Tuesday, 21 October 2008

The Last great expedition


Landing at the head of the Robert Scott Glacier about 100 km from the South Pole. Photo: Bob McKerrow
When I landed at the Robert Scott Glacier in 1970, I recall thinking, "what is under the thousands of feet ice I am standing on."
Thirty-eight years later I have an answer. At this very moment, perhaps the last great Antarctic expedition - to find an explanation for why there is a great mountain range buried under the White Continent.

The Gamburtsevs match the Alps in scale but no-one has ever seen them because they are covered by up to 4km of ice.

Geologists struggle to understand how such a massif could have formed and persisted in the middle of Antarctica.

Now, an international team is setting out on a deep-field survey to try to get some answers.

The group comprises scientists, engineers, pilots and support staff from the UK, the US, Germany, Australia, China and Japan. It's rather like being an archaeologist and opening up a tomb in a pyramid and finding an astronaut sitting inside. It shouldn't be there




Dr Robin Bell, Lamont-Doherty Earth Observatory

The ambitious nature of the project - working in Antarctica's far interior - has required an exceptional level of co-ordination and co-operation.

"You can almost think about it as exploring another planet - but on Earth," said Dr Fausto Ferraccioli from the British Antarctic Survey.

"This region is a complete enigma. It's in the middle of the continent. Most mountain ranges are on the edges of continents, and we really can't understand what these mountains are doing in the centre."

The AGAP (Antarctica's Gamburtsev Province) project will establish two camps from where the team will map the subglacial range using surface and airborne instruments.

EXPLORING THE SUBGLACIAL GAMBURTSEV MOUNTAINS

1. Aircraft will use radar to detect ice thickness and layering, and to map the shape of the deeply buried bedrock
2. The planes will also conduct gravity and magnetic surveys to glean more information about the mountains' structure
3. By listeni
ng to seismic waves passing through the range, scientists can probe rock properties deep in the Earth.

Dr Fausto Ferraccioli describes the equipment onboard the aircraft

The Gamburtsevs were discovered by a Soviet team making a traverse across the ice in the late 1950s. The rocky prominence was totally unexpected; scientists thought the interior of the continent would be relatively flat.

"There are two easy ways to make mountains," explained Dr Robin Bell, from the Lamont-Doherty Earth Observatory, who is a lead US researcher on the expedition.

"One is colliding continents, but after they collide they tend to erode; and the last collision was 500-million-plus years ago. They shouldn't be there.


Dr Robin Bell says the team will perform an x-ray of the ice sheet
"The other way is a hotspot, [with volcanoes punching through the crust] like in Hawaii; but there's no good evidence for underneath the ice sheet being that hot.

"I like to say it's rather like being an archaeologist and opening up a tomb in a pyramid and finding an astronaut sitting inside. It shouldn't be there."

The mountains are believed to have been a key nucleation point for the vast East Antarctic Ice Sheet.

It is thought that as Earth's climate cooled just over 30 million years ago, the snows that fell on the mountains produced mighty glaciers, which then merged to form one giant spreading ice-mass.

A better understanding of these events could give clues as to how Antarctica might evolve in the coming centuries if, as expected, the Earth continues its current warming trend.

The aerogeophysical survey of Antarctica's Gamburtsev Province (AGAP) is a flagship endeavour of International Polar Year - the global science community's concerted push to try to answer the big questions about the Earth's northern and southern extremes.

The challenging nature of the expedition has required that expertise be drawn from across polar community. Supplying such remote camps is a major logistical exercise; working in them - at temperatures 30-40 degrees below zero Celsius - is bound to be physically demanding.

Two survey aircraft will sweep back and forth across the ice to map the shape of the mountains. The planes will be equipped with ice-penetrating radar and instruments to measure the local gravitational and magnetic fields.
Air bubbles trapped in old ices record environmental conditions

Information on the deeper structure of the Gamburtsevs will come from a network of seismometers that will listen to earthquake signals passing through the rock from the other side of the globe.

"We'll map everything from the detailed ripples on the surface of the ice sheet down to the temperature structure hundreds of kilometres in the Earth, so we'll have everything from the layering in the ice to what the nature of the rocks are," said Dr Bell.

Another important aim of the project is to find a place to drill for ancient ices. By examining bubbles of air trapped in compacted snow, it is possible for researchers to glean details about past environmental conditions.

Not only can they see concentrations of carbon dioxide and methane - the two principal human-produced gases now blamed for global warming - but they can also gauge past temperatures from the samples.

Somewhere in the Gamburtsev region there could be a location were it is possible to drill down to ices that are more than a million years old. This is at least 200,000 years older than the most ancient ices currently in the possession of scientists.

The expedition will take some two-and-a-half months to complete.

So 38 years on, this aging Antarctic explorer will have his curiousity satisfied when the results of th eexpedition are made public.

Below are some photos I took in the good old days when we travelled by dogs.



Shackleton's Hut at Cape Royds.

Scott's Hut at Cape Evans.

Thanks to Jonathan Amos for permission to use some of his data.

10 comments:

Jamie said...

Hey Bob,

6.30 in the morning in China just preparing to catch another bus and your posting puts me in a good frame of mind.

Not so much the mystery of the mountain range (there must be some hard rock under there and nature has so many natural wonders and exceptions I don't understand), but more your continued interest and following of the area.

I have a similar interest in the subantarctic islands which I helped in managing for a short time and visited twice. I still occasionallly wake up thinking about the beauty of the Royal Albatross, the synchronised aerial displays of the Mollymawks and all the other wildlife and history that these islands contain. I better start blogging about it!!

ps: there is no last great expedition ;-)!

Bob McKerrow said...

Jamie, you should be blogging about your travels in China, Indonesia and the sub-Antarctic.

You are right, there is no last great expedition, for every journey hss the potential to be a great one. I would enjoy to read more of your travels.

Best wishes. Bob

Marja said...

Hi Bob How is life? Exciting another mystery to be solved. It is quite fascinating. I love discoveries (especially ancient cultural ones though)
Nice pictures of the huskies. They look exactly like Akela, the Huskie we got at work. He sleeps most of the time. They don't like taking him for a walk because he chases other dogs.
Oh I made a new banner for my blog I like playing around with it. See what you think
Ka kite ano, marja

Bob McKerrow said...

Dear Marja

I will certainly have a look at your new design on your blog. Huskies are wonderful dogs and love to work and fight. Yes, this new discovery in Antarctica is fascinating. I love these mysteries being uncovered.

Take care

Bob

Jamie said...

Hey Bob,

I have a bit of a blog, not much wisdom on there though. Just a few nice photos, some thoughts and a few travel stories to keep the rest of the family involved.

pennyandjamie.blogspot.com

Ruahines said...

Kia ora Bob,
I shall look forward to the progress of this undertaking. I have never considered the mountains being there in any way unusual to reading your post. These would be mountains then that Shackleton, Scott, and Amundson battled with as well in a way?
Have just returned from 5 nights in the Ruahines including a whole day sitting on a porch hut watching an uncrossable flooded river roll by. It was great. Cheers Bob, have a great day.
Rangimarie,
Robb

Bob McKerrow said...

Hi Jamie

I look forward to reading your blog and learning more about your journey in China.

I agree, there is no last great expedition, as you can make every journey a great one.

Cheers

Bob

Bob McKerrow said...

Kia Ora Robb

It must have been awe inspiring being trapped by a river. Pleased you were back in your old stamping grounds. I have been on the road for ten days from Aceh to Bangkok.

Saw a lot of ground and a lot of people. Will write a note tomorrow.

Cheers

Bob

PATERIKA HENGREAVES, Poet Laureate said...

Kia ora Bob

This is indeed a marvellous write. Now I know that you are among the many seabees that have left footprints on the "White Continent". However, I'm befuddled as to why you assigned to your article the title, "The Last great expedition". This is so, from the standpoint that we are celebrating the Fourth International Polar Year 2007-2008 with laudable goals of advancing science, social science, humanities and education in and about earth's cold environments at the extreme "ends" of the earth and by extension, Antarctica remains a focal point in mankind's collective consciousness for researching an implementing sources of renewable energy and much more.

Thank you very much for this article. It has given me the inspiration to write an Acrostic poem rhyming abcdcbeff a tribute to Scott Base's fifty-first anniversary in the series of poems I shall be writing in recognition of the Fourth International Polar Year (IPY).

Cheers
Paterika

Bob McKerrow said...

Dear Paterika

A careless moment has its consequences. You are the second person to make the same comment. It was a bad choice of title. Most expeditions are great in some sense, but the the "Last' is robbing others of their chance of discovery.

It's 5.30 am, and I leave soon on a three hour drive for West Jave where 3,000 volunteers from Red Cross societies around the world are gathering for a camp to exchange experiences and ideas. I love being with young people and being able to share stories.

My 13 months in Antarctica at the age of 21 made a huge impression on me, but I chose not to go back. I knew it would never be the same. Trying to recapture memories can be disappointing.

I look forward to your poem on Antarctica. I enjoy your poetry very much.

Warm regards

Bob