TRANSFER OF ATMOSPHERIC CONSTITUENTS INTO AN ALPINE SNOW FIELD

Simultaneous aerosol and snow sampling was performed during a field campaign at the Alpine site Weissfluhjoch Davos, Switzerland (2540 m a.s.l.) from 1 January through 30 March 1988. In addition, a snow pit was sampled on 30 March 1988. Very good agreement between the new snow and pit snow samples was found for the measured major ions as well as for the stable isotopes deltaO-18 and deltaD. Thus, snow pit samples obtained at this site during the winter months yield representative deposition patterns with a conserved stratigraphy. Generally, concentrations in snow were very low, with 3.5, 8.5, 5.2 and 2.4 mueq l-1 for Cl-, NO3-, SO42- and NH4+, respectively. The Cl-36 and Be-10 concentrations as well as the Be-10/Cl-36 ratios were comparable to the ones measured at Arctic sites. With the exception of NO3-, no linear relation was obtained between atmospheric and snow concentrations, showing that the concept of scavenging ratios must be used with caution when looking at single snowfall events. The following precipitation-weighted mean scavenging ratios were found: 300 for NH4+, 350 for SO42-, 940 for total NO3- (NO3- + HNO3), 175 for Pb-210, and 750 for Be-10.