Item: On the Topographical Origin of Some Remaining Snow Patterns,
Title: On the Topographical Origin of Some Remaining Snow Patterns,
Proceedings: Proceedings of the 1996 International Snow Science Workshop, Banff, Canada
- Yutaka Yamada [ Institute of Snow and Ice Studies, NIEO, 940 Japan ]
Abstract: Yukigatas are complex patterns on mountainsides formed by combinations of bright domains covered with remaining snow and dark domains of ground or trees. A positive type (bright) yukigata shows its pattern on the hillside as remaining snow and a negative type (dark) yukigata shows its pattern as ground or trees. The formation mechanism of yukigatas is closely related to snowpack, snowmelt and topography. In this paper, I analyze two representative yukigatas, one positive and one negative, with aerial photographs and a Digital Elevation Model (DEM). Then, I examine the relation between the origin of yukigatas and topography. The positive type yukigata called "Nichirin" (the sun) forms on landslide terrain that has an abrupt change in slope. Avalanche debris piles up below the steep slope in an area that is circular in shape. The negative type yukigata called "Hane-uma" (galloping horse) forms under a cliff on steep slopes of 35 degrees or more. Full-depth avalanches are apt to take place these denuding that slope. Thus, the formation of these two yukigatas is mainly due to topography that causes avalanche release.
Language of Article: English
Keywords: yukigata, snowpack, avalanche, landslide, topography, oem
Digital Abstract Not Available