Natural disasters
Impacts of natural hazards, combined with extreme polar climatic conditions
(low temperatures, short summers, extensive snow and ice cover in winter),
and vulnerable ecosystems and infrastructure can easily result in disasters
in the Arctic. For example, during the five-year period 1996-2001, there
were two catastrophic floods in the Lena River that exceeded all previous
records. In the winter of 2001, temperatures hit a record low, some rivers
froze solid, and therefore took longer to thaw, and blocks of ice clogged
the natural flow. In addition, in that year, the snowfall was particularly
severe. The water levels in the central part of the Lena exceeded the
normal average by 9 metres or more. Economic losses and environmental
devastation were severe (Kriner 2001a, b). Because climate change is likely
to increase precipitation in the catchment areas of Arctic rivers (IPCC
2001a), there may be a corresponding increase in the frequency and magnitude
of floods.
The temperature increase observed over the Arctic land masses in recent
years results in permafrost thawing in many areas. In the developed areas
of the Arctic, efforts will be needed to reduce the impacts of thawing
on buildings and transport infrastructure (IPCC 2001b). The permafrost
zone covers 58 per cent of the Russian Federation. The zone border may
move 300-400 km northwards by 2100 (Interagency Commission 1998).
Another natural disaster affecting the Arctic ecosystem is pest invasion,
which can devastate a forested area and affect the related economic activities.
Pest outbreaks are a major problem in the forest-tundra zone. The spruce
bark beetle (Dendroctonus rufipennis) has caused serious destruction
and forest death in the spruce forests of Alaska. In Scandinavia, autumn
moths (Epirrita autumnata) cause massive defoliation of birch forests
at about 10-year intervals. These forests do not recover for up to centuries
because of the slow recovery rate of vegetation in the Arctic (CAFF 2001).
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