By Matt McGrath
Environment reporter, BBC News
One of the world's biggest research programmes of the past 50 years has been launched in Paris.
International Polar Year (IPY) is a $1.5bn (£763m) collaborative effort to study the north and south poles.
Thousands of researchers will be carrying out more than 200 projects, with climate change top of the agenda.
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One of the key questions that scientists will hope the research effort will shed new light on is the potential rise in sea level caused by melting of ice sheets in Greenland and Antarctica.
The southern polar ice sheet holds 90% of the world's fresh water. If it all melted, global sea levels would rise by 60m (197ft).
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more:
http://news.bbc.co.uk/2/hi/science/nature/6406735.stm(Basically an update of earlier news, but I like those last two paras.)