3.3.9. Infrastructure, Settlements, and Health
The climate dictates many aspects of the way of life for all people living
in the Arctic. Climate changes are likely to affect the current subsistence
economies, habitability, and health of the Arctic people. If warming occurs,
there will be striking changes in the landscapes at northern high latitudes.
These changes may be exacerbated where they are accompanied by growing numbers
of people and increased economic activity (IPCC 1996, WG II, Chapter 7 Executive
Summary). There could be a northward spreading of agricultural, forestry, and
mining activities-resulting in increased population and intensified settlement
patterns-into Arctic areas. The rate of such spread is an issue of debate and
will depend on social and economic factors, intervention strategies, and natural
processes. Marine, road, rail, and air links would have to be expanded accordingly.
Although this development would entail substantial extra capital and operating
costs, it also would be an economic opportunity (IPCC 1996, WG II, Section 11.4.4).
Changes in landscape, sea-ice distribution, and river and lake ice could have
a major impact on indigenous people who live in Arctic regions and depend upon
traditional occupations, food gathering, and hunting. They depend directly on
the living resources of the area and often travel on ice, so their livelihood
may be widely affected. The resulting redistribution and abundance changes of
terrestrial and marine animals that are vital to the subsistence lifestyles
of Native communities may have major impacts. Ice roads and crossings commonly
are used to link northern settlements. The greatest economic impact is likely
to stem from decreases in ice thickness and bearing capacity, which could severely
restrict the size and load limit of vehicular traffic (IPCC 1996, WG II, Section
7.5). Road maintenance related to permafrost thawing already is a major problem
with high associated costs in many sub-Arctic areas. At the same time, further
warming is likely to cause many small settlements, particularly along the coast
and on small islands, to be abandoned because of permafrost loss and sea-level
Anticipated hydrological changes and reductions in the areal extent and depth
of permafrost could lead to large-scale damage to infrastructure. Some transportation
systems, mining activities, and structures will be threatened by thawing (IPCC
1996, WG II, Section 7.5.1). For example, thawing could lead to disruption of
existing petroleum production and distribution systems in the tundra unless
mitigation techniques are adopted (IPCC 1996, WG II, Chapter 7 Executive Summary).
This impact may require changes in the design of oil pipelines to avoid slumping,
breaks, and leaks (IPCC 1996, WG II, Section 11.5.4). Fortunately, most of this
technology already is in use south of the permafrost line.
Structures such as pipelines, airstrips, community water supply and sewage
systems, and building foundations are susceptible to performance problems if
existing frozen foundations or subgrades thaw, even minimally. Extensive measures
would be needed to ensure the structural stability and durability of installations
for tourism, mining, and telecommunication in permafrost areas affected by climate
warming. In some cases, existing settlements would become uninhabitable because
of permafrost changes. Transport links also could be affected, with serious
disruption and increased maintenance costs from ground subsidence, side-slope
slumpings, landslides, icings, and ice-mound growth.
On the other hand, many northern cities will spend less money on snow and ice
clearance. More frequent periods of open water for rivers, lakes, and seas,
however, will produce greater snowfall downwind. This factor will be important
near Hudson Bay, the Barents Sea, and the Sea of Okhotsk (IPCC 1996, WG II,
7.4.1). Engineering design criteria will need to be modified to reflect changing
snow and frost climates, deepening of the active layer over permafrost, and
warming and ultimate disappearance of marginal or discontinuous permafrost.
Present permafrost engineering commonly designs for the warmest year in the
past 20 years of record; such criteria may need to be reviewed and revised (IPCC
1996, WG II, Section 7.5.1).
Sea-level rise will affect a few outlying Arctic communities, many of which
are on the shoreline, as well as major coastal industrial facilities such as
the Prudhoe Bay oilfields in Alaska. Sea-level rise also will allow ice-thrust
events to be more damaging to the shoreline. Coastal permafrost will be thermally
eroded, which will produce local slumping and coastal retreat.
Episodes of extreme cold and blizzards are major climate concerns for circumpolar
countries like Russia and Canada (IPCC 1996, WG II, Section 220.127.116.11). However,
the Polar regions will remain cold, so the direct effects of global warming
are likely to have little effect on human health. Potential indirect effects,
such as changes in infectious diseases and vector organisms, are largely unknown.
UV-B radiation is increasing, which can damage the genetic (DNA) material of
living cells (in an inverse relationship to organism complexity) and induce
skin cancers in experimental animals. It also may affect human health: UV-B
radiation is implicated in the causation of human skin cancer and lesions of
the conjunctiva, cornea, and lens; it also may impair the body's immune system
(IPCC 1996, WG II, Section 18.4).