TEMPERATURE OF THE HYDROSPHERE 189 



Temperatures of the Mediterraneans and Epicontinental 

 Seas Dependent on the Large Oceans. As a general chracteris- 

 tic of mediterraneans may be noted the deep homothermal bottom 

 layer, wiiich, as a rule, has a somewhat higher temperature than 

 tliat of the neighboring ocean at tire, same depth. Thus the Roman 

 mediterranean has a temperature of 12.8° between 200 m. and 2,600 

 m., while the layers above this show a gradual increase to 25.0° at 

 the surface. The temperature of the Atlantic in the Bay of Cadiz 

 at 1,000 meters depth is normally not over 8°, though tlie outflow of 

 the warm mediterranean bottom water raises it to ir°, whereas in 

 depths of 2,000 m. the temperature of this part of the Atlantic is 

 only a little over 4° C. The Sea of Marmora below a depth of 220 

 to 350 m. to the bottom of 1,403 m. has a homothermal temperature 

 of 14.2°, which is the approximate winter temperature of the sur- 

 face water of the ^gean Sea. While thus the Marmora Sea has 

 a higher bottom temperature than the Mediterranean, the Black 

 Sea shows a much lower. Here, in summer, we have a typical dicho- 

 thermic stratification, the minimum temperature of 6.3° in the north- 

 ern part lying at 75 m., while the bottom at 131 m. has a temperature 

 of 8.3° C. In the central area the minimum temperature is 7.3° 

 and lies only 45 m. below the surface, while between 100 and 2,012 

 m. the bottom temperature rises from 8.5° to 9.1° C. In the 

 southern part the minimum temperature of 6.2° lies at 65 m., 

 the bottom temperature at 366 m. having risen to 8.9°. The South 

 China Sea shows a fall of 10° at 200 m. from the surface tempera- 

 ture of 24° characteristic of the upper 50 m. At 1,000 m. the tem- 

 perature is 3.9°, at 1,500 m. 2.6°, but below 1,600 m. to the bottom 

 (3,480 m.) a homothermal temperature of 2.5° obtains, which is the 

 average temperature of the Pacific at 1,500 meters. That the 

 deeper strata of the China Sea are uninfluenced by the correspond- 

 ingly colder waters of the Pacific, which sink to 1.6° at 3,000 m., 

 indicates that the submarine barrier of this sea is nowhere below 

 1,600 m. Similar conditions are found in the Celebes Sea, where a 

 homothermal state exists below 1,500 m., with a temperature of 

 3.67° C. In the Philippine waters, on the other hand, a homother- 

 mal condition with 10.9° exists from 500 m. to the bottom (1,280 

 meters), and in the neighboring Sulu Sea a temperature of 10.3° 

 characterizes the water from 730 m. to the bottom at 4,070 m. Here, 

 then, a greater separation from the Pacific is shown. The Red Sea 

 offers some striking features owing to its situation in the tropical 

 belt. It has the highest bottom temperatures of all mediterraneans, 

 this being, according to J. Luksch, uniformly at 21.5° from 700 m. 

 to its greatest depth at 2,200 m. This is associated with a salinity of 



