Tides in the Mediterranean and Adjacent Seas 433 



Tidal observations in the Gulf of Penzhinskaya are very scarce. With 

 / = 600 km and a mean depth of about 50 m, v will be about 1-5, which is 

 close to the resonance value. Therefore, if the amplitudes are large there will 

 be two nodal lines (amphidromies) for the semi-diurnal tide; one near the 

 opening, the other one near the closed end. The former is indicated in Ogura's 

 map, whereas he has transformed the latter in the narrow arm into a pro- 

 gressive wave. Whether this corresponds to the reality can only be decided by 

 observations. The range 2 (M 2 -\-S 2 ), which is 64 cm at the opening, increases 

 at the first antinode to a little above 200 cm, at the closed end to 318 cm, 

 which shows how strongly these water-masses co-oscillate with the external tide. 



The diurnal tide wave has a phase of about 10 h at the northern end of 

 the Kuril Islands and of 14A h at the north coast of the adjacent sea. Ac- 

 cording to the v value, one should expect an amphidromy; but according 

 to the available observations, there seems to be none. The range 2(A^ + 0!) 

 is very great and increases from the outside to the inside. The value of the 

 ratio determining the character of the tides in the vicinity of the semi- 

 diurnal amphidromies is quite high. Chaivo on Sakhalin has a ratio of over 6. 



The diurnal tides in the Gulf of Penzkinskaya are excessively large. They 

 are considerably intensified by resonance; at the closed end, Cap Astro- 

 nomicheski 2(# 1 + 0i) attains the value of 826 cm, which is the largest value 

 ever known for diurnal tides. Point Matugin has still 612 cm. However, 

 the ratio decreases from the opening into the Gulf of Penzhinskaya towards 

 the closed end from 6-4 to 2-6; this shows that the semi-diurnal tides, become 

 stronger relatively to the diurnal tides, which can also be concluded from 

 the v value. 



The tidal picture of the Sea of Okhotsk is still very uncertain. Moreover, 

 throughout a great part of the year, the central part of this sea is covered 

 with a thick layer of ice and the pack- and drift-ice masses do influence the 

 tide wave through friction (see vol. I). Whether this causes seasonal variations 

 in the harmonic constants and how this effects also the ranges on the coasts, 

 is still completely unknown. 



15. The Tides of the Bering Sea 



Harris (1904) part IV, p. 394 has made a first attempt to represent the 

 tides of this sea, basing himself on a very small number of observations. 

 Since then only few new tidal values have been added (see Table 63). The 

 establishments permit the following conclusion; the Pacific tide wave pro- 

 gresses westward, past the Alaskan Peninsula; then it penetrates north-west- 

 ward through the wider and deeper passages between the Aleutians, especially 

 between 170° and 175° west of Greenwich into the deep [3000 m (9840 ft) 

 to 4000 m (13,100 ft)] area of the Bering Sea and reaches the coast of Asia 

 almost simultaneously with an establishment of 4 h. The wave is retarded 

 against the shallower shelf area towards the north-east, and it seems as if 



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