1969/01/01 by L. Koczy, Koczy, L.
Earth and Planetary Sciences · Environmental Science · #Cryospheric studies and observations #Arctic and Antarctic ice dynamics #Polar Research and Ecology
paper · pdf · doi:10.2312/polarforschung.39.1.250
The extinction coefficient of two different types of river was investigated in relation to its dependence on the wave length of the transmitted light. Zusammenfassung: Einige Messungen des Extinktionskoeffizienten von Fluseis. Der Extinkttonskoetuztent wurde fur zwei verschiedene Eissorten in seiner Abhangigkeit von der Wel1enlange der durchtretenden Strahlung untersucht. In the spring of 1967, some measurements of the extinction coefficient were made using samples of the river of Goldstream Creek, near Fairbanks, Alaska. A Linke Feussner actinometer in conjunction with a galvanometer, both constructcd by Kipp and Zonen, Holland, were used for this purpose. The measurements were carried out with direct solar radiation in a mean temperature of 6 C, as well as in a cold room with an artificial light source (20° C). Two very different types of were used, normal river which is formed when the stream freezes over in the fall, and overflow ice, viz., which occurs when the stream is solidly frozen, fresh ground water is forced to the surface, and the resultant mixture of snow and water freezes. The overflow ice has a higher air content than the normal river and consequently, a brighter appearance (Fig. 1), These overflows are frequently found in Alaskan streams and occur several times during one winter, as can be inferred from the stratified structure of the ice. By spring time these overflows can build up to a thickness of several meters (Benson and Kreirner, 1969. Kreitner, 1969). With a motor saw, large blocks of were cut out of the stream, The overflow ice is situated near the surface, while the river was found in greater depth. With different hand saws plates of were cut with a thickness between 0.2 and 6.0 cm. * Dr. Gerd Werrdler, Geophysical Institute, University of Alaska, College, Alaska 99701