Table 8. Joint Ice Center's sea ice severity data for Alaska's north coastal
waters (from USN/NOAA NIC 1994).
Initial opening date of coastal route to Prudhoe Bay*
Length of navigation season (days)
NA† 7 Nov
Final closing date
Number of days route entirely ice free
Distance (nm) from Pt. Barrow northward to:
Ice edge on 10 August
Heavy pack edge** on 10 August
Ice edge on 15 September
Heavy pack edge on 15 September
* Opening date based on the initial date that the entire route from the Bering Sea to Prudhoe
Bay may be navigated through ice cover of less than 5/10 concentration.
† No closing date in 1975 because the route never opened.
** Boundary between greater than 5/10 ice cover to the north and less than/equal to
5/10 to the south.
varied between 19 July and 3 September. The
INSROP Working Paper I.1.1
length of the navigation season also varies consid-
A paper by Kjerstad (1994) published by the
erably, as shown in Appendix C. In 1975, the route
International Northern Sea Route Programme pro-
never opened, whereas in 1993 it was considered
vides perhaps the latest information publicly avail-
navigable (5/10 ice concentration or less) for 112
able on navigation guides, regulations, operational
days. Table 8 presents the means and extremes of
aids, and communication systems. Though we did
sea-ice conditions affecting navigation in north-
not receive it in time to thoroughly review and
ern Alaskan waters from 1953 through 1993.
incorporate its contents into this report, the inter-
ested reader is advised of its existence and from
where it can be obtained (see Literature Cited).
THE NAVIGATIONAL SETTING
Routes, distances, and depths
The overall distance from one end of the NSR
to the other is variable because of the choice of
routes available. Due to variable ice and hydro-
DMA sailing directions
graphic conditions, longer routes may be more fa-
The Defense Mapping Agency Hydrographic/
vorable in terms of the time required for passage.
Topographic Center in Bethesda, Maryland, pub-
Figure 20 shows the distances between various
lishes and sells a series of detailed sailing direc-
waypoints along the route. In general, the shorter
tions for the entire globe. Navigational details for
(in distance) transit routes between Novaya
the NSR are described in the Agency's Publication
Zemlya and the Bering Strait are the northern vari-
183, Sailing Directions: Northern Coast of Russia
ants. These routes need to be weighed against the
(DMA 1993). In addition to sailing directions, this
likelihood of more severe ice conditions to be found
publication provides important information about
farther off the coast.
the region's river and seaports.
The Russian Arctic is characterized by expan-
sive seas (the Kara, the Laptev, the East Siberian,
Russian State Hydrographic Department
and the Chukchi) separated by island archipela-
The State Hydrographic Department under
goes (Novaya Zemlya, Severnaya Zemlya, Novo-
Russia's Ministry of Transport has, since the for-
siberskiy, and Wrangel), with several routing
mal opening of the route, been compiling an offi-
choices around or through each. The choice of route
cial NSR navigation guide for foreign consump-
is determined by several factors, including the voy-
tion. It is to be published as the Guide to Navigation
age origin and destination, the current ice condi-
Through the Northern Sea Route, and was described
tions or those to be expected based on meteoro-
earlier (see Administration and Regulations). Our
logical and hydrodynamic forecasting, and the
draft translation of this document served as a ma-
location of icebreaking resources at the time.
jor source of the information presented below.