Clean Air Sector Laboratory (CASlab) at Halley Research Station
Antarctica is a truly remote continent. There are no towns or cities on the continent, and it is thousands of miles to the nearest population centres. Because of this, the atmosphere over Antarctica is extremely clean and unpolluted. This gives us a chance to study what a clean atmosphere is like, find out what chemicals are in the air naturally and at what concentrations.
Ice cores are collected in Antarctica, and these give us information about how the Earths’s atmosphere and climate have changed over hundreds of thousands of years. This information is built up as snow falls and is compacted by more and more snow. Over long time periods, the snow is compressed to ice. We study the way that chemicals in the air (gases and particles) become integrated into the snow. By doing this, we learn about what some of the measurements from ice cores mean.
We carry out our research at a new laboratory at Halley, the Clean Air Sector Laboratory, or CASLab. The laboratory is located 1 km away from the rest of the station so that we don’t have to worry too much about contamination from the base. The CASLab is south of the base generators, and as the wind blows mainly in an east – west direction, it is quite unusual that pollution from the base reaches the laboratory. Scientists working at Halley visit the CASLab on a regular basis, but they have to walk or ski to get there, as, again, we don’t want pollution from vehicles anywhere near the laboratory.
The work that is done at the CASLab measures chemicals that are present at extremely low concentrations. Scientists who collect samples have to wear protective clothing to stop them contaminating the samples that they are taking; here is a scientist collecting snow that will be analysed to find out about the chemicals in it. Sometimes we do experiments on snow to see what chemicals is gives off – again, the scientists have to wear protective gloves. We also collect air into special flasks that are analysed to find out how much carbon dioxide is in the air. It’s really important not to breathe near the flasks when this work is being done.
Further information about the CASLab site: environmental conditions, technical information, data collection and science carried out here.