430 Tides in the Mediterranean and Adjacent Seas 



at about h. The Gulf of Tartary co-oscillates with the diurnal tides with 

 the Sea of Japan without a nodal line, and the phase lags somewhat because 

 of frictional influences. 



Whereas the character of the tide in the Strait of Tsushima is still semi- 

 diurnal, it becomes in the entire Sea of Japan of a diurnal type with a value 

 of the ratio between 1-00 and 1 50 and then it resumes its semi-diurnal cha- 

 racter in the Gulf of Tartary. This phenomenon is not a consequence of 

 a greater prominence of the diurnal tides, but rather of the decrease of the 

 semi-diurnal tides in the large and deep interior sea. 



Muramoto (1932, p. 227) has made a survey of the ocean currents in the 

 Strait of Tsugaru on the basis of the current observations on two stations, 

 and has also tested the results on models. 



A hydrodynamical theory of the tides of the entire Sea of Japan including 

 the Strait of Tsushima and the Gulf of Tartary has been given by Ogura 

 on the basis of the canal theory. The computations by means of sixty six 

 cross-sections perpendicular to the "•Talweg" resulted for the semi-diurnal 

 tides in almost complete agreement with observations; the amphidromies 

 result of the co-oscillation of the water-masses of the Sea of Japan with the 

 tide in front of the Strait of Tsushima; the other communications with the 

 adjacent seas are unimportant. The diurnal tides do not agree as well and 

 Ogura is of the opinion that this is due mainly because we cannot neglect 

 the transport of 16 5 km 3 of water through the Strait of Tsugaru in 12 h 

 whereas the transport through the Strait of Tsushima is 32 km 3 . However, 

 it is not impossible that the independent tidal component of the diurnal tides 

 makes itself felt even though the amplitudes are small. Ogura (1932, p. 1) 

 has treated the tides of the Strait of Tsugaru theoretically and has obtained 

 a good agreement with the observations made by Muramoto. 



The Sea of Okhotsk communicates with the Pacific Ocean by the numerous 

 passages between the various Kuril islands; it also communicates with the 

 Sea of Japan by the Soya Strait (La Perouse Strait) between Sakhalin and 

 Hokkaido, and by the Gulf of Amur through the Gulf of Tartary, on the 

 other hand. The two latter communications, however, are of far less im- 

 portance than the former. Inside the chain of the Kuril Islands there is 

 a basin more than 3000 m (9800 ft) deep, but then the ocean bottom rises 

 rapidly up to 200 m (600 ft) towards the centre of the sea. The north-eastern 

 section of the Sea of Okhotsak is the Gulf of Penhinskaya which ends in 

 a narrow arm. 



The number of tidal stations on the Kuril Islands and along the coast 

 of Sakhalin is sufficiently large to give an outline of the tides. At the north 

 and north-west coast there are only few values available; at the west coast 

 of Kamchatka there are none. Table 62 gives the harmonic constants for 

 a series of localities and Fig. 184 shows, according to Ogura, for the M 2 tide 

 the co-tidal lines and the ranges 2(M 2 -\-S 2 ). 



