Bull. Jpn. Soc. Fish. Oceanogr. 78(2), Page 86-96, 2014   Sudden Rise of Sea Surface Temperature in the Goto Nada-Amakusa Nada in Early Spring 2007 Kenji Morinaga1a†, Norihisa Nakagawa2, Takeshi Taneda3, Taku Yoshimura3, Kouji Tanaka4 and Nobuo Takagi5 1 Research Management Department, Fisheries Research Agency, 2-3-3 Minatomirai, Yokohama, Kanagawa 220-6115, Japan a Present: National Research Institute of Fisheries Science, Fisheries Research Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa 236-8648, Japan 2 National Research Institute of Fisheries and Environment of Inland Sea, 2-17-5 Fisheries Research Agency, Maruishi, Hatsukaichi, Hiroshima 739-0452, Japan 3 Seikai National Fisheries Research Institute, Fisheries Research Agency, 1551-8 Taira, Nagasaki, Nagasaki 851-2213, Japan 4 Kagoshima Prefectural Kumage Bureau, 7590 Takadaue, Iwamoto, Nishinoomote, Kagoshima 891-3192, Japan 5 Nagasaki Prefectural Institute of Fisheries, 1551-4 Taira, Nagasaki, Nagasaki 851-2213, Japan † E-mail: kenjim@affrc.go.jp In order to elucidate the effect of short-time variability of ocean condition on the fisheries catch, we executed intensive monitoring of sea surface temperature in the coastal water of western Kyushu Island from 2000 to 2007. The monitoring was conducted by the continuous SST recording at the four coastal stations, on-board SST measurement from a ferry boat, and CTD observation by fisheries research vessels. The SST monitoring revealed the occurrence of a sudden rise in SST in the monitored region in the early spring of 2007. With the aid of satellite infrared images, it is shown that this warm water was derived from the northern edge of the Kuroshio and propagated to this region via two routes; offshore and coastal. The warm water supplied by the offshore route formed an anti-cyclonic eddy in the central part of the Goto and Amakusa Nada, which contributed to the continuous high temperature condition in the long term over one month. The warm water with thickness of 100 m supplied from the coastal path reached far north to the north part of Goto Nada. The monitoring data suggested that the propagation of warm water to western Kyushu occurred in the other monitoring season while the rise of SST would be obscure because of small temperature differences between the coastal and offshore waters. Key words: coastal water temperature, Kuroshio fluctuation, sudden rise of SST, west coast of Kyushu Island