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| Pictures of Antarctica |
Antarctic
Bases and Buildings - The Evolution of the Modern Base
2 - Building on an Ice-Shelf
1- Traditional Land-based | 2 - Halley Bay - UK | 3 - South Pole (USA) | 4 - Princess Elisabeth (Belgium)
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Dogs and Men
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 Current weather conditions at Halley Halley VI was due to be fully occupied during 2009, though for winter 2011, Halley V is still in use. The end of the "Halley Stare" - psychological benefits Living underground (under-ice really) meant an odd sort of life, especially in the winter months. In order to see the outside world it was necessary to climb up the access shaft, dress appropriately (lots of clothes) and then get outside where it was dark and fairly featureless - not a lot of incentive to make the effort in other words. Ex Halley personnel could be fairly easily spotted at other bases or onboard ship on their way north by the "Halley Stare" sometimes known as the "20 foot stare in a 10 foot room". They would often be seen standing by the window looking out for long periods. The installation of above ground elevated bases with windows has more benefits than just avoiding snow drifts... |
Case 2
- Halley Bay (UK) Brunt Ice Shelf While coastal regions in Antarctica experience the melting of snow and ice in the summer months, regions that are further inland often experience no melting at all and so all of the snow and ice that falls accumulates continuously. Bases that are built in such places therefore become slowly buried in the snow and ice. Halley Station is located on the Brunt Ice Shelf at 75°35'S, 26°34'W. Halley Statistics
Elevation 30meters, (98 feet) Halley I, II, III and IV Base design - huts on snow surface, became buried over time due to snow build up This accumulation of snow was anticipated when such bases were built, and in the case of the UK base at Halley Bay first built in 1956, the construction was particularly strong to take the weight of the accumulating snow and ice which had almost completely covered the original (conventional style) buildings at the end of the first year. The snowfall at Halley accumulates at the rate of around 1.5m (5ft) per year. Life below "ground" Access was by a regularly dug-out slope down to the doors until it became impossible to keep these clear. At this point access became via a hatch in the roof. As snow and ice build up continued, so the height of the access hatch increased to reach the surface. Eventually in 1967 after 11 years this first base was abandoned due to a difficulty of access but more importantly as the buildings were being crushed. Parts of the base were 30-40 feet under the surface level at this time. A second base was built nearby this time with a strong steel frame to take the weight. Again it was slowly buried and six years later this time had to be replaced again. This time for Halley III strong corrugated steel tubing (Armco) was built as a protector for the wooden base buildings that went inside them, but once again by the time it had been buried 40 feet it was time to rebuild. Try try again A similar design was chosen for Halley IV, though this time of insulated plywood panels time making two large tubes interconnected in a H-shape that would insulate the huts they contained better than the metal had done which gave problems of its own when snow and ice touching the tube in the warmer parts of the base caused melting. This lasted four years and then in 1989 a different approach was attempted. And with a single bound, it was free! - Halley V Base design - supported on jackable legs above the snow surface Rather than a base that would be buried and inevitably lead to its destruction and waste, a base was planned that would be on the surface and stay on the surface. It would be held off the ice surface by legs which would be "jackable" that is they could be jacked up slowly by operating a mechanism similar to a car jack. In this way the base could be kept above the snow as the level grew higher beneath it, all that would be lost would be the metal legs left behind in the ice. Similar solutions had been used successfully on a smaller scale before with cabooses (essentially kitted out shipping containers) being treated this way at Halley. This base, the 5th one at Halley Bay so named "Halley V" was built in 1989. It is the most successful base in that it has lasted 20 years and has led to less frequent disruption from re-builds. In fact it could have a lifespan longer than this, the reason it is now being replaced is that as it is situated on a moving ice-shelf. It is getting closer to the sea and there is a danger that a large ice break-out could leave it and it's base compliment of scientists and support staff floating on an ice berg. Worse still the station could be situated on a future break-up zone itself and suffer a disastrous loss of the base and possibly of life. The next generation - Halley VI Base design - supported on jackable legs above the snow surface, legs placed on skis so that the base can be moved Work on Halley VI therefore was started in the Austral summer of 2007-2008 with an award winning new design that has the jackable legs of Halley V with the added flexibility of each leg being on a ski. In this case, when the base moves too close to the sea with the drifting ice-shelf, the modules can be towed further inland by tractors. In addition to this, the "pods" are more flexible in function than previous bases being able to be converted to sleeping accommodation or scientific labs as required. A further advantage of the old base (Halley V) becomes evident at this point. Previous bases were buried in the ice and flowed with the ice shelf to the coast where they would eventually fall off the end into the sea. Halley V will be broken down and removed from Antarctica leaving hardly any trace of it's presence. |
