Simulation of storm waves and swell over the Pacific Coast of Japan during the typhoon of September 1935

Abstract

On 26 September, 58 ships of the Combined Fleet depart Hakodate and steam into therough northwest Pacific waters to conduct the concluding rounds of the exercises begunJuly 20. The mock engagements will take place between Honshu and the Kuriles. For theexercise, the First and Second Fleets as Blue Fleet will grapple against a temporarilyorganized `Fourth Fleet as Red Fleet. Near dawn the Red or Fourth Fleet is about 100miles off the east coast of Northern Honshu and steering southerly when it is alertedthat a large typhoon has blown up to the south and is advancing toward them at70-80km/hour over a 200 mile front. There is neither time nor sea room to get clear ofsuch a wide storm, so the Fleet has no choice but to batten hatches and attempt to rideit out. Course is maintained heading obliquely into the storm, and speed cut to 10 knots.A situation analagous to the famous Typhoon Cobra that struck the USNs Task Force38 off Luzon in December 1944 now ensues(http://www.combinedfleet.com/Fourth-Fleet-Incident.htm). A coupled process basedtide-wave-surge model (ADCIRC-UnSWAN) with the flexible FEM mesh has been usedto simulate the storm surge that occurred in September 1935. Typhoon and meteorologicalforcing inputs for the period, the end of Sep.,1935 are prepared via ECMWF-20C asbackground meteorological conditions and Holland type vortex typhoon fields based ontyphoon Malakas (201 Kuriles. For theexercise, the First and Second Fleets as Blue Fleet will grapple against a temporarilyorganized `Fourth Fleet as Red Fleet. Near dawn the Red or Fourth Fleet is about 100miles off the east coast of Northern Honshu and steering southerly when it is alertedthat a large typhoon has blown up to the south and is advancing toward them at70-80km/hour over a 200 mile front. There is neither time nor sea room to get clear ofsuch a wide storm, so the Fleet has no choice but to batten hatches and attempt to rideit out. Course is maintained heading obliquely into the storm, and speed cut to 10 knots.A situation analagous to the famous Typhoon Cobra that struck the USNs Task Force38 off Luzon in December 1944 now ensues(http://www.combinedfleet.com/Fourth-Fleet-Incident.htm). A coupled process basedtide-wave-surge model (ADCIRC-UnSWAN) with the flexible FEM mesh has been usedto simulate the storm surge that occurred in September 1935. Typhoon and meteorologicalforcing inputs for the period, the end of Sep.,1935 are prepared via ECMWF-20C asbackground meteorological conditions and Holland type vortex typhoon fields based ontyphoon Malakas (201