Chapter 5 Global Tsunamis Some important tsunamis in various parts of the globe are cataloged and important deductions from the data are emphasized. In the first section the western part of the Pacific Ocean, specifically Japan, USSR, Australia, and New Zealand will be considered. In Section 2 the islands in the Pacific Ocean, such as Hawaii, Aleutians, Tahiti, and Alaska will be discussed. (Although Alaska is part of the North American continent, it is more convenient to study tsunamis of Alaska and the Aleutians together.) In the third section, the tsunamis on the west coasts of the North (excluding Alaska) and South American continents will be discussed. In Section 4, the Atlantic Ocean tsunamis and tsunamis in Europe, Middle East, and Asia will be treated. 5.1 Tsunamis in Japan, USSR, Australia, and New Zealand TSUNAMISIN JAPAN The Pacific coast of northeastern Japan has been referred to as the Sanriku coast because it contains the three Riku provinces - Rikuzen, Rikutyu, and Rikuoku. TABLE5.1 lists 15 tsunamis that occurred in Japan from 869 to 1933 (Imamura 1934). In addition, information will be provided on some of the very destructive tsunamis, and on tsunamis subsequent to 1934. The tsunami following the Sanriku earthquake of June 15, 1896, destroyed about 12,000 houses and affected 322-483 km of coastline north of Sendai. There were mainly three waves and the greatest amplitude was 15.2 m (Milne 1896). Practically every town and village between 30" 15'N, 141'30'E and 40"30'N, 13 1 "30'E was destroyed. A major earthquake occurred in Sagami Bay on Sept. 1, 1923 (Shiratori 1925), and only 5 min after the earthquake a tsunami invaded Sagami Bay, Tokyo Bay, and the Pacific coast of Japan. Figure 5.1 shows the distribution of water level at various locations (Davison 1931). The tsunami attained maximum amplitude of 11 m, about 455 houses were destroyed, and about 160 persons killed. The epicenter (38.2'N, 144.0'E) of the Sanriku earthquake of Mar. 3, 1933, was not on land, hence, destruction by the earthquake itself was small. Most of the destruction was caused by the tsunami and about 5000 houses were destroyed. At some places (Sirahama and Ryori) amplitudes as large as 28.7 m were attained. Tsunamis rarely occur in the Sea of Japan (Kishinouye and Iida 1939). An insignificant tsunami occurred on May 1, 1939, in the Oga Peninsula following the Oga earthquake. 215 TABLE5. I. List of tsunamis prior to 1934 on the Sanriku Coast. (Imamura 1934) Remarks July 13, 869 epicenter under Pacific Ocean off Sanriku coast; about 1000 people killed Dec. 2, 1611 epicenter under Pacific Ocean off Sanriku coast; about 3000 people killed; possible amplitude of 25 m Sept. 9. 1616 epicenter under Pacific Ocean OK Sanriku coast; tsunami probably small July 3. 1640 following an eruption of the volcano Komagatake; tsunami killed about 700 people Apr. 13, 1677 following an earthquake in Sanriku district; tsunami caused only property damage; people fled and no casualties ? ? 1689 following a Sanriku earthquake; probably small tsunami Jan. 29. 1763 following an earthquake in the north Sanriku district; tsunami swept the coast Feb. 17, 1793 following an earthquake near Rikutyu; tsunami killed 12 or 13 people July 20, 1835 following an earthquake near Rikuzen; tsunami generated: casualties not known Apr. 25, 1843 following an earthquake in ea3 Hokkaido; details of tsunami not known Aug. 23. 1856 following an eruption of the volcano Kamagatake; tsunami killed at least 21 people June 15, 1896 following an earthquake in Sanriku; tsunami very destructive, killed at least 27,000 people Mar. 22, 1894 following an earthquake in eastern Hokkaido; tsunami caused some damage Aug. 5, 1897 following an earthquake in Rikuzen; tsunami was small Mar. 3, 1933 following the Sanriku earthquake; tsunami very destructive, killed at least 2986 people A severe earthquake occurred in western Hokkaido on Aug. 2, 1940. About 1 h after the earthquake a tsunami invaded the Hokkaido coast. Seven people were killed and about 1000 fishing boats were swept into the ocean (Miyabe 1940). Figure 5.2 shows tsunami amplitudes. A severe earthquake occurred on Dec. 7, 1944, with epicenter at 34"N, 143"E. A tsunami of considerable amplitude was generated and effects were felt as far east as Simoda Harbor and as far west as Siworomsaki (Omote 1946). Along the coasts of Sima and the Kii Peninsula, heights were as large as 8 m; along the coasts of Ise Bay and Atumi Bay, the height was 2 m. Amplitudes were small along the Ensywnada coast but enormous heights were achieved in the bays of Owase, Atasika, Nisiki, and Yosizu. 2 16 FIG.5.1. Distribution of tsunami wave heights (m) in Sagami Bay. (Davison 1931) On Dec. 21, 1946, a severe earthquake occurred in southwestern Japan with epicenter at 33.0°N, 135.6"E. The generated tsunami invaded the coasts of Shikoku and the Kii Peninsula. The largest amplitude was 6 m (Nagata 1950) and on the coast of the Kii Peninsula, initial withdrawal occurred. The most severe damage occurred on the coast of Kochi prefecture where 1451 houses were swept away (Nasu and Shirai 1947). The Nankai earthquake tsunami was studied in detail by Shimozuru and Akima (1952) and Rikitake and Murauchi (1947). On Mar. 4, 1952, a severe earthquake (referred to as the Tokachi earth- quake) occurred, followed by a tsunami, with epicenter at 42'N, 144"E, about 60 km east of Erimo-Misaki, at the southwestern tip of Hokkaido (Suzuki and Nakamura 1953; Suzuki et al. 1953; Yoshida et al. 1953; Kat0 et al. 1953; and Watanabe 1956). 2 17 FIG. 5.2. Distribution of tsunami height (m) for 1940 tsunami. Tsunami sources inferred from the present (solid line) and Miyabe's analyses (dotted line). (Hatori 1969) TABLE5.2. Tsunami of Feb. 27, 1961, as recorded on tide gages (all times Japanese Standard Time). Wave originated at earthquake epicenter off the coast of Hiuganada (31.7"N, 131.7'E) at 03: 11. (Takahasi and Hatori 1961) Max. Arrival amplitude Max. time UP, time amplitude Period Tide station (h) bin) down (A) @in) (em) (min) Naze 04 23 + 04 52 13 20 Nishino-omote 04 00 + 06 00 25 Makurazaki 04 27 + 05 32 13 16 Namimi 03 30 + 04 20 12 Suzureishi 03 30 + 04 18 12 Aburatsu 03 14 + 03 51 45 22 Miyazaki 03 35 + 03 42 12 Hosojima 03 22 + 05 22 78 20 Hosojima, (New Harbor) 03 25 + 05 55 124 Tokai 03 35 + 03 42 13 18 Hebizak 04 00 + 05 IO IO 19 Yavatahama 04 25 + 06 30 28 22 Uwajima 04 12 + 06 53 18 22 Hosogi 03 58 + 04 55 17 20 Misho 04 08 + 07 16 70 30 Tosa-Shimizu 03 42 + 04 12 96 22 Tosa-Shimoda 03 55 + 04 47 10 20 Urado 04 08 + 06 08 20 18 Kochi 04 15 + 06 05 17 20 Kushimoto 03 46 + 05 25 36 23 Aburatsubo 05 36 + 07 56 6 16 Mera 05 32 + 13 25 35 22 Hachijo Is. 05 10 ? ? 3 ? 218 TABLE5.3. Tsunami of Mar. 28, 1964, as recorded by tide gages and tsunami recorders in Japan. (Hatori 1965~) Initial wave Maximum wave Travel Travel time Height' Period time Height' Period Tide station (h) (mln) (cm) (mrn) (A) Win) (cm) (mln) Wakkanai 6 39 6 50 39 09 34 35 Mon betsu 7 16 7 70 18 34 IO 40 Abashiri 6 04 4 46 30 49 I2 50 Hanasaki 6 34 8 60 15 04 36 IO Kushiro 6 55 20 45 45 40 40 42 Urakawa 7 12 5 40 18 14 25 28 Hakodate 7 34 II 150 22 17 33 35 Aomori 9 04 8 I40 26 14 32 IO0 Asamushi 8 29 IO I30 25 09 46 100 Hachinohe 7 24 18 50 26 44 60 30 Miyako 7 04 9 60 16 02 14 44 Kamaishi 6 44 15 30 16 34 38 22 Ofunato 7 14 18 40 12 44 75 40 Enoshimaa 7 08 7 80 15 39 I5 60 Onagawa 7 24 17 70 17 44 50 45 Onahama 7 29 7 50 16 34 35 23 Choshi 7 39 7 55 20 04 36 40 Mera 7 06 6 7 23 34 33 23 Kanayaa 7 30 7 70 21 14 17 35 Tokyo 9 02 4 65 22 59 IO 56 Yokosuka 8 00 5 60 22 30 17 30 Aburatsubo 7 48 6 15 22 32 18 15 Hachijo Is. a 7 47 2 8 22 14 7 20 Uchiura 7 34 6 50 16 29 I2 23 Shimizu 7 44 4 20 25 19 6 40 Omaezaki 7 04 3 18 22 12 30 22 Onizaki 9 41 6 25 19 54 IO 35 Toba II 24 4 50 18 24 15 15 Uragami 9 29 8 26 18 36 25 28 Kushimoto 9 14 6 15 26 24 45 28 Kainan IO 12 5 30 20 24 15 28 Kochi II 06 8 40 25 04 20 20 Tosa-Shimizu I1 24 4 26 22 30 24 22 Hosojima 12 44 2 20 27 07 12 20 Aoshimaa IO 44 2 - 26 57 15 30 Aburatsu 10 28 8 23 25 06 39 25 Naze 10 32 8 18 22 32 20 23 aTsunami observatory. 'Crest height above the ordinary tide level An earthquake on Nov. 6, 1958, near Iturup Island, generated a tsunami. During the International Geophysical Year (IGY), special instruments were placed at Miyagi-Enoshima tsunami observatory.