Snow Shielding
In ACE a mandatory sample attribute is the shielding factor, which is the product of the snow shielding and topographic shielding factors. This utility is designed to find the effect of changes in mean annual snow depth on the snow shielding factor. Mean annual snow depth is used as it requires fewer inputs than winter snow depth, so should be used only in exploring the effects of a permanent, year round snow/ice/soil cover:
The first input is ‘Mean Annual Snow Depth’ in cm. Values of 160 g cm-2 for snow attenuation and 0.2 g cm-3 for snow density are supplied by default. For reconstructions where monthly snow depths and densities are known, the Monthly Snow Shielding utility can be used, which has the same variables as the Annual Snow Shielding Utility but sums contributions on a monthly basis:
Click on image to Expand
Figure 17 from Gosse and Phillips 2001 shows actual age differences (1-snow shielding factor )*100 for different snow densities and depths.
To see a demonstration of this utility click here (requires Quicktime)