GPS markers usually pinpoint a spot on the earth’s surface to help everything from map-making to navigation.

This one (left) spectacularly didn’t.

In fact, it wandered hundreds of miles (km) this year on an iceberg, blown by winds or carried by ocean currents in huge pirouettes off the coast of Antarctica.

When glaciologist David Vaughan (above) of the British Antarctic Survey stuck the pole holding the GPS (global positioning system) tracking device into the Wilkins Ice Shelf in Antarctica in January, the ice felt solid as rock.

Stuart McDill of Reuters TV and I had landed with him in a small plane mounted with skis on a 40-km-long floating ice bridge which had been in place probably for thousands and thousands of years. But it was weakening and about to snap in what Vaughan said was a sign of global warming.

We didn’t stay long.

The GPS marker was meant to transmit its position to satellites to help monitor movements in the ice shelf — up to about 250 metres thick — to measure the strains before it finally cracked up. The ice bridge shattered in April and collapsed into a swarm of icebergs.

But surprisingly, the GPS kept on going for months — broadcasting its position as a lone metal spike that may have puzzled passing penguins or the odd whale. The diagram above shows where it began (near top right by Charcot Island and then southwest until its last transmission on Aug. 30. No one knows its fate - maybe the batteries gave out or its iceberg cracked up.

The GPS did far better than planned. Vaughan had been convinced that the GPS, set up for Michiel van den Broeke of Utrecht University and colleagues, was not going to work at all. After he set it up, it went “beep beep beep” to signal that it was OK but then fell silent.

We all thought it had failed; we didn’t know that it was programmed to beep only briefly to show that it worked — too many beeps would have drained the batteries.

(Picture: REUTERS/Alister Doyle, diagram: Roderik van de Wal, Utrecht University, Matthias Braun, Bonn University) 

It’s not often you go to a part of the world that disappears from the map a few weeks later.

Luckily we weren’t on the Wilkins Ice Shelf (above) in Antarctica on April 4, when an ice bridge that may be holding ice the size of Jamaica in place shattered into dozens of giant pieces (story here).

The break-up was captured on satellite images by the European Space Agency  (below left from today, with an image of the ice bridge intact from April 2, below right)

But we were there in January — Stuart McDill of Reuters TV and I travelled with a group of scientists from the British Antarctic Survey who landed on the flat-topped ice in  sunshine in a bright red Twin Otter plane. (main photo above: the ice cliff at the front is about 20 metres high. Photo below left shows the plane on the ice).

 It was the first, and last, visit by anyone to an area that has now cracked into a chaos of giant icebergs. We landed just by the narrowest part of the strip that stretched from Charcot Island southeast to the coast of Antarctica.

Even in January, the scientists led by David Vaughan of BAS were reluctant to linger because of a risk of cracks in the ice. The shelf may well have been there for thousands of years.

Using a plane with skis instead of wheels, we landed close to the narrowest part — only about 500 metres wide; David set up a GPS monitoring device (wonder what’s happened to that?) and the rest of us gazed in amazement around the flat-topped ice. 

It seemed so stable, so permanent, that it was hard to imagine it might vanish. The ice is hundreds of metres thick, most of it below the water. We’d been waiting for several days for the weather to clear — it was a glorious day with blue skies and temperatures above freezing.

 But the ice bridge — about 100 km wide in 1950 — has steadily shrunk since the 1990s, with global warming caused by human use of fossil fuels the main suspect. Sediments taken beneath some other collapsed ice shelves to the north show that they have been in place for at least 10,000 years.

But the danger is that, when ice shelves break up, the ice on land behind them in glaciers will start accelerating towards the ocean, adding water that will raise sea levels. The Wilkins is an exception in that it does not have much pent-up ice behind it.

But there are far bigger ice shelves to the south that do.

Most times writing about the environment means a glacial pace of change.

 Sometimes, something snaps.

 Meteorologist Tamsin Gray releases a weather balloon at the British Rothera research station on the Antarctic Peninsula to help record temperature and other data from the freezing air. Apart from helping predict the weather, the balloons are also giving scientists clues to global warming.

As you can see, it starts off about 2 metres across but how big it is when it reaches about 25 km above the ground?

a) it shrinks to the size of a tennis ball

b) it swells to the size of a double-decker bus

c) it drifts off into space unchanged

Gray, of the British Antarctic Survey, says that data from the atmosphere about 5 km above Antarctica are helping to confirm findings by the U.N. Climate Panel that greenhouse gases are warming the planet.

She says that layer is warming three times faster than the global average during winter, or about 0.75 Celsius over 30 years, which is what computer models predict if man-made emissions are to blame for raising temperatures.

“It’s confirming the theory that warming is caused by greenhouse gases,” she said.

The balloons are let off around Antarctica and are giving clues both to weather and to the long-term climate.

 …and the answer to the question is “b” — after it swells to the size of a double decker bus because of a lack of pressure high up in the atmosphere it pops and falls to earth, along with the small measuring device that is then lost on the ice.

As a view out of your home it’s hard to match — a constantly changing vista of icebergs just outside the British Antarctic Survey’s Rothera research station.

Every day the winds and tides on the Antarctic Peninsula shift them around — some break up  abruptly with a loud splash while many simply slowly grind into ice cubes against the shore and disappear. I’ve tried to take a picture every day from the main balcony here (there’s a metal mast on the right hand side of each photo).

Walking along the shore here you can hear a bubbling as air in the ice melts out into the water. The old ice is the clearest — good for putting in cold drinks. Some form gravity-defying shapes such as arches or big holes — one in the bay a few days ago looked like a giant catamaran.

Icebergs cracking off glaciers in the distance can sound like an artillery shell exploding and big lumps falling into the sea send a wave across the bay. Seals lie on the beach, some of them snoring or nonchalantly scratching themselves — completely unbothered by the people passing by.

                                                                         Friday

Thursday

Wednesday

Tuesday

Monday

For anyone who thinks (like I did) that Antarctica is a bone-chilling freezer lashed by constant blizzards, a visit to the Antarctic Peninsula is a surprise.

As you can see from the picture, you can even play soccer at the British Rothera research station -- Stuart Mc Dill of Reuters TV (a skilled left winger) and I (unskilled) joined in a game last night and I have the grazes to prove it. Our team managed to win, 4-2, on the gravel pitch outside the plane hangar -- meteorologist Ali Price brilliantly knocked in three, even though he was wearing a pair of clunking hiking boots.

And last weekend, staff had an outdoor barbecue with steaks and a cooler for drinks made from snow scooped up by a bulldozer.

At Rothera, summer temperatures now are comparable to the winter in England, where the British Antarctic Survey has its headquarters in Cambridge. On "warm" days, when temperatures climb to about 7 Celsius, some in Antarctica staff wander around outside in tee-shirts and even shorts.

Temperatures today are 0.5 Celsius (32.9 Fahrenheit), not much cooler than 4.4 Celsius (39.9 F) at BAS headquarters.

In recent days, it has rained at least as often as it has snowed at Rothera.

Of course there has been rain here long  before anyone ever thought about global warming. But BAS glaciologist David Vaughan (who took the picture above) says that temperatures on the peninsula have risen by up to 3 Celsius (5.4 F) in the past 50 years -- making rains more likely.

And all of Antarctica is getting warmer, according to a report in this week's edition of the journal Nature. Until now, scientists have reckoned that the warming is limited to the Antarctic Peninsula but the U.S. study (for a story, click here) says that warming extends far wider across the frozen continent.

Staff at research bases, who relax by playing soccer, are trying to work out the risks of warming -- a melt of ice sheets would add to sea level rise and have unknown impacts on wildlife from penguins to tiny mosses that have adapted to freezing temperatures.

On a British Antarctic research station, engineer Andy Binney (pictured above at work) and plumber Adam Gerrard have what must be one of the shortest commutes in the world – 10 cm.

Here is a picture of Andy at work — installing boilers that will be partly powered by solar energy at the Rothera research station in Antarctica — and pointing to the wall behind which he sleeps. For a story about Antarctica shifting to renewable energies, click here.

Andy and Adam share the bedroom behind the 10 cm thick wall. If the boilers play up in the middle of the night, they will even be woken up by the noise.

At Rothera, run by the British Antarctic Survey, up to 100 base staff double up and share rooms with one other person in summertime. In winter, the base staff of about 20 get their own rooms. The base has a large canteen with great meals, Internet access, a weight training room, a library and a large room to relax in with beers in a fridge (maximum two drinks a day).

Andy and Adam joke that they might knock a hole in the wall to make it easier to get to work.

The project they are working on is part of a shift towards renewable energy in Antarctica — the United States, Australia, Japan, New Zealand and especially Belgium (with a base completely driven by wind and solar energy) — are doing the same. 

On the right is a picture of Andy inspecting a new batch of solar panels. 

Should all energy in Antarctica be renewable to help protect the environment — as well as cutting vast fuel bills? Or is that impractical because of the harsh climate?

Please tell us what you think.

You have to feel sorry for Australian aviator George Hubert Wilkins, one of the pioneers of flying in Antarctica who lived from 1888 to 1958 – and whose name is commemorated in an Antarctic Ice Shelf that is about to vanish into the ocean.

We landed near the narrowest point of the Wilkins Ice Shelf in a plane with a group of scientists from the British Antarctic Survey – who reckoned it was the first time anyone had visited within tens of kilometres (miles).

And it will probably be the last visit since the shelf is poised to collapse into the sea (for a story, click here).

Canadian pilot Steve King skimmed the Twin Otter plane in low over the ice and let the skis on the undercarriage slide over to test the surface for crevasses without committing to landing. We then swooped around and landed on the slushy ice — it’s scary enough landing on a runway in a small plane; here there was nothing but trackless white.

Glaciologist David Vaughan (pictured above) reckons the breakup could be days, weeks or months away – it is connected to Antarctica by a strip of ice that is just 500 metres wide at the narrowest point – in 1950 it was almost 100 kms wide. We landed a few km away from the narrowest point (shown in the picture on the right — the ice cliff at the front is about 20 metres high).

My colleague Stuart Mc Dill from Reuters TV and I then watched with alarm as Vaughan forced a long metal pole deep into the ice to set up a GPS monitoring device. ‘Um, David, are you sure that’s a good idea?’

Steve expertly got us off safely.

Wilkins is one of 10 ice shelves around the Antarctic Peninsula that have been retreating because of global warming — sediments beneath the glaciers show that the region has not been ice free for 10,000 years.

So goodbye Wilkins Ice Shelf — hello Wilkins Bay?

This won’t hurt, I promise….

Training for a couple of weeks’ stay in a British Antarctic Survey research base on the Antarctic Peninsula, Reuters Television reporter Stuart McDill and I have learnt emergency first aid ranging from how to wield a scalpel to ways to bind up a person’s neck injured in a plane crash.

We’ve also learnt the basics of how to sew up wounds, insert tubes into people who cannot breathe and even get the air out of a punctured lung — jabbing in a giant needle between the ribs just below the collar bone to release the pressure.

Most doctors spend years studying to be allowed to do any of these procedures. But safety is a top priority in Antarctica where things can very easily go wrong — the theory goes it’s better for people to have an inkling than no idea at all.

“We’re not expecting you to be a paramedic or a doctor,” says doctor Jason Coventry (pictured above, giving us a lesson). “Just help out until they can be brought back to base — I will fix them up.”

 Many people spend weeks on two-person expeditions – what Antarctic experts oddly call “in the field” – i.e. camping out on a freezing glacier, ice sheet or on a barren mountain in a tent.

That means everyone has to know a bit of everything — especially first aid.

The course has another side-effect — knowing that your companion might be your surgeon scares you into taking a lot of care.

A buzz of excitement went around the plane (left) when a scientist spotted the first mountains of Antarctica through the window on a flight from the southern tip of Chile.

Even veteran Antarctic visitors say there’s something special every time they see the continent — after all, Antarctica was only first spotted in 1820 — Fabian von Bellingshausen, a Estonian who was a captain in the Russian navy, usually gets the credit.

Stuart Mc Dill of Reuters Television and I flew in with about a dozen scientists and other staff to the Rothera Base, run by the British Antarctic Survey, on the Antarctic Peninsula in a tiny Dash-7 plane from the southern tip of Chile.

You expect to need lots of warm clothing but temperatures on arrival have been above freezing — they can reach a balmy 7 Celsius in summertime. There has even been a spot of rain. But scientists say rain has probably been falling here every now and then in summers long before anyone started thinking about global warming.

We’ll be staying at the base (the area is pictured above through the plane window) until Jan. 26 and will file regular blogs as well as stories and television reports after we complete compulsory training into everything from how to cross the runway (’look left, look right, look up in the sky’) to how to climb out of a crevasse.

And many visitors cherish the first sight of icebergs — like the blurry ones in the picture above.

On Antarctic cruise ships, people apparently crowd the decks to take pictures of an empty sea with a tiny dot of white on the horizon, even though they know they will soon be surrounded by them. I can understand the feeling.

Ice getting bigger hardly sounds like a sign of global warming but that’s apparently what is happening in the seas around Antarctica.

Leading climate scientists say that a tiny trend towards bigger ice in winter floating on the oceans around the frozen continent since the late 1970s — the maximum extent is around now, in September — is consistent with models of climate change that predict harsher winds and less warmer water at the surface.

It may even be that there’s more snow and rain falling onto the southern oceans because of climate change — that can raise the amount of fresh water on the surface and, hey presto, fresh water freezes at a higher temperature than salt water.

At Reuters News my colleagues and I often write stories about the shrinking of summer ice at the other end of the world, in the Arctic, as one of the clearest signs of global warming that is blamed by the U.N. Climate Panel on human use of fossil fuels.

In response to those stories, I often get e-mails from people sceptical about climate change who say that ice at the other end of the earth, around Antarctica, is expanding.

But it turns out that leading scientists at NASA, the British Antarctic Survey and Norway’s Nansen Center say the two things are not contradictory — the world reacts to greenhouse gases in different ways.

Antarctica is a gigantic frozen continent and winds sweep around it in the southern oceans, without drawing in much warmer air from further north. The Arctic is an open ocean ringed by continents, and more vulnerable to currents and winds blowing up from the south.

So you really can have your ice and melt it, depending on which pole you’re talking about.

What do you think?