Document 11455466

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CHAPTER SUMMARY
The polar oceans and seas have keen a lure for the explorer and scientist ever since the
first w h a k and sealers identified them as rich hunting grwnds. Organisms living here
are adapted t o tow temperatures, long periods in the year of poor light and an e ~ o system dominated by the seaswral formation, consolidation. and subsequent n-eltof a
layer of frozen seawater that can be more than 10 m thick. The effects of global climate
change are likely to have prafound influences on these regions, but our understanding
of their ecology, and therefore the potential threats of climate change, is still rudimentary due Largely to the hatile working conditim. Like ather extreme e n v i m m e a
the metabolic and physiological adaptatiam that enable life to go on are a potential
source for novel biatechnol~icala~lications,and polar organisms, in particular m i m
organism, are also potential proxies for life on extraterrestrial systems.
11.1 Introduction
Cold, hostiIe, barren white wastelands would be a fairly
impression of the frozen pack ice that covers polar oceans and se
image is reinforced during the long polar winter when, if the sun
rise above the horizon, the fleeting hght is no more than dull dreary
light. Even in summer, snow blizzards can descend with no war
forming condtions ofsuch poor visibility that it is impossible
a few centimetres in front of you. It is of course not all gloom
despondency a d even in the bleak winter ethereal displays of
boreab (inthe North) or aurora australis (in the South),I
in electromagnetic pyrotechnic displays that enhance the feel
in a part of a world governed by physical forces quite disco
the rest of the Earth.
At its maximum ement area pack ice (Fi11.1) can cover an area
prising 13% of the Earth's surface making it a biome that comp
h o s e of the rundra and deserts. O u ~ d o
ef the polar circles, sea i
an ephemeral &cure of the Baltic, Caspian, and Okhotsk Seas.
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