Arctic Yearbook 2012
Shipping and Resources in the Arctic Ocean
264
freedoms of the High Seas and where all parties shall have due regard to the rights and duties of
other states and where all are obligated to act in a manner compatible with the spirit and letter of the
Convention. Thus, the biggest chunk of Arctic water is that which is designated the High Seas. The
direct distance across the Central Arctic Ocean from the Bering Strait across the North Pole to the
Fram Strait is 2100 nautical miles.
Contrary to popular belief, the ice cover of the Central Arctic Ocean is not a static unbroken surface.
It is constantly in motion, breaking into pieces, and building up pressure ridges above and below the
surface where floes grind together. Because of the cleavage of the sea-ice canopy, leads and areas of
open water (called polynyas) and thin ice (called skylights) are present all year round. As early as in
the 1960s (before the global warming of the present was recorded) these open water areas
constituted from 5 to 8 per cent of the total area of the Arctic Ocean during the winter season, and
approximately 15 per cent during summer (Molloy, 1969). The distribution and frequency of
polynyas and skylights are random, but they appear even in the vicinity of and at the very North Pole
throughout the year. Some of the leads and skylights in the vicinity of the Pole were assessed to be
nearly half a mile in diameter (Calvert, 1960; Dyson, 1963).
The sea ice varies in shapes, thicknesses, ages and hardness, presenting different challenges to
navigation. Expert opinion is that the present thawing is long-term and that the ice-edge will steadily
migrate northward along with a further thinning and weakening of sea ice. The northern movement
of the ice edge will gradually make the southern margins of the Arctic High Seas (within the 188 n.m
belt) available for navigation, i.e. along the
high latitude-route
claimed to be part of the NSR (see
section “The Official Russian Definition of the NSR”, above). Over the last 30 years, sea ice
thickness in the Central Arctic Ocean has decreased by 42%, a decrease of 1.3 m – from 3.1 to 1.8 m
(Weller, 2000: 40), with an accompanying reduction of some 73% in the frequency of deep pressure
ridges in certain places (Wadhams, 2004). As a consequence, the influx of multi-year ice from the
Central Arctic Ocean to the coastal areas, in particular to the NSR, has decreased by 14 per cent
from 1978 to 1998 (Wadhams, 2004).
On the basis of these and other scientific observations, model experiments suggest a further decrease
in sea ice thickness of some 30 per cent, and an ice volume decrease between 15 and 40 per cent by
2050 (NOIFA, 2001: 3). If this trend continues, one postulate is that summertime disappearance of
the ice cap is possible in the course of this century and that significant areas of the Arctic Ocean may
become permanently free of sea ice in summer (NOIFA, 2001). One of the models simulates an ice-