The Causes of Sudden Windstorm Inducing a Deadly Threat to Coastal Safety: A Case Study for the Fishing Boat Overturning on February 28, 2018

Abstract

The incidence of overturning fishing vessels was approximately 2.7% of the total number of incidents involving fishing vessels in 2017, which is much smaller than that of engine failures or collisions, but it cannot be overlooked easily considering the damage scale (property and human life). In particular, after the sinking of the MV Sewol, also referred to as the Sewol Ferry Disaster, in 2014, the ship incident along with the casualties has been a great shock and trauma to the Korean people so far. On the afternoon of February 28, 2018, the fishing boat, Keun-Ryong, overturned in the open sea in front of Wando Island, causing seven casualties (two deaths and five missing persons) that also caused the shockwaves through the social community in Korea. According to media reports, the national coast guard deduced that the fishing vessel faced an unexpected condition and the crews could not press the distress signal button. In addition, bad weather condition due to wind gusts was considered the main cause. The instantaneous maximum wind speed in the shore near the accident area reached 20.7 m/s, but the quantitative wind speed at the accident spot was not known due to the absence of weather observations. To determine if a strong wind gust can overturn a fishing boat and to overcome the limitation due to the absence of weather observations in the open sea, high-resolution modelling was carried out using the WRF model in this study. A range of observation data were used to verify the model prediction as well as performance and to analyze the atmospheric instability between the upper and lower levels. Efforts need to be made prevent such accidents from recurring by predicting when similar weather conditions occur in the future.