Archive for the 'Science' Category

Science Pack Up

The Science team have been extremely busy over the last few months packing up a lot of the science equipment in preparation for the arrival of the ship. To make room for the construction team and their supplies some of the science that has been happening at Halley must be interrupted for the duration of the build.

The geologger lab before and after Electronics lab before and after
The geologger lab, before and after it is converted into a conference room. One of our electronics labs had to be merged with another one to make space for the construction team.

Some of the experiments will be run at other locations before returning to refurbished facilities in two years time. Other experiments will be returned to Cambridge for upgrades and development work, while our most critical long term monitoring will continue at Halley throughout the construction project. This has meant a certain amount of relocation, with all our remaining experiments being crammed into a lot less space. Continuing experiments include Dobson Ozone measurements, the Search Coil Magnetometer, Ground ozone measurements, Bomem optical studies, Very Low Frequency radio studies, meteorology, daily weather balloon launches, air and snow sampling and more.

Ongoing science Boxes in a container
Ongoing science in the Dobson room and the new meteorology office. Boxes start to fill one of the outgoing shipping containers.

Since packing back in September, the science team have packaged and consigned approximately 6000kg of cargo in over 100 boxes. With the end now near I suspect none of them will miss the sight of bubble wrap or packing tape for some time!

An empty office Empty shelves ready to be filled
The Simpson Office is emptied to make room for supplies that need to be kept warm. Empty shelves ready to receive cargo during relief.
Link | Posted by Simon in Science, Construction on December 21st, 2007

The Season Begins

The start of the first construction season has now well and truly begun, in fact so much so that we haven’t had a chance to update the website for quite a while!

The Halley VI trial module is now complete, with the first module successfully assembled in Cape Town last month and now is disassembled ready to go onto the ship. The process of constructing the trial module identified some difficulties, which now resolved should help speed up progress at Halley when each module is finally put together.

A completed module in Cape Town

A completed module in Cape Town. It is without skis and pictured at its lowest setting, on site it will stand considerably higher off the snow.

The Ernest Shackleton has just finished loading cargo in Cape Town and set sail a few days ago heading for Halley. She is due to arrive before Christmas, but first has to work her way through a great deal of ice to reach the Halley coast. The Amderma, our huge cargo ship is now loading cargo in Cape Town, and will follow the Shackleton south in a few days time. You can see the progress of both ships, along with the Polar Stern (a German research vessel) on the chart below:

A tracking map showing the progress of the ships.

A tracking map showing the progress of the ships. The Ernest Shackleton is shown in green, the Amderma is in black. The red areas show regions currently covered in sea ice.

Although the most visible work will occur at the Halley V site this season (the building of the modules), there will be a team working out at the Halley VI site laying power and data cables and digging in the foundations for the masts and towers. So they know exactly where to put them we have been out to the Halley VI site to survey some of the key locations. Karl, the Project Manager and Steve the Building Supervisor have spent several days out at Halley VI precisely marking out the site. With a background in Civil Engineering, it seems an opportunity for Karl to get out the office and back behind the sights of a theodolite was not to be missed!

Karl surveying at the Halley VI site

Karl surveying at the Halley VI site

Another key task was to mark out the boundary of the Halley VI Clean Air Sector. This region will contain the new Clean Air Laboratory, so it is vitally important that we ensure the pristine snow is not polluted during construction. To avoid this we have set up a 1km exclusion zone around the site of the new lab, with a single access road and tight restrictions in place during construction.

Flags marking the boundary of the Clean Air Sector

Flags and a signpost marking the boundary of the Clean Air Sector

Link | Posted by Simon in Science, Construction on December 9th, 2007

Summer at Halley

The BAS ship RRS Ernest Shackleton is now heading north after another busy summer season at Halley - the last before the beginning of the construction of Halley VI next year. For the Halley VI team this was our last chance to complete testing and start preparing the station for construction - and there was a lot to do.

Vehicle testing

Martin’s new vehicle fleet were quick to get stuck into the job of moving cargo from the ship to the station. Soon after they had been offloaded they took over the job of relief from the snocat fleet. We will be relying on these huge vehicles next season to move all the construction materials from the ship to the station, so we were pleased to see they were up to the task. The Challengers where able to pull up to 48 tonnes at speeds of 20km/h, compared to 10 tonnes at 10km/h for a snocat. The John Deere tractors proved invaluable as multipurposes vehicles, pulling cargo, lifting containers and palettes of cargo or grooming roadways.

Vehicles at work
Top left: John Deere is craned off the ship during relief… Top right: …and immediately put to work. Bottom: Challenger pulls three sledges of fuel drums to the station.

With relief out of the way we were able to turn our attention to the summer work programme. In order to reduce travel times next season the garage and summer accommodation buildings were to be moved closer to the rest of the site. With each building weighing 60 tonnes, the new vehicles again proved useful, but even this was just a warm up - the big test was yet to come.

Garage being towed
The Challengers preparing to move the garage to its new home.

The new station relies on a series of ski based modules, each of which can be towed across the ice shelf. To ease construction the new station will actually be built at the site of Halley V, then towed 15km away to its final destination. Of course we need to be sure that the vehicles will be capable of towing the structures we are going to build, and with modules weighing up to 140 tonnes, that’s no small feat.

The Loaded Test Sledge
Loading vehicles onto the test sledge to bring it up to weight.

To be sure they were up to the job we built a second steel sledge, to join to the smaller one that was built last year for the initial vehicle testing. These sledges have the same sort of skis as the modules will, so they represent a similar challenge to move. The test sledges were loaded with everything we could find to get them up to weight then towed over a variety of surfaces (fresh snow, groomed snow, heavily compacted snow). Once again the new vehicles proved themselves to be up to the task - at their peak they were pulling a load of 155 tonnes!

Pulling the Test Sledge
Pulling the test sledge.

Snow Models

On a completely different scale, 1:50 models of the current Laws platform, along with three of the Halley VI modules were brought in this year to study the effect of snow accumulation on the new base. The data will be used to complement data from numerical models and will help us to understand the snow management that will be required at Halley VI. The model of the Laws platform showed us that the wind tails produced by the small models accurately represent what actually happens on station. The Halley VI models suggested that the more aerodynamic shape of the new buildings will lead to smaller wind tails than are produced at Halley V. A second positive benefit is that the legs of the new buildings appear to remain clear of snow, which should make the jacking procedure more straightforward.

Laws Scale Model Halley VI Scale Model
Left: Scale model of the Laws Platform, with the real thing in the background. The wooden stakes were used to measure the amount of accumulation at various distances from the model. Right: Wind tails produced by the Halley VI modules. The building shape is designed to keep the legs clear of snow.

Site Planning

With the Halley V site due to become a construction site next year we spent some time marking out the areas where the building work would take place, as well as where the completed modules would be parked up for the winter once they were finished. At the same time the Halley VI site was also being marked out. Next year the foundations for the masts need to be placed so the locations of many of the buildings needed to be calculated.

This gave us an opportunity to visit the site that will become Halley VI over the next few years. At present it is flat ice like the rest of the ice shelf, with the only distinguishing feature being an automatic weather station that is collecting data on the new site.

Halley VI Team at the Halley VI site
The Halley VI Project Team visit the Halley VI site. Left to right: Paul Cousens, Martin Bell, Simon Coggins.

Finally there was a great deal of planning and preparation work to be done - removing unnecessary stock and working out exactly what would happen to all the equipment that is currently on base. Rod Downie was visiting from the Environment Division to look at the amount of waste that would be generated by the removal of Halley V, so that we can look into recycling as much of it as possible.

Link | Posted by Simon in Vehicles, Science, Environmental on March 2nd, 2007