Media playback is unsupported on your device Media caption Close-up: The new icebreaker. Footage and images courtesy NERC/BAS

UK science is to get one of the biggest, most capable polar research vessels in the world.

The £200m investment in an icebreaker was announced by Chancellor George Osborne in a speech in Cambridge.

The ship is likely to be 130m long and sport a helipad, cranes, onboard labs, and have the ability to deploy subs and other ocean survey and sampling gear.

It should be ready to enter service in 2019, and will support scientists in both the Antarctic and the Arctic.

The strength of its hull will allow it to push deeper into pack ice than any previous British research vessel.

Infrastructure needs of science George Osborne has committed an inflation-linked £1.1bn per year to be spent on science infrastructure through to 2020-21. A consultation with the science community will now determine where that money will go. The chancellor listed some disciplines that could benefit - from the search for dark matter to fusion energy, from phenomics to robotics. But it wasn't for government to choose, he said: "It's over to you. The government is committing a historic £7bn to science investment. We're asking you, the science community, and the business community too, how best to invest that funding, how to maintain excellence and where are the new opportunities that will put Britain ahead in the global race?" The consultation will report back in the autumn.

Initial technical specifications require the ship to be able to maintain a speed of three knots while breaking through 2m-thick floes.

The money to build and equip the vessel is coming from the government's capital investment fund for science, for which Mr Osborne has committed over £7bn between now and 2020-21.

Addressing an audience at the world-famous Laboratory of Molecular Biology in Cambridge, the chancellor said science was at the core of rebalancing the UK economy: "I get that this is something that Britain is brilliant at, and that it's vitally important to our economic future. So I've made it my personal priority in government to support [scientists in their] endeavour."

Mr Osborne added that there would now be a consultation on how best to spend the £7bn science infrastructure monies.

The UK already operates two polar ships - the Royal Research Ship (RRS) James Clark Ross and the RRS Ernest Shackleton.

The former was built in 1990 and the latter in 1995.

Media playback is unsupported on your device Media caption Sir Paul Nurse: "We need to be bold and ambitious"

A case was made to government, and accepted, that this fleet needed to be augmented with a more modern capability if the nation's science at high latitudes was to remain competitive.

An early design concept for the new ship has been drawn up by naval architects, but this will need to be finessed.

A clear imperative is that the final design features a helideck - something omitted on the Clark Ross and which experts have told the BBC is really essential for effective Antarctic operations.

Precisely where the ship will be built is an open question.

Given the scale of the investment, a home shipyard would obviously be preferred. But European Union rules will require that bids also be invited from beyond the UK.

Image caption The poles are at the forefront of climate research

There is sure to be some concern that the announcement of the new vessel will signal an imminent reduction in the fleet - one super ship to replace two ageing vessels.

But the Natural Environment Research Council (Nerc), which funds polar science in the UK, says this is not the current plan.

The desire is to operate both the Clark Ross and the Shackleton until at least the end of the decade, it states.

A decision will then be taken on what to do with the Shackleton, which, unlike the Clark Ross, is not British-owned but leased from a Norwegian company.

The first of five available one-year extensions to this bareboat charter arrangement comes into effect in August.

Analysis Global warming does not mean an end to polar ice nor to the need for icebreakers. Even if the Arctic becomes largely ice-free in summertime later this century, as the latest science suggests, the legacy of each winter's deep freeze will still litter the ocean - some of the jagged shards of ice will be visible but many will bob treacherously just below the surface. While reporting on an expedition through Canada's fabled Northwest Passage in October 2007, I woke to the sound of an unnerving clanging along the hull. The vessel, the Amundsen, was pushing through pack ice and each jolt and reverberation made me wonder about the strength of the steel. But to understand how the polar regions are changing, and the implications for everything from wildlife to fishing to new oilfields to future shipping routes, the view from space offered by satellites is not enough. For decades to come, the most detailed research will require tough vessels to venture into the midst of what has become a messy and hazardous scene.

Nerc has made it clear also that the capital investment for the new ship will not impact the budget for its day-to-day science or ongoing infrastructure needs. The investment is on a separate government line.

The council has recently upgraded its "bluewater fleet" - the open-ocean vessels RRS Discovery and RRS James Cook are both less than 10 years old.

Prof Duncan Wingham, the chief executive of Nerc, told BBC News: "The new vessel will make Nerc's entire fleet, ton for ton, the most advanced scientific fleet in the world.

"The new ship will be a clear statement of the UK's commitment to science in the Antarctic and South Atlantic, and increases our ice-breaking capability in the south and, just as important, in the Arctic."

Sir Paul Nurse, the president of the Royal Society, welcomed the "fantastic" investment in polar science, and said it showed the chancellor "really does get it".

"Of course, we're still not the biggest spenders on science; we still look at the US, at Germany and South Korea, who are all investing more," he added.

"I'm hoping we'll be able to persuade the chancellor, not only to maintain where he is but also to increase the investment so we can really compete with those countries."

What the new polar ship promises to be like

Image copyright NERC/NERC

Likely to have a length of 130m and a breadth of 25m

Its gross tonnage would be about 13,000 tonnes

Its cargo volume would be around 4,200 cu metres

It must be self-sufficient to operate for up to 80 days

This means it could cover roughly 24,000 nautical miles

Helicopter facilities are today considered a must-have

It would launch aerial and ocean robotic systems

Up to 60 scientists and support staff could live aboard

Image copyright BAS Image caption This is just an early design concept. The details will need to be finessed

UK's existing polar research vessel capability

Image copyright BAS Image caption The RSS James Clark Ross is now almost 25 years old and has no helicopter capability

James Clark Ross (above) was built on Tyneside and is UK-owned

Ernest Shackleton's bareboat charter has just been extended

Both are flagged in the Falklands but operate in the north too

They resupply Antarctic bases, including remote Halley Station

Image caption The British Antarctic Survey operates a number of southern stations

Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos