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East Formosa Sea and the waters of the Okinawan archipelago (20 to 30 N. , 



130° E.) 



120° to 



The waters of the East China Sea, east of the 100-fathom line and east of the Bashi 

 Strait within the range of 20 to 30 N. , 120 to 130 E. will be described as the East Formosa 

 Sea and the waters of the Okinawan archipelago. 



This area is almost all within the Japan current (Kuroshio) and, stated very broadly, 

 the currents flow north or northeast throughout the year. However, in the western part of the 

 area during the winter the effect of a cold current flowing south along the continent is fairly 

 conspicuous. Furthermore, on the east side of the main Kuroshio current there is a great gyrad 

 flowing clockwise. 



As this sea area stretches from the tropics through the subtropics to the temperate 

 zone, there are rather conspicuous local and seasonal variations in water temperature and it ia 

 difficult to mjike a general discussion of the area as a whole. 



Table 40 shows the chainges in water temperature in the Bashi Strait at the extreme 

 southern linnit of this sea area. 



Table 40. --Water tennperatures in the vicinity of Bashi 

 Strait (from Formosan Fishery Experiment 

 Station Report for 1932) 



The following table (table 41) shows the water temperatures for each month in the 

 central part of the area at about the middle of the line between Suo (Fornnosa) and Yonakuni 

 Island. The table is based on the regular sectional observations made by the Fisheries Experi- 

 ment Station of the former Taiwan Government-General but do not all represent data from the 

 same year, being averages of 13 years from 1919 to 1932. 



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 According to this table the minimum surface water temperatures were 23 C. in 



March and the maximum 29. 1 C. in August. Between 25 meters and 200 meters the minimum 



was in March and the maxin-ium in September. 



The data for the most northern part of this sea area are unequally distributed 

 seasonally and therefore it is difficult to show changes throughout the year. Table 42 shows 

 changes in the water tennperatures based on data from sectional observations carried out by the 

 Kagoshima Prefecture Fisheries Experiment Station. The values shown in the table are those 

 from a station 50 miles off Yakushima on a line connecting Yakushima and Oshinna. The data 

 do not all represent the same year but are a collection of data covering several years. 



Comparing these three tables, it appears that there is little difference between 



tables 40 and 41. Even in table 42 little difference can be seen in the summer, but in the winter 



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the tennperatures are 2 - 3 C. lower. 



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