Aerosol transport to the high Alpine sites Jungfraujoch (3454 m asl) and Colle Gnifetti (4452 m asl)

Abstract

Atmospheric transport processes, relevant to high Alpine sites, were deduced from 2 sets of aerosol records: a 9‐year record from the Jungfraujoch (3454 m) on the northern side of the Swiss Alps and a 2.5‐year record from Colle Gnifetti (4452 m) on the southern side. A classification scheme for synoptic weather types was applied to separate the aerosol data into groups corresponding to different atmospheric transport conditions. For both sites, vertical aerosol transport by thermally driven convection, acting between late spring and late summer, was found to be the dominant transport process. In summer, the thermally driven aerosol transport to both sites caused an increase of the seasonally averaged aerosol concentration between 0800 and 1800 local standard time by a factor of two. Under anticyclonic conditions, when subsidence on a synoptic scale is present, the thermally driven aerosol transport is most pronounced. Therefore, the aerosol determining thermal transport takes place within a synoptic scale vertical motion of opposite direction. Under cyclonic conditions, when lifting on a synoptic scale is present, the thermally driven aerosol transport is nearly absent. In winter, thermally driven convection does not contribute to the aerosol concentrations at both sites. Nevertheless, also in winter statistically significant differences in aerosol concentration were found between cyclonic and anticyclonic weather conditions, which can be attributed to the vertical transport acting on the synoptic scale. These differences in aerosol concentration were small compared to the corresponding differences in summer. Within the weather types, which are dominated by horizontal advection in the Alpine region, the aerosol concentrations are more diffcult to interpret with respect to the effective transport process.

Saharan dust events at the Jungfraujoch: detection by wavelength dependence of the single scattering albedo and first climatology analysis

“…The JFJ is prevalently situated in the free troposphere, but is influenced by convection of planetary boundary layer air during the warmer months (Baltensperger et al, 1997;Lugauer et al, 1998). Consequently all the measured aerosol parameters show a clear annual cycle with maximum values in July and August and minimum values in the NovemberJanuary period.…”

Surface-to-mountaintop transport characterised by radon observations at the Jungfraujoch

“…Following a different approach entirely, previous investigations (Collaud Coen et al, 2011;Lugauer et al, 1998) have found that circulation-pattern classifications (Huth et al, 2008) are useful for explaining the occurrence of anabatic conditions at Jungfraujoch. Many schemes have been developed (Demuzere et al, 2011;Philipp et al, 2010); for comparison with the radon-based method we selected the CAP9 scheme, a nine-class objective scheme based on mean sea level pressure in a domain centred on the Alps and implemented by MeteoSwiss (MeteoSwiss, 2012).…”

Temporal variations of perfluoroalkyl substances and polybrominated diphenyl ethers in alpine snow

“…a.s.l.) (Lugauer et al, 1998). Primary emission sources of particle-bound and gaseous PFASs include manufacturing processes, waste-related facilities and waste water treatment plants.…”