By Mark Kinver
Science and nature reporter, BBC News
For the next two years, one of the largest international research programmes for 50 years is going to focus on the world's most remote regions - the Antarctic and Arctic.
The International Polar Year (IPY) brings together thousands of scientists, from more than 60 nations, to participate in more than 200 projects.
And the issue at the top of the agenda is climate change.
"This is going to raise the profile of the issue of global warming among the international community," said Sir David King, the UK government's chief scientist.
"We know that what is happening to ice on the planet is a very clear indication of what is going to happen to the rest of us.
"If you like, ice is the canary in the coal mine for global warming."
Sir David made his comments, via video message, to the UK launch of IPY.
The event, at the Royal Society, London, was the first in a series of events around the world to mark the start of the fourth international study of this kind.
The first IPY, held in 1882-83, saw the world's first co-ordinated international expeditions to the polar regions.
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In 1932-33, the second IPY led to 40 permanent observation stations being established in the Arctic.
But the most successful was the 1957-58 study, otherwise known as the International Geophysical Year (IGY).
Successes credited to IGY include the discoveries of the Van Allen radiation belts that surround the Earth, and the launch of Sputnik, the world's first artificial satellite.
IGY was also said to be fundamental in establishing the Antarctic Treaty, an international agreement that designated the region as a continent for peace and science.
Royal Society president Lord Rees, speaking to reporters, said the fourth IPY would build on scientists' current knowledge.
"Polar regions are clearly the focus of even more interest than they were 50 years ago when those of an older generation remember the previous International Geophysical Year.
"That is because of a number of reasons," Lord Rees explained. "They are the most pristine and least explored parts of the planet.
"Climate change is also more manifest here than anywhere else, and some of the best data on the climate comes from what we get from the ice cores."
Cynan Ellis-Evans, head of the UK's IPY national committee, said British researchers were involved in half of the 170 science projects.
"The UK is contributing in a variety of ways, from leadership in some projects to providing to the infrastructure of others. Certainly, we are among the top five or six nations involved in IPY."
Although much of the research would build on existing research programmes, Dr Ellis-Evans said there would be extra funding to promote international co-operation.
"The IPY is going to be taking this large number of nations and work together," he said. "One classic example is the Census of Antarctic Marine Life, involving 18 nations."
The project will investigate the distribution and abundance of marine biodiversity in the region, and aims to provide a benchmark against which future changes, including climatic shifts, can be measured.
"The whole of the Southern Ocean is going to be covered, and this sort of activity would never have been possible outside of the IPY," Dr Ellis-Evans added.
At the beginning of February, the Intergovernmental Panel on Climate Change (IPCC) published a summary of its Fourth Assessment Report, which showed that human activity was "very likely" to be causing climate change.
But it added that uncertainties still surrounded some of the projected impacts, such as sea level rise caused by melting ice-sheets.
One of the speakers at the launch in London said that the IPY would address these issues.
Eric Wolff, principal investigator for the British Antarctic Survey, used a musical analogy to make his point.
"Scientists study these things all the time but the way I like to think of it is that individual musicians sound interesting to listen to," Dr Wolff said.
"But it is only when you put them all together with a conductor in an orchestra that you start to hear something fantastic.
"And that is what the IPY is going to do; it will allow us to look at the whole in one go and get a snapshot."
IPY will be officially launched in Paris on 1 March, and will run until March 2009.