Logistics
Antarctica is the, coldest, driest, windiest, most moutainous and inhospitable land mass in the world. It is also the most remote continent and the only one that has not yet been completely mapped.
Summer in Antarctica is characterised by heavy snowfalls; objects left outside overnight usually have to be dug out from under snow drifts the next morning.
Icy blizzards lash the air during the freezing, permanently dark winters. Average Antarctic winter temperatures hover around -40°C, although -89°C has been recorded at the Russian base, Vostok. In fact, temperatures reach such low levels that materials change state. Mercury, for example, hardens into a solid metal; tin crumbles into pellets; ropes become as rigid as steel bars and steel splinters on impact. All moisture freezes instantly; tears freeze onto eyelashes and winter breath hangs in stalactites from moustaches. Without protection, human beings would freeze to death in minutes.
Completing even the simplest activities under these conditions is challenging. Conducting scientific research, which often involves the use of delicate and highly sophisticated equipment, is a massive logistical challenge.
A team of dedicated and highly trained personnel from the Department of Environment and Tourism meet this challenge by providing logistical support for South Africa's scientific missions to the Antarctic and sub-Antarctic islands.
Challenge 1: Transporting people, supplies and equipment
Antarctica lies approximately 4 500 kilometres from Cape Town across some of the wildest seas in the world. Seasonal ice surrounds the continent. Ice flows can crush the hulls of steel ships and sometimes ice breakers get trapped and crippled when steering gear is damaged.
The SA Agulhas is South Africa's only Antarctic research and supply vessel and works hard to complete her yearly schedule. In 2004, she is scheduled to sail twice to Marion Island, once to Tristan da Cunha and Gough Island, once to Neumeyer Station- the German Antarctic base -and once to SANAE IV. Over and above this schedule, SA Agulhas will undertake short research cruises off the coast of South Africa.
The ship has accommodation for 98 passengers and 40 crew, cargo holds, research laboratories and recreation areas. There is a meteorological station on board from which weather observations are conducted while the vessel is underway. SA Agulhas has winches and 10 000 meters of cabling for deep ocean sampling. There is a traveling deck crane for moving cargo from the holds and a large crane mounted on the bow which is capable of lifting a 25 ton tractor 20 meters onto the ice shelf. There is a large hangar and flight deck that accommodate two helicopters.
Challenge 2: Offloading
In order to supply SANAE IV, cargo needs to be hoisted from the SA Agulhas onto the ice shelf. At Blaskimen Bukta (the Norwegian word for 'bay'), the ice shelf towers up to 25 meters above the ship's decks and has to be lowered by cutting a ramp using bulldozers, an extremely dangerous operation.
The approach to Blaskimen ice shelf is risky for the SA Agulhas. Ice does not crack evenly and ice that juts into the ocean below the surface of the water could damage or even sink the ship. The shelf is extremely unstable and if a crack appears, a new ramp needs to be built at a safer site.
Although helicopters can be used to offload cargo, this is an expensive, cumbersome and time consuming option and an alternative has been sought for some time.
The closest stable ice shelf to SANAE IV is at the German base Neumeyer, 300km across an ice plateau. South Africa and Germany have recently co operated to establish a route that links the two bases. German glaciologists studied satellite images in order to predict which routes were crevasse free. Their recommendation was confirmed by flying the route by helicopter. Then, the SANAE IV field manager and his assistant traversed the route on motorised snowmobiles (skidoos) to determine which of the routes had the gentlest profile. They plotted their preferred route on a GPS and radio senders were positioned to establish communications. Snow tractors pulling full loads have used the route and confirmed that it is suitable for heavy vehicles.
The opening of the new route between SANAE IV and Neumeyer has proved to be a success and it promises to be mutually beneficial to both the German and South African Antarctic expeditions.
Challenge 3: Communication
Communication is an important part of safety routines at SANAE IV. Anyone who leaves the base is required to check in at regular intervals to confirm their status. Satellite technology facilitates communication by telephone, e-mail and fax, both between bases in Antarctica and between SANAE IV and South Africa. Very high frequency (VHF) radios are most commonly used at SANAE IV because they are inexpensive and reliable. Radio transmitters have been placed on high points around the base to facilitate communication by VHF radio. Where radio senders cannot be placed, high frequency (HF) radio is used.
In Antarctica, cooperation is essential, but communication has the potential to saves lives.
Challenge 4: Food
Human beings require large quantities of fuel in order to survive the icy conditions in Antarctica. SANAE IV and the bases on Marion and Gough islands are stocked with sufficient food supplies to last 18 months, in case of emergencies.
The annual shopping list for Antarctic expeditions reads like Gulliver's first meal on Lulliput. Almost five tons of meat, 142 kilograms of oven chips and 30 kilograms of biltong flavored cheese spread are transported SANAE IV each year.
The team doctor is responsible for managing the food stores and for ensuring that the team's diet is well balanced and nutritious. Freezers are used to keep temperatures stable rather than low.
Surprisingly, fresh water is a difficult resource to access in the Antarctic. All available water is locked up as ice and dehydration is a serious threat. At SANAE IV, ice is melted by heaping it onto a steel grid which is positioned over heating elements, using a bulldozer. This is one of the only outdoor activities that continues throughout the winter. Water pipes leading from the smelter into the base need to be heated to stop them from freezing.
Challenge 5: Ice transport
Modern vehicles have changed the way Antarctica is traversed. South African scientists and support personnel make use of a fleet of 32 "skidoos", small but powerful snow motorbikes that are quick and efficient over short distances. For heavy work, they use five snow tractors and six snow bulldozers; three are fitted with cranes and blades for pushing ice and three are fitted with winches
and buckets for lifting cargo and equipment. A caboose, which is towed on sleds like a caravan, provides mobile accommodation.
All vehicles at SANAE IV use polar diesel from which the lubricating organic wax has been removed and replaced with a synthetic mixture that includes Teflon. Synthetic replacements ensure that lubricants and fuels stay liquid at temperatures as low as -55°C. SANAE IV uses 450 000 litres of polar diesel per year. Over half of this is used for meeting the heating and power requirements of the SANAE IV base.
Challenge 6: Waste
With consumption comes waste and the logistics team is required to dispose of waste in an environmentally responsible manner. No effort is spared to ensure that environmental impact is minimal. A good example of environmental responsibility is provided by the fuel pumping operation.
Fuel is pumped from the SA Agulhas into holding tanks, a process that can take up to 18 hours, depending on the height of the ice shelf. In order to detect leaks in the fuel pipes, air is pumped through the pipes. Holes are repaired, but if any fuel drips from the pipe, pumping stops and the spilt drops are mopped up. If over 20 liters are spilt, an incident report is filled out and submitted to the Antarctic Committee on Environmental Protection. After pumping, air is blown through the pipes a second time to remove residual fuel. The pipes are coiled carefully so that any stray drops may be captured.
Startup emissions from vehicles have recently been cut down by fitting heaters which warm the engines up to 45°C before starting. This process also extends engine life. Solid waste is separated and transported back to South Africa.
Sewage is processed in a sealed unit by genetically improved and patented bacteria, and an odourless, colourless water is emitted as an end product. Concentrated sewage sludge is containerised and returned to South Africa.
All bases in the Antarctic are obliged to perform environmental audits on an annual basis and Treaty members are required to inspect each other's bases -a testimony to the cooperative spirit of the Antarctic Treaty.
The inspection includes detailed interviews with randomly selected personnel to determine whether people are informed about and conform to strict environmental standards. Although South Africa consistently receives high marks for environmental compliance, there is an ongoing effort to approach zero impact and maintain a pristine environment.
Despite the enormous logistical challenges involved, South Africa's Antarctic support team is continuously experimenting and striving to improve efficiency and cut down on costs, while making life more comfortable for the expedition members. This is aided by international cooperation and by keeping a close watch on technological advances. |
