Further analysis of CCN data at a mid-Antarctica Peninsula field site

Observations of very low atmospheric cloud condensation nuclei occurred about 10% of the daytime sampling periods at Palmer Station during February 1994. These measurements were not only observed following typical nuclei reducing weather events or phenomena. We do advocate the need and worthiness for a more comprehensive study to assess the frequency of low nuclei concentrations. The comprehensive study would include concurrent CCN activity spectra, individual nuclei or aerosol morphology and corresponding chemical composition, meteorology, atmospheric chemistry, and radiation measurements made simultaneously at least at Palmer. The study will contribute to the understanding of such very low nuclei event occurrence, to a more quantified assessment of their climatic relevance for this region, and to the development of a more viable aerosol measurement system. A suggested functional definition for a viable aerosol measurement system is provided. •CCN concentration measurements were