Submitted to: Snowmelt Erosion and Related Problems International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: November 15, 2000
Publication Date: February 1, 2001
Citation: Mccool, D.K. 2001. Runoff and erosion from ephemeral frozen soil. Snowmelt Erosion and Related Problems International Symposium. Technical Abstract: The temperature and precipitation regime in the inland northwestern USA presents unique challenges when conducting hydrologic and erosion research. Unlike areas with colder winter temperatures, the soil freezes and thaws and the snow cover increases and decreases intermittently throughout the winter. In southeastern Washington State, the mean daily temperature in December is about -1oC and in January is about -2oC. It is rare for the soil to freeze deeper than 40 cm, and there is generally no time when an entire winter's accumulation of snow melts. However, the soil occasionally freezes before a long period with snow, and snow depths of 60 cm to 75 cm can accumulate. These cold spells are frequently followed by periods of rapid warming with temperatures of 7 to 10oC. When these conditions coincide, rates of runoff can be quite high with severe damage from flooding. Runoff plots operated for 13 years at the Palouse Conservation Field Station near Pullman, Washington provide event data on snow and frost depths, and runoff and soil loss under a range of crop conditions. Results of a 43-year field erosion survey in southeastern Washington place this data in perspective. The presentation will include a discussion of research methodology as well as results of these studies and their use in calibrating the RUSLE and the WEPP models.