Implementation of the airborne cloud seeding experiments for snow enhancement

An airborne cloud seeding experiment for snow enhancement using a small aircraft was conducted at Pyeongchang area where northeastern region of South Korea on 13 March 2013 by the National Institute of Meteorological Research(NIMR) of Korea Meteorological Administration(KMA). The target area of the experiment was Yongpyeong resort near Daegwallyeong region. About 900 g of seeding material, silver iodide(AgI), was spread into a stratocumulus cloud crossing wind direction. During this airborne experiment, a northerly wind was dominant around the experiment area. The number concentration of aerosol was observed by a condensation particle counter(CPC) equipped inside the seeding aircraft. The seeding altitude was about 2.8 km near cloud top. The cloud temperature was between -10oC and -12oC, which was sufficient condition for nucleation of silver iodide particles to be an ice nuclei. The number concentration of aerosol observed by the CPC showed an average of 1.8 times of increase from that of the un-seeded region. Furthermore the number concentration of aerosol observed by the PARSIVEL at Yongpyeong resort was 3 times more than that before seeding causing the increase of fresh snow cover in 0.6 cm. From this result, it was concluded that the airborne seeding seemed to have influenced in the increase of the fresh snow in some degree.