Why should there be so much excitement over the discovery — from the log books of two of Britain’s most famous explorers more than 100 years ago — that there was the same amount of ice floating round Antarctica then as there is today?

To the surprise of academics from the University of Reading, the records kept by the expeditions of Captain Robert Scott and Sir Ernest Shackleton in the early years of the last century — which detail the extent of ice cover, the state of the sea and the weather — show there has been remarkably little change in the extent of sea ice at the other end of the world.

Dr Jonathan Day, who led the study, said: ‘The data collected by these and other explorers could profoundly change the way we view the ebb and flow of Antarctic sea ice.

‘We know that sea ice in the Antarctic has increased slightly over the past 30 years, since satellite observations began.

‘Scientists have been grappling to understand this trend in the context of global warming, but these findings suggest it may not be anything new.’

Passengers from the Russian ship 'Akademik Shokalskiy' explore the frozen Ross Sea in the Antarctic. Mount Erebus volcano is in the background

Capt Laurence Oates, Capt Robert Scott, Petty Officer Edgar Evans (standing, left to right), Lt Henry Bowers, Dr Edward Wilson (sitting, left to right). Polar explorers remembered as 'heroic failures' have provided crucial proof that sea ice around Antarctica has barely changed in size - 100 years after their expeditions

The relevance of this startling discovery is that it again raises question marks over what has become the single most influential scientific theory shaping our modern world: the belief that the planet is dangerously overheating and we need to take drastic steps to bring it under control.

Those who believe in man-made global warming are passionate in their belief that, thanks to those supposedly soaring temperatures, the mighty polar ice caps are melting rapidly.

If this continues, the theory runs, it could lead to a rise in sea levels so great that it would eventually flood many of the most densely populated regions of the world.

No sequence in the film An Inconvenient Truth — made by the former U.S. Vice President Al Gore — was more chilling than his computer graphics showing how melting ice could cause the oceans to rise by 20 ft, drowning many of the world’s great cities, from Shanghai and San Francisco to New York and London.

It is true that, in the past 37 years since satellite records began, the summer ice at the top of the world, in the Arctic, has been shrinking — though nothing like as far or fast as has been constantly predicted.

But even if all that floating sea ice did melt, it would do no more to raise sea levels than the melting of an ice cube in a gin and tonic raises the level of liquid in the glass — in other words, barely at all, because the volume of the ice is replaced by a similar volume of water.

Aerial view of the GAUSS in the ice during the German Antarctic Expedition

The Russian ship MV Akademik Shokalskiy is trapped in thick Antarctic ice 1,500 nautical miles south of Hobart, Australia

Potentially much more serious in terms of the planet’s future is the colossal amount of land ice on Antarctica, which contains 90 per cent of all of the ice on the planet.

And it is here that we find what is arguably the single most glaring contradiction in the global warming theory.

Because all the evidence suggests that, far from getting warmer, over the past 50 years Antarctica has, in fact, been getting colder.

The satellite records show sea ice around that mighty continent has been increasing to the point where last year, it reached its greatest extent since Nasa’s observations began in 1979.

Even more significant was another finding reported by Nasa last year, showing that the thickness of ice over most of that vast continent has been making colossal gains — as much as 112 billion tons a year between 1992 and 2001, and an average of 82 billion tons a year between 2003 and 2008.

For years, the global warming zealots remained so convinced of their theory about melting ice that they simply shut their eyes to what is really happening at the bottom of the world.

There was a farcical example in 2013 when an Australian-led ‘scientific expedition’ sailed into the Antarctic Ocean to study how quickly climate change was melting the ice.

Robert Falcon Scott (1868-1912), British naval officer and explorer of Antarctica, standing in the snow and holding a ski pole (left) and on skis in the snow

On-board the Russian ship were 18 scientists from Australia and New Zealand, plus assorted green campaigners who had paid to go along as ‘science assistants’, along with journalists from the BBC and the Guardian newspaper, who helped sponsor the trip.

As Christmas approached, they ignored their Russian captain’s warning that the ice was closing in so fast that they should escape.

They continued to frolic around on ice thickening around their ship to more than 10 ft while, according to the BBC man, they were still taking measurements ‘to show how quickly the Antarctic’s sea ice is disappearing’.

Eventually, they became so dangerously trapped that they had to be helicoptered to a Chinese rescue ship, which, itself, became so stuck that it had to be rescued by an American ice-breaker.

Many attempts have been made by less reckless scientists to persuade the world that Antarctica is warming, though their efforts have focused almost entirely on the one part of that vast continent which has, indeed, become slightly warmer — its western coast.

It is from here we have seen dramatic shots of melting glaciers crashing into the sea.

But more cautious experts have tried to explain this is because of heat rising from a mighty crack in the Earth’s crust buried far beneath the surface.

File photo of the SS Terra Nova which took Captain Scott to the South Pole

The efforts of global ‘warmists’ to turn the evidence on its head have bordered on the comical.

In 2009, scientific luminaries of the UN’s Intergovernmental Panel on Climate Change produced a paper in advance of what was to be the most important climate conference the world had ever seen.

Their sensational study was part of a general bid to whip up climate hysteria before the world’s leaders met in Copenhagen that December to discuss a treaty committing them to every kind of drastic measure to halt global warming.

The paper claimed to show that, far from getting colder, as all previous evidence suggested, Antarctica was getting warmer.

Almost immediately, however, other experts spotted a fatal flaw in the study. It had all hinged on temperatures recorded by a single weather station.

But pictures of this place showed it buried under snow, which would have cocooned its thermometers from the freezing outside air, giving readings distinctly warmer than they should have been.

Of course, the discovery that emerged this week from the records kept by Shackleton and Scott supports what we already knew from modern research — that what is going on at the bottom of the world is the most embarrassing single flaw in the whole global warming theory.

Isn’t the whole point about ‘global warming’ that it is meant to be ‘global’?

So how does that stack up when Antarctica appears to be cooling, its sea ice has been growing so fast there is more of it than at any time since records began and it has been confirmed scientifically that the thickness of its land ice has been increasing by trillions of tons?

And why is all this of much more than just academic interest to the rest of us?

Because it is the widely held belief in human-made climate change that is persuading our politicians to plan the most extraordinary revolution, not just in how we make our electricity, but in our entire way of life.

The next time you are shocked at how fast your energy bills are rising, or you pay an extra £70 tax on an airline ticket thanks to a green levy, or see another row of giant windmills looming over the countryside, you might think of the great puzzle of Antarctica.