Diel discharge cycles explained through viscosity fluctuations in riparian inflow

Abstract: Diel (also called diurnal) discharge patterns with minima in the afternoon are generally explained by the daily cycle of evapotranspiration, while maxima in the afternoon are often linked to freeze-thaw cycles. In a schistose and forested headwater catchment in Luxembourg, we observed daily discharge maxima in the afternoon, although temperatures remained persistently above zero and vegetation was still in a dormant state. We show that diel water temperature fluctuations––and therefore viscosity fluctuations––in the upper layer of the riparian zone can be an explanation for the observed daily discharge maxima in the afternoon during the dormant season. In the transition period between the dormant and the growing season, the counteracting viscosity and evapotranspiration processes cancel each other out. Subsequently, during the growing season, evapotranspiration is the dominant process guiding the diel discharge pattern; nevertheless, the viscosity effect might still be present, but invisible. We believe this finding also to be of relevance when analyzing daily fluctuations of biogeochemicals in stream water

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Water resources research. - 52, 11 (2016) , 8744-8755, ISSN: 1944-7973

Classification and Topics

• Classification: Bibliografien

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2024
• Creator: Schwab, Michael ; Klaus, Julian ; Pfister, Laurent ; Weiler, Markus
• Contributor: Albert-Ludwigs-Universität Freiburg. Professur für Hydrologie, 2013-

Further information

• DOI: 10.1002/2016wr018626
• URN: urn:nbn:de:bsz:25-freidok-1425077
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 15.08.2025, 7:31 AM CEST