Summary
IWAKUNI/KURE
SUMMARY
The conclusions reached by this study are first that Kure Harbor particularly the anchorage area in the Outer Harbor is the most favorable typhoon "haven" in Japan from a meteorological perspective but is normally too crowded with commercial vessels to be a viable refuge for U.S. Navy ships. Secondly, the Port of Iwakuni (military), although not recommended as a "haven," has an easily accessible anchorage area outside the port in Hiroshima Bay which is considered safe during typhoon passage.
These conclusions are based on the following:
1 The location and topography of the entire Iwakuni/Kure area significantly reduces the effects of winds attending tropical cyclones.
2. Anchor holding in the designated anchorage areas is rated as excellent.
3. Surge effect is almost negligible and wave heights are not severe in the designated anchorage areas.
4.Conversations with local harbor and meteorology officials and JMSDF Kure District Headquarters Staff.
The mountainous terrain of the islands of Honshu, Kyushu and Shikoku, with elevations exceeding 3000 ft, would lead one to expect that the winds of a tropical cyclone would be greatly reduced before reaching the Hiroshima Bay region. This is, in fact, the case when storms pass either to the west or the east of the bay region.
When storms pass to the west, the wind will normally be reduced 35-50% while storms passing to the east will usually have their winds reduced approximately 60%. Also it appears that southerly winds coming through the Bongo Straits and Inland Sea have the path of least resistance into the Hiroshima Bay area. Generally this would be the case when a storm passes to the west. Further, a very strong storm passing directly through the Bongo Straits would probably give the worst conditions in the Hiroshima Bay region.
Due to the relative openness of the Port of Iwakuni (military), neither the Inner Harbor nor the anchorages are recommended as safe locations during tropical cyclone passage. Area "E" southeast of Iwakuni Harbor and Area "F" in Kure Harbor, shown in Figure 1 are the locations recommended in the event of a strong tropical cyclone. During the site visit in October 2009, JMSDF Staff and several of the ship's agents stated that the large number of ships seeking refuge in Kure Harbor (Area "F") does not normally allow for a safe distance between deep-draft ships in the Harbor. There should be no problem of crowding by other ships or traffic in Area "E".
The Iwakuni and Kure Typhoon Haven evaluation was prepared
by G. Handlers and S. Brand of Science Applications International Corporation (SAIC), Monterey, CA.
Source: http://www.nrlmry.navy.mil/port_studies/thh-nc/japan/iwakuni_kure/text/summary.htm
