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Show SECTION k- SNOWPITS A good snow shovel is the one indispensable tool for the snow and avalanche observer. The best all- around model is the style known as a " Coal and Street- Cleaner's Shovel". This has a D-handle and a nearly flat, ribbed blade of square shape. It is available in both steel and aluminum ( A5a). The aluminum model is preferred for back- packing to distant sites and is also highly recommended for avalanche caches. The steel is more durable and better- suited for digging in hard, icy snow. Other shovel types may be used for special purposes. A 1^- inch grain scoop ( preferably aluminum) is useful for deep, soft, new snow, but has too big a " bite" for comfortable shoveling of dense snow. A 12- inch grain scoop or coal scoop ( not to be confused with the square shovel described above) also makes a useful, all- around snow shovel. A deeper dish than the street- cleaner's model makes it more efficient in soft, loose snow. A flat blade, on the other hand, does a much better job of trimming pit walls and cutting snow blocks. Avoid completely those shovels sold as " snow shovels". These are designed for pushing snow off sidewalks; they are totally unsuitable for serious digging. In climates where the snowpack is deep, dense, and hard, a useful auxiliary shovel is one with a slender, pointed blade on a short D- handle ( Drain and post- hole spade, A5b). The blade should be only 5 to 6 inches wide at the shoulder. This is used to dig out density tubes after they have been placed in the pit wall. The type of shovel known on the West Coast as a " clam gun" also serves very well. Density measurements are the backbone of pit studies. A set of density tubes is an essential part of snowpit equipment. The standard type has long been the 500 cc stainless steel tubes developed in Switzerland( A2). If carefully handled, they will give many years of service. Such tubes should be ordered with rubber or plastic caps which retain loose snow. These caps are necessary even if the tubes are carried only a few feet from pit wall to the weighing balance. A set of 10 tubes in a carrying case will meet most needs for snow density measurements. The tubes should be numbered with durable paint and the matching numbers painted on the caps of each tube. Tare weights can then be determined for each tube and its own caps. If the caps are switched from tube to tube, the combined tare weights will vary. If machine shop facilities are available, a considerable cost saving can be achieved by machining such 500 cc tubes out of stock stainless steel tubing ( A2). Tubes made in this fashion according to the given specifications are very close in size to the Swiss standard tube and will accept the rubber caps made for the latter. Fiberglass tubes identical in size to the steel ones are also available from the supplier of the standard 500 cc tubes. These have a distinct advantage of lower weight, but are much less durable. 25 |
