Polar Passport

Landing Bluff

I'm extra happy this week - I've successfully finished all the planned field work. We had to wait a week for clear weather, but on Sunday afternoon we left Davis with two helicopters, heading for Landing Bluff, about 200 km to the southwest.

We needed two helicopters for safety - it's too far to quickly send help from Davis if something went wrong - but my equipment could easily fit into one, so there were a few extra seats. That meant we could take some passengers - three 'tradies' who've been working at Davis station all summer, and deserved a chance to see some more antarctic scenery.

Around Davis, the sea ice has been gone for several weeks, but further along the coast it is more protected in sheltered bays and among the islands and floating glaciers.

The work was fairly simple, and went as planned: changing batteries and checking the instruments at another GPS installation. Landing Bluff is a small but beautiful hill, with a lovely view.

In the picture you can see the frozen sea below and the glaciers in the distance. The equipment is right on top of the hill, and at the right is one of the 'Squirrel' helicopters. There's a Russian summer base nearby, and you can also see where they've left messages written on the ground with small white stones.

Flying back to Davis the weather was cloudy over the coast, but clear out over the sea to the west. The sun was shining on the calm water studded with icebergs, and virga from the dark clouds over us was silhouetted against the light background.

In three weeks, the 'Aurora Australis' will return to Davis to take us back to Hobart. I have a few jobs to do before then: organise and process some GPS data, pack and consign my cargo, and help out around the station wherever I can. I also hope to get out for a bit of recreational walking in the Vestfold Hills.

I'll have plenty of access to the internet while I'm on station, so if you have questions about the blog, now is the time to ask! To ask a question, just click the "comments" link below.

Back at base,

Dan

Enderby Land

I spent the last few days far from here; camping at Mt Riiser-Larsen, in Enderby Land, about 1000 km west of Davis.

We flew there in the CASA planes; after leaving Davis we headed across the sea. It was wonderful to look down on the patterns of ice in the water, made by winds and currents.

After two and a half hours of flying, we arrived at another Australian base, Mawson, to refuel and pick up a couple of passengers. It's a beautiful place: the station is built on a rock perched between the ice sheet and the sea, and the plane landed near the Framnes Mountains, jagged ridges of rock poking through the ice.

From there, we flew west for two more hours, over hundreds of kilometres of smooth ice sheet, enormous glaciers flowing into the frozen sea, barren islands of rock surrounded by ice or ocean, and sharp mountain ranges extending to the horizon. Antarctica is wild and beautiful almost everywhere you look at it, but from an aeroplane you can appreciate how enormous and bleak it is...magnificent!

We landed on a frozen lake, unloaded our equipment, and looked for a place to camp. One of the CASA's stayed with us, while the other flew further along the coast to the Japanese station, Syowa, where one of our colleagues had some work to do. We used a sled to carry our tents and food to the shore of the lake, while the pilots, Dan (not me!) and Troy, tied the plane to the ice, in case there was a storm while we were there. We also had an AAD field officer with us, Mick from Mawson.

We put up our tents on the snow not far from the plane, with a great view of Mt Riiser-Larsen on the other side of the lake, and made a place among the rocks to use as a kitchen - usually it's not too cold to eat outside, and the view is much nicer than inside a tent!

Like at the Bunger Hills, our job here was to install a GPS receiver, to measure how the land of Antarctica is moving. Nick and I did that together over the next two days.

While we were working, the other guys did a couple of long walks, and came back in the evening to cook dinner.

Cooking can take a long time in Antarctica, when you have to melt you water from snow, and cook on a small camping stove, so having Mick, Dan and Troy to help us meant that Nick and I could work several more hours each day. It makes a big difference to how much we can do - thanks guys!

The GPS system has an antenna which is bolted to the rock, and protected by a plastic dome so it doesn't get covered in snow in the winter. Solar panels provide the electricity, and all the batteries and instruments are inside an insulated box, to keep warm. Every day, a computer in the box uses a satellite telephone to send the GPS data back to Australia. It was working perfectly when we left... I hope it stays that way for the next few years!

Yesterday, our work was finished and we flew all the way back to Davis, stopping again at Mawson to drop Mick back there and refuel the plane. Late yesterday evening we were back at base, heated up leftovers from dinner, and had a good shower! It seems like a very short trip, but we worked hard all the time, and did everything we planned to.

This summer's field work is going well!

Already preparing for the next field trip,

Dan

The Bunger Hills

Finally, we've started our work!

Last week I was in the Bunger Hills, an area of rocky hills not covered by snow or ice, about 20 km across. It's one of the largest ice-free areas in Antarctica, so it's called an 'oasis', where there are some lakes and a few mosses growing on land. It's between two of Australia's stations: about 1000 km east of Davis, and 500 km west of Casey. I'll try to post a map soon, with all these places. Not many people visit there, but the AAD has four small fibreglass huts, which they call "Edgeworth David Base", where we stayed.

We flew there in a CASA aircraft, with all our gear and several hundred kilograms of science equipment, and landed on a frozen lake in front of the base.

I call it a lake, because it's fresh water underneath the ice, but one side of the lake is a glacier, which is floating on the sea. The glacier goes up and down with the tide, and so does the lake, and the ice on top. So to walk from the plane to the huts on land, we had to cross the 'tide crack', where the ice moves against the land. Not difficult or dangerous, but there are some pools of water where you could get your feet wet. You can see it in the picture below.

At the left of this photo you can see the frozen lake, and the CASA plane that took us to the Bunger Hills. Between the plane and the land, you can see the 'tide crack' On land, you can see the four small huts (called 'apples') of Edgeworth David Base, and then on the right is the GPS equipment that Nick and I installed. You can see the solar panels, and the wind generator, which we hope will power the instrument all through winter.

Photo credit: Dan Colbourne (CASA pilot).

There were five of us working there: Nick and I were installing surveying equipment, Pat and Krystyna were collecting moss samples, and Mel is a "Field Training Officer" who works for the AAD, and was there to make sure everything was done safely.

Ill be working with Nick for the next couple of months. He's from Geoscience Australia, and I'm from the ANU, but we do similar work, so it makes sense to cooperate for the field work. In the Bunger Hills we installed an instrument for GA, and the next place will be for ANU. Nick is also keeping a blog about his trip to Antarctica.

We installed a GPS receiver, which we hope will operate there continuously, 24 hours a day, 365 days a year, for several years.

Like the GPS some people use bushwalking, or in their car, this one uses signals from satellites to measure its position on the ground. But it's more precise than normal GPS's: with a normal one, you can get your location accurate to about 10 m. That's good enough for walking or driving, but we need better accuracy: this one can give us the location to within 1 cm!

With that precision, we can study the movement of the Earth's tectonic plates, and also how Antarctica moves because of changes in the amount of ice there. That is my main interest here, and I'll write more about it later.

The GPS receiver is powered by six big batteries (like car batteries, but special ones for the cold), which are charged by solar panels in the summer, and a wind generator in the winter (when there isn't any Sun). It sends the measurements back to Australia by Iridium satellite telephone.

We celebrated Christmas while we were there: we had a few decorations in the hut, cooked a huge meal, and opened presents from home. A Perfect Antarctic Christmas!

Merry Christmas,

Dan