Semi-automated calibration procedure for cloud condensation nuclei (CCN) measurement

Cloud condensation nuclei (CCN) are atmospheric particles that play a crucial role in cloud formation and precipitation. Accurate knowledge of CCN concentrations is essential for understanding cloud microphysics. The detection of these particles is challenging due to their small size and mixture with non-hygroscopic particles. A cost-effective technique for CCN detection involves capturing atmospheric air in a supersaturated cloud chamber, where only CCN form water droplets, making them optically detectable and countable inside a very small sample volume. Precise measurement of this sample volume is vital for accurately estimating CCN concentrations. This research introduces the implementation of a semi-automated procedure for calibrating the sampling volume of a CCN counter. The semi-automated procedure enhances efficiency and practicality, showing a 1.6% difference compared to traditional volume measurement techniques. The results confirm the feasibility and effectiveness of the semi-automated calibration method in accurately measuring the sampling volume of the CCN counter.