Multiscale drivers of catastrophic heavy rainfall event in early August 2022 in South Korea

On 8–11 August 2022, South Korea experienced a catastrophic heavy rainfall event (HRE) with 14 fatalities. To elucidate its driving mechanisms, the present study performs a multiscale analysis by hierarchically delineating the synoptic and large-scale characteristics of the HRE. Its synoptic condition was featured by the confrontation of the western North Pacific subtropical high and the continental cyclone in the north of the Korean Peninsula. At their interface, a tremendous amount of moisture was transported in an elongated shape (i.e., atmospheric river) along with strong frontogenetic activity. This provided a favorable environment for local convective instability. The continental cyclone maintained throughout the HRE period although a transient cyclone was also superposed in the early stage of the HRE. A persistent cyclonic circulation in the north of the Korean Peninsula was origi…