Characterization of the inter-annual, seasonal, and diurnal variations of condensation particle concentrations at Neumayer, Antarctica R. Weller1, A. Minikin2, D. Wagenbach3, and V. Dreiling4,* 1Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany 2Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, 82234 Weßling, Germany 3Institut für Umweltphysik, University Heidelberg, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany 4Institut für Physik der Atmosphäre, Universität Mainz, 55099 Mainz, Germany *now at: Deutsches Zentrum für Luft- und Raumfahrt (DLR), Flugexperimente, Oberpfaffenhofen, 82234 Weßling, Germany
Abstract. Continuous condensation particle (CP) observations were conducted from 1984
through 2009 at Neumayer Station under stringent contamination control.
During this period, the CP concentration (median 258 cm−3) showed no
significant long term trend but exhibited a pronounced seasonality
characterized by a stepwise increase starting in September and reaching its
annual maximum of around 103 cm−3 in March. Minimum values below
102 cm–3 were observed during June/July. Dedicated time series
analyses in the time and frequency domain revealed no significant
correlations between inter-annual CP concentration variations and
atmospheric circulation indices like Southern Annular Mode (SAM) or Southern
Ocean Index (SOI). The impact of the Pinatubo volcanic eruption and strong
El Niño events did not affect CP concentrations. From thermodenuder
experiments we deduced that the portion of volatile (at 125 °C) and
semi-volatile (at 250 °C) particles which could be both associated with
biogenic sulfur aerosol, was maximum during austral summer, while during
winter non-volatile sea salt particles dominated. During September through
April we could frequently observe enhanced concentrations of ultrafine
particles within the nucleation mode (between 3 nm and 7 nm particle
diameter), preferentially in the afternoon.
Citation: Weller, R., Minikin, A., Wagenbach, D., and Dreiling, V.: Characterization of the inter-annual, seasonal, and diurnal variations of condensation particle concentrations at Neumayer, Antarctica, Atmos. Chem. Phys., 11, 13243-13257, doi:10.5194/acp-11-13243-2011, 2011.