eC 
f, 
715 June 1972 (N view). 
za : 
“a ro 
— Ose « 
30 June 1972 (S view). 
45 
general conditions for snowmelt on the tundra 
become more favorable toward the end of the 
melting period with increasing air and water 
temperatures, the remaining snow may suddenly 
disappear, allowing a rapid drainage of the melt- 
water. This may contribute to the sharp peaks in 
the hydrograph curves of the rivers that origi- 
nate on the coastal plains (Carlson et al. 1974; 
Dingman 1973). A few days after peaking, the 
runoff from melting subsides greatly. Since 
much of the subdued tundra terrain was ob- 
served to be waterlogged during a considerable 
time after the snowmelt in 1972 and 1973, but 
with decreasing depths of the standing water, it 
seems likely that a substantial amount of the 
meltwater evaporates from the tundra surface 
each year, although part of the meltwater may 
infiltrate the active layer. Observations on the 
Meade River and in the Noluck Lake region 
indicate that much of the snow may disappear 
before runoff occurs (Benson 1969; Johnson 
and Kistner, 1967). 
Concluding Remarks 
The seasonal snow cover on the Arctic Slope 
near Prudhoe Bay contains about 10 cm water 
equivalent. The snow in the Brooks Range is 
about three times this amount. The snow is 
subject to drifting from east and west winds; the 
west winds are more effective than the east 
winds as snow drifters. Dust is blown onto the 
snow from the channels of the Sagavanirktok 
River and, after April, from roads which have 
traffic. The dust from roads is proportional to 
the amount of traffic (see sequential photo- 
graphs). The riverbed and adjacent dune areas 
produce much more dust than do the roads. The 
east winds are more effective than the west 
winds as dust movers. 
The first melt action produces ice lenses, 
layers, and glands in the snow. These are imper- 
vious to airflow and -produce structural and 
thermal effects that may be significant to ani- 
mals such as lemmings, which live under the 
snow. The melt that produces these ice masses 
may come a month before the temperature of 
the entire snowpack is raised to the melting 
point. The thaw period proceeds by rapid melt- 
ing of the snow from centers of ablation such as 
