation International - MDPI
• ISSN: 2073-4441
• COBISS.SI-ID: 36731653

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 11.11.2021

Secondary language

• Language: Slovenian
• Keywords: hidrološka suša, standardizirani indeks pretoka, SSI, hierarhično razvrščanje, sezonskost

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0180
• Name: Vodarstvo in geotehnika: orodja in metode za analize in simulacije procesov ter razvoj tehnologij

• Funder: Other - Other funder or multiple funders
• Funding programme: UNESCO, IHP, Slovenian National Committee
• Project number: C3330-20-456010