Dome A is the coldest place on earth. During Winter temperatures fall to below minus 90 degrees centigrade. And that's before you add in wind chill.
Scattered across Antarctica are hundreds of weather stations. They're usually placed in position during the relatively balmy summer, a time when the sun shines for much of the day and the station's batteries can be recharged for the darkness of the winter season.
Dome A, however, presents a problem says Jon Reeve, science and technology support manager for the Australian Antarctic Division (AAD). The weather station that will be dropped there by a Chinese expedition traversing the continent, has to operate in conditions that are often more hostile than space. "Batteries are a problem," says Reeve. "Many of the other [weather stations] use lead-acid batteries with very concentrated electrolytes that won't freeze. But in the sort of temperatures that we'll have at Dome A, getting batteries to work at all presents a problem."
That's because batteries become less efficient as the temperature falls. And it's not as if the team can simply pop back out to the station if something fails. It has to work, and has to work reliably for a long time. "It's too inhospitable, and too expensive to go out on missions to retrieve technology that fails," Reeve says. "So the solution not only has to be effective, it has to be efficient."
The weather stations illustrate the challenges faced by Antarctic-bound technology and the teams that have to support it. Reliability and simplicity are the keys to success.
The Australian Antarctic Division maintains research and development labs in Tasmania for the express purpose of building, testing and designing equipment for hostile environments. "Our role is to adapt technology, redesign technology or often to design technology from scratch," says Reeve. "We've developed extensive knowledge of what does, and doesn't work."
To assist them in this task they use an environment chamber capable of lowering the temperature to minus 80 degrees Celsius. "Of course, we can't replicate the windchill," says Reeve, a veteran of an 18-month posting to the frozen continent.
While much of the design is done in house, manufacturing is a collaborative affair, with much being outsourced to other Australian-based industries. Often times, the AAD's innovations are simple, but can save lots of time and money.
"There was a net that we used to catch krill and other small organisms," Reeve says. "We'd find the krill, but could only do one run. The design of the net was refined so that the first run could be stored in a chamber, and then the net reset for another run."
The upshot? More effective science because of a larger sample size, and a massive increase in efficiency because the net could be reset in situ.
Traditional technologies, such as PCs, laptops and servers, aren't the challenge one would think. Why? Because these devices are almost always located at the base station, or in another temperature controlled environment. Ruggedisation isn't really an issue unless they're being taken out into the field. Even then, they're likely to be left in the vehicle than taken outside.
But what about the Dome A conundrum? It was solved through the simple expedience of burying the batteries. "The temperature is much more stable underground, around minus 60 all year," Reeves says. Problem solved.