Arctic aerosols in Greenland

Elemental composition of Arctic aerosols is being studied on the Greenland Icecap and in northeast Greenland to determine the level, composition, seasonal variation and origin of the aerosols, of which little is known in the remote and elevated central region. In particular, the degree of penetration of arctic haze aerosols is of interest since this may cause perturbations of climatic parameters.

Arctic haze aerosols have previously been found at four coastal sites notably in north Greenland. Receptor modelling of the aerosol by factor analysis revealed three to fivecomponents of remote origin from both natural and anthropogenic sources. In north Greenland the anthropogenic components exhibited large annual cycles with pronounced maxima in winter caused by long-range atmospheric transport from midlatitude areas. These measurements have been resumed as a reference to the Icecap Experiment.

On the Icecap, aerosol samples are being collected in two size ranges on a continuous basis concurrent with the Greenland Icecore Programme 1989–1993 at Summit, 3200 m a.s.l. The sampling equipment is designed for collection of weekly samples especially suited for PIXE analysis, retrieval once a year, automatic operation under extremely cold conditions and very low energy consumption. Preliminary results from samples covering for the first time also the winter season on the central Icecap are discussed in relation to arctic haze occurrences at sea level.