Concentrations of Cloud Condensation Nuclei (CCN) and Ice Nucleating Particles (INP) over the Southern Ocean during the Antarctic Circumnavigation Expedition
Abstract
In the framework of the 2016/17 Antarctic Circumnavigation Expedition (ACE) within the ACE-project "Study of Preindustrial-like Aerosol-Climate Effects" (SPACE) we conducted measurements concerning the concentrations of cloud condensation nuclei (CCN) and ice nucleating particles (INP). The unique ship-based circum-Antarctic data we gathered during the Austral summer makes an important addition to the to-date still sparse available aerosol data for the Southern Ocean. Our data will be useful for improving both climate models and satellite retrievals.
A CCN-100 cloud condensation nuclei counter by DMT was operated during the cruise, outputting CCN concentrations at 5 levels of supersaturation (0.15 to 1.0%). Fiber and Polycarbonate filters were sampled throughout the cruise for further analysis at our institute concerning INP concentrations (droplet freezing array method) and chemical composition of the sampled particles. CCN concentrations were in the 5 to 1300 #/cm3 range, with high values near the continents. During open-ocean sections of the cruise the lowest CCN concentrations were observed. Preliminary INP concentrations show a range of 0.1 to 100 #/m³, highest values on filters sampled in harbours. A connection between bulk chemistry and CCN number was pointed out by a first correlation analysis, while not holding true for INPs. The found high INP concentrations near continents could either mean a domination of sinks at the ocean or strong land-based sources. Using back-trajectories we look at the origin of the CCN- and INP-containing air-masses. We present preliminary results from our data analysis indicating promising opportunities for pinning down sources of both CCN and INP at the Southern Ocean.- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.A13G2525T
- Keywords:
-
- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0320 Cloud physics and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3310 Clouds and cloud feedbacks;
- ATMOSPHERIC PROCESSESDE: 3349 Polar meteorology;
- ATMOSPHERIC PROCESSES