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Show - 4 - winter snow cover from the Blue Glacier on the Olympic Peninsula of western Washington State. The latter is included as the only representative of the coastal alpine zone presently available. It represents an extreme of maritime climate which is not characteristic of many of the coastal alpine regions. Though these curves have the same general form'- a high rate of initial density increase which gradually declines with time in varying degree- their vertical positions on the graph, that is, the density value reached after a given time interval, are distinctly different. Two reasons may be advanced to explain this difference. One is variation in average values of new snow density ( 24- hour values) among the three areas: Area Mean 24- hr new snow density Berthoud Pass 0.07 g/ cm3 Alta 0.10 g/ cm3 Blue Glacier 0.23 g/ cm3 Presumably the starting point of the densification process must be in part responsible for displacement of the curves. The second reason is the deeper snow cover commonly found in the areas where higher densities are achieved. Typical mid- winter snow depths are: Area Mid- winter snow depth Berthoud Pass 1.5- 2 meters Alta 2.5- 3 meters Blue Glacier 5- 6 meters Compression of the lower snow layers by a larger overburden can thus be responsible for higher densities. In addition, this compression may also |