Determining the features of meteorological conditions inducing Kyucho around the Noto Peninsula, aiming to prevent the Kyucho disasters

Abstract

Around the eastern coast of Noto Peninsula, events of sudden strong currents (Kyucho) often cause serious damages to set-net fisheries. Previous studies have suggested that the Kyucho around Noto Peninsula are induced by meteorological disturbances. Here we statistically examined the features of such disturbances in order to understand the mechanisms of the events and to foresee the occurrence, aiming to establish effective measures to prevent the disasters. As the result, we revealed that Kyucho damages often occurred after strong southwesterly exceeding 20 m・s^-1 at Hegurajima Island due to typhoon with central pressure <990 hPa passing south of 41°N at 137°E. The maximum current velocity (v_max) at the eastern coast of the Noto Peninsula was positively correlated with the maximum of the southwest component of wind at Hegurajima (w_max). Conversely, v_max was negatively correlated with the delay of the appearance of v_max after the time of the appearance of w_max. Using these relationships, we propose simple methods to predict the occurrence time and v_max of Kyucho from the forecast information of the magnitude and passage of a typhoon.