Since 1970, the Port and Harbour Research Institute has been cooperating with the Bureau of Port and Harbours, Ministry of Transport, and its associated agencies, on the coastal wave observation at their network stations.
　The P.H.R.I. has been processing and analyzing the wave records obtained at these stations, and has published the wave statistics in a series of reports (up to 1979, the title of the reports were Annual Report on Wave observation at Chosen Points).
　This Technical Note is the 1987 version of the series, and covers the wave data obtained throughout 1987 at the following 37 network stations.
Japan Sea : Rumoi, Setana, Fukaura, Sakata, Hajikizaki, Aga, Niigata-hishi, Wajima, Kanazawa, Fukui, Tottori, Hamada, Ainoshima, Genkainada.
Okhotsk Sea : Monbetsu.
Pacific Ocean : Tomakomai, Mutsu-ogawara, Hachinohe, Miyako, Kamaishi, Sendai, Soma, Onahama, Hitachinaka, Kashima, Hamakanaya, Kabu, Shinomisaki, Gobo, kobe, Kochi, Aburatsu,Shibushi, Nakagusuku.
East China Sea : Iojima, Naze, Naha.
　The wave statistics at each station are presehted in the following forms :
(1)the largest significant wave at each station since the observation started.
(2)the maximum and the mean significant waves during the year.
(3)the joint distribution of the significant wave height and periods.
(4)the wave characteristic parameters during outstanding extreme sea states.
　The annual statistics show that the average wave heights over the year for northern part of the Japan Sea are higher than those of normal years. In order sea, the average wave heights over the year are the same as those of normal years.
　The records of largest significant waves were renewed at the following eight obserivation stations.
　Hamada (H1/3=7.81m,T1/3=119.s), Ainoshima (H1/3=5.61m, T1/3=12.1s),
　Genkainada (H1/3=7.72m,T1/3=12.3s) Iojima(H1/3=6.81m,T1/3=12.1s),
　Naze (H1/3=7.49m,T1/3=11.1s), Miyako (H1/3=4.62m,T1/3=11.0s),
　Shionomisaki (H1/3=8.35m,T1/3=11.3s), Gobo (H1/3=11.37m,T1/3=13.8s)