Moon, Hyejin*† ･ Kim, Jinwon** ･ Kim, Jin-Uk*** ･ Byon, Jae-Young**** ･ Byun, Young-Hwa***** and Lee, Myoung-Hee******
Atmospheric rivers (ARs) that are characterized by an elongated plume of intense vertically-integrated water-vapor transport (IVT) in the atmosphere, are critical in the occurrence of heavy precipitation and hydrologic extremes, especially in the mid-latitudes, in addition to the poleward water-vapor transport. Although ARs affect regional hydrology and can lead to natural disasters, few studies have examined the relationship between ARs and continuous precipitation events like storms. This study analyzes the climatology of AR-related precipitation in South Korea (SK) on the basis of storm events. In SK, AR storms undergo a well-defined annual cycle with a peak in July and outnumber non-AR storms in all months. AR (non-AR) storm duration exhibits an annual cycle with the peak in August (no systematic annual cycle). AR storms are related to larger (smaller) IVT over East Asian coastal regions (western North Pacific) compared to non-AR storms. The IVT difference appears to lead to precipitation differences such that AR storms dominate non-AR storms in monthly and annual-total precipitation, especially in summer. The effects of AR storms on monthly storm-total and storm-mean precipitation are strongest in the central (July) and southern (August) parts of SK and decrease gradually towards the north. Seasonal variations in the occurrence and intensity of AR storms and associated daily precipitation in SK are characterized by a small number of heavy-precipitating AR storms in June and September and a large number of heavy-precipitating AR storms in July and August.
Atmospheric River, Water Vapor Transport, Storm, Precipitation
1402-03.pdf
