Mountain permafrost exists in different forms.
Rock glaciers such as this one in the Northern
Tien Shan Mountains of Central Asia are a phe-
nomenon of actively creeping, ice-rich mountain
permafrost under a cover of debris.
Photo: S. Marchenko
Building on permafrost in northern
Canada
Permafrost and its ground ice present challenges
to infrastructure development in northern Canada.
Development of infrastructure disturbs the ground
surface and changes the heat flow in the ground,
causing thawing of ice-rich permafrost which in turn
de-stabilizes the ground
9,60
. Current engineering prac-
tices consider permafrost and aim to minimize the
impacts of thaw. Climate change, however, presents
an additional challenge as warmer conditions may
enhance the impacts of infrastructure development
on the heat flow in the ground. The design of exist-
ing structures may not account for additional perma-
frost thaw resulting from climate changes. It is hard
to tell if recent warming has already had an impact
on existing infrastructure in Canada. It is difficult to
separate the effects of climate change from the ef-
fects of construction and operation of a structure,
which tend to be of greater magnitude
61
.
Climate change, however, is now recognized as a con-
cern over the lifetime of major development projects
in northern Canada and has been included in engi-
neering designs since the late 1990s. A screening
Trends and outlook for high altitude
tool has been developed by a working group of scien-
(mountain) permafrost
tists and engineers
62
to assess the level of analysis on
climate change needed for a particular project. It is
also required to consider climate change in the envi-
Europe
ronmental assessment for major projects, especially
long-term ones
63,64
. For example, climate change was
Significant amounts of mountain permafrost exist in Sval-
recognized as a concern for the Ekati Diamond Mine bard, Fennoscandia, the Urals, the Caucasus, the Pyrenees,
which opened in 1998, and potential climate change the Alps, and Iceland. Data from a north-south line of
impacts were considered in the design of the mine’s
boreholes, 100 m or more deep, extending from Svalbard
waste storage
65
. The proposed Mackenzie Gas Pipe-
to the Alps show a long-term regional warming of perma-
line has considered climate change in both its design
frost of 0.5–1.0 °C
66
during recent decades. In Scandinavia
and environmental assessment.
and Svalbard, monitoring over 5–7 years shows warming
192 GLOBAL OUTLOOK FOR ICE AND SNOW