Master Thesis
Direkte Eddy-Kovarianz-Messung vertikaler Aerosolflüsse mit einem Fast CPC
Fanny Kittler (01/2012-10/2012)
Support: Thomas Foken, Andreas Held
Since atmospheric aerosol particles affect the climate directly and indirectly and influence ecosystem balances with nutrients and pollutants via atmosphere-surface exchange, they are of great scientific interest. The high temporal resolution, which is required by the eddy-covariance technique to determine the vertical particle exchange, cannot be realized by commercial particle measurements. Because of these device limitations the vertical flux cannot be measured directly but rather be parameterized and as a result of this, will be underestimated. To analyze this underestimation, a setup with a combination of a new developed fast condensation particle counter and an eddycovariance system was constructed in the Fichtelgebirge Mountains in August of 2011. Particle fluxes from -15.6*106 m-2 s-1 to +9.1*106 m-2 s-1 are showing that deposition dominates at this site. The spectral analysis indicates, that white noise influences the high frequency range. Despite a small time constant of 0.1 s, the contribution to the vertical particle flux does not start before 0,6 Hz. Assumably, this leads to an underestimation of the flux.