Author(s): Einar Tesaker

Linked Author(s): Einar Tesaker

Keywords: No Keywords

Abstract: A distinct change between gentle and steep rivers may be set at a flow velocity near 0.6 m/s. At this limiting velocity, which will vary somewhat with depth and temperature, an ice cover will not grow against the current Ice formation in steeper rivers will instead be ruled by various dynamic phenomena and be strongly dependent on the river topography and the local flow conditions. A special phenomenon in ice covered sloping rivers is the venting holes, balancing the heat production from reduction of potential head with the various heat losses. Factors affecting this balance are e. g. ice thickness, snow cover, variation of flow etc, in addition to meteorological conditions and river slope. When this balance has been obtained, the ice formation process is halted, until changes of the external factors cause restart of the process. Such changes are e. g. increasing discharge, causing local flOoding or breakup, or heavy snowfall causing collapse of bridging ice.

DOI:

Year: 1994