Physical characteristics of seasonal snow cover in northern Alaska

The snow cover of Northern Alaska includes two distinct types which are separated by the Brooks Range. On the North side the snow has a wind-swept, continuous surface; on the south side it lies in heavily forested land with patches of wind blown snow cover occuring on lakes and swamps and on hilltops above timberline. The snow structure on the Arctic Slope consists of a hard, high density, wind-packed layer, overlying a coarse, low-density depth hoar layer. The snow structure in the valleys of Interior Alaska, between the Brooks and Alaska Ranges is characterized by low density, steep temperature gradients, and a thick basal depth hoar layer which sometimes makes up two-thirds or more of the snow pack.