Factors affecting snow accumulation, melt, and runoff on an Arizona watershed.

Abstract

Factors affecting snow accumulation and melt in the ponderosa pine type on a small Arizona watershed were investigated by using multiple regression analysis. Sunlight factor, elevation, canopy coverage, and canopy coverage to the north were the important variables in models predicting snow depth and water content. A regression model was developed to predict loss in snow depth and water content for the watershed. Models having snow depth as the dependent variable consistently explained more of the variation than those having water content as the dependent variable. Snow in low, medium, and high potential solar radiation levels on the watershed was compared using Duncan's New Multiple Range test. The low radiation level accumulated more snow and had a slower melt rate than the other two levels. Eighteen percent of the peak snowpack water content was measured as runoff at the flume of the watershed. There appeared to be about a one-day lag between the time of peak snowmelt and the time of peak runoff.