The Air Chemistry Observatory of Neumayer
It is obvious that the atmosphere above Antarctica is the cleanest part of the Earth's troposphere and can be employed as a large clean air laboratory to study natural conditions comparable to atmospheric processes prevailed elsewhere in preindustrial times. With the exception of some rocky coastal sites, the antarctic continent is largely free of aerosol and trace gas sources, so that the main part of atmospheric trace compounds have to be advected by long range transport to Antarctica or has its source region in the surrounding Southern Ocean.
The main task of the Neumayer air chemistry observatory is to provide continuous, year-round as well as long-term data records for important gaseous and particulate trace components of the troposphere. Furthermore, the measuring program is also concerned with some aspects of the chemistry of snow and firn as well as the stratosphere and upper troposphere.
The Neumayer air chemistry observatory is one of only very few comparable clean air laboratories operated in Antarctica with an extensive scientific program, partly established since 1982. There is a strong scientific cooperation with the meteorological observatory. Both observatories are part of the GAW (Global Atmosphere Watch) global station network.
A main aspect of studying tropospheric chemistry in Antarctica is the need to interpret records of trace compounds found in firn and ice cores. Such records can be used to derive informations about climate, composition and chemistry of the paleo-atmosphere, provided atmospheric chemistry, the natural atmospheric nitrogen, sulfur and carbon cycling in the present and the physico-chemical processes of air to snow transfer are well characterised. With the realisation of deep drilling activities on the central Antarctic ice sheet (EPICA-project), the need for recent atmospheric data for interpretation of ice core records is strongly emphasized. On site, one of the nine over-winterer, usually an air-chemist or meteorologist, is responsible for the observatory.