I. INTRODUCTION 
During the past 3 years, the Ue S. Navy Hydrographic Office has 
been providing ice forecasts in support of military operations in the 
Arctic. These forecasts include information on the distribution, growth, 
and disintegration of sea ice, and other predictable factors which serve 
as aids to such operations. The forecasts are divided into two classes 
(a) shorterange (l8-hour) forecasts designed to provide detailed ice in- 
formation for the field units while operating in the ice and (b) long= 
range (5-day to 6-month) forecasts designed for operational planning. 
Forecasts of ice conditions in open-water areas present problems 
which involve oceanographic and meteorological factors that simultane- 
ously influence major areas. Conditions in the open water are suffi- 
ciently homogeneous so that forecasts can cover large areas. However, 
the local topography influences the various oceanographic and meteorologi-= 
cal factors for each harbor site. Separate ice studies are contemplated 
for the various harbors in which military shipping is conducted. These 
reports will describe the special local factors which affect ice fore= 
casting in each harbor, so that the local sequence of freezeup and ice 
growth can be delineated and a study of the particular harbor will be 
available for future operations. The present report discusses the local 
conditions of North Ster Bugt and Wolstenholme Fjord, Greenland. 
North Star Bugt, which is approximately three square miles in area, 
is situated in a protected cove opening to the west. A narrow peninsula 
to the north separates this bay from Wolstenholme Fjord, into which large 
glaciers discharge from the inland icecap. The peninsula terminates with 
the spectacular landmark, Mount Dundes, which is over 700 feet high, Hills 
about 1,000 feet high lie close to the south and east of the bay. Between 
these hills, Pitufik Valley (local name) extends to the east-southeast 
with a relatively gentle slope. Geographic features of the area are 
shown in figure i. 
The bay is normally open to shipping for three months anmually (5 
July to the first week of October). These dates vary somewhat from year 
to year, depending on the influencing factors. During the first half 
of July, shipping is almost entirely dependent on icebreaker escort. 
Obstructions to shipping are caused largely by the presence of sea ice, 
since ice of land origin is not of sufficient concentration to present 
a navigational problem. 
If. CLIMATOLOGY 
The warmest air temperatures at Thule occur during July with a 
mean temperature of 2° F, The coldest air temperatures occur during 
February with a mean temperature of ~159 F. The total precipitation 
throughout the year averages about 2.5 inches, nearly half of this amount 
