ICE-POP2018: A Campaign to Better Understand Snowfall in the Yeongdong Region

The 23rd Winter Olympic and the 13th Paralympic Games were held in PyeongChang, Korea on February-March, 2018. It was a good opportunity for the meteorologists to understand mountain meteorology over complex terrain areas like PyeongChang. National Institute of Meteorological Sciences (NIMS) has been working on the International Collaborative Experiments for PyeongChang Olympic and Paralympic 2018 (ICE-POP 2018) project. The results of ICE-POP 2018 observation part could be used to improve the accuracy of nowcasting and short-range forecast systems in the mountainous regions. High Impact Weather Research Center (HIWRC) participated in the observation part of the ICE-POP 2018. In order to characterize lake-effect snowstorm and orographic enhancement on the evolution of snow clouds over the Yeongdong region, an intensive observation campaign was carried out during the winter period from December 2016 to March 2018. Synoptic observations, radars, wind profilers, multi-purpose aircraft, observing ship, and mobile observation vehicles were intensively used in this campaign. A thundersnow case which occurred on 20 January 2017 has been analysed as one of the case studies using air sondes, vertical wind profilers, radiometers, radars, satellites to find the vertical wind and temperature characteristics of this case. In this case strong convective instability with a temperature decrease of more than –18℃/km was observed at 4 to 6 km altitude. This is similar to the features of the cold frontal precipitation of mid-latitude cyclones unlike other extreme snowfall cases. As a result, the case of Yeongdong region was analyzed as a system combining the effects of cold frontal precipitation and convective precipitation. Analysis of the data collected by air sonde observing platforms combined with other remote sensing measurements will provide new insights into the mechanisms contributing to a unique perspective on snowfall over Yeongdong region.