Errors in Ablation Measurements from Settlement and Sub-Surface Melting

Abstract

AbstractBoth long and short-term snow ablation measurements usually contain errors when made with a simple ablation stake. Ablations measured over long periods for glacier regimen studies are subject to a settlement error in even dense snow, corrections for which may be made by simultaneous measurements with stakes of different lengths. For observation periods in the order of twenty-four hours or less, both mass loss and ice melt are often poorly represented by the simple product of mean bulk density and change in surface level. These quantities may be measured directly by successive determinations of bulk density and ice density profiles in the surface snow layer. Under certain favorable conditions, they may also be derived by observing directly the total and ice mass changes in a sampled area of the snow surface.