Introduction to the First Large-Scale Cloud Physics Experimental Chamber in Korea: Design, Construction, and Initial Experiments

The National Institute of Meteorological Sciences has recently constructed a Korea Cloud Physics Experimental Chamber (K-CPEC) to investigate the fundamental processes of cloud formation and implement a rainfall enhancement. The K-CPEC is capable of adiabatic expansion and covers temperatures ranging from –70℃ to 60℃, pressures from 1,013 hPa to 30 hPa, and relative humidity from 10% to 95%. It consists of an inner and outer chamber, with the outer chamber (5m x 5m) controlling pressure and the inner chamber (3m x 3m) controlling temperature to minimize heat loss during experiments. Notably, the inner chamber is constructed using dual materials of copper and stainless steel, a first in the world, which increases thermal efficiency with copper and ensures structural safety of the inner chamber with stainless steel. The K-CPEC is equipped with various observation equipment, such as pressure, temperature, and humidity sensors, an optical particle counter, a cloud condensation nuclei counter, an ice nuclei counter, and a cloud particles imager. Through temperature and pressure control, the K-CPEC can replicate cloud formation processes, and the observation equipment can measure characteristics of aerosol, cloud particles, and ice crystals. Performance testing has confirmed that the K-CPEC is a valuable facility for activating various types of aerosol particles and verifying cloud particle and ice crystal formation processes. Research using a cloud chamber is a research method introduced for the first time in Korea, and the cloud generation experimental procedure and observation method have not yet been systematized. Therefore, it is necessary to ensure reproducibility and reliability by performing repeated experiments according to experimental analysis procedures developed in the future. Through this, it will be possible to lay the foundation for various studies using cloud chambers and increase their usability.

 

This research has been supported by the "Research on Weather Modification and Cloud Physics"(KMA2018-00224) project of NIMS/KMA.