Author(s): Lars Bengtsson
Linked Author(s): Lars Bengtsson
Keywords: No Keywords
Abstract: Ice observations were made in the Rane River 1974-1978. Observations of formation of ice, growth of ice, critical velocities, hydrodynamic stability, supercooled water, ice production in rapids and breakup were theoretically analyzed. Depending on the water velocity an ice cover formed after 40-100 negative °C-degree-days. The growth of ice took place at a static growth when the water velocity was below 0.25 m/sec. However, due to hydrodynamic conditions, the growth might stop early in the winter. Hydrodynamic conditions in the field were well described by the equation suggested by Pariset-Hausser. Supercooling down to -0.10oC was observed. The supercooling was found to depend on the water velocity. The production of ice in a 400-meter-long small river rapid was found to be about 15000 m3/year. Observed and calculated discharge at breakup agreed.
Year: 1978