Which is the Dead Sea?

Between the Balkan Peninsula in southeastern Europe and Asia Minor Peninsula in western Asia, there is an inland sea with an area of about 420,000 square kilometers, which is the Black Sea. Sailing on the Black Sea by boat, all you can see is dark cliffs and blue-brown water. This sea area looks lifeless.

The length of the Black Sea from east to west is1180km, and the narrowest point from north to south is 263km. There are huge mountains along the southeast coast, and the northwest coast is low-lying and basically a closed water body. Its eastern end crosses the Kerch Strait to reach the Sea of Azov; Southwest China can enter the Mediterranean Sea via Bosporus Strait, Marmarahoi Strait and Da Daniil Strait.

Although the salinity of the Black Sea is low, with an average salinity of less than 22‰, in some sea areas with water depth of 155-3 10 m, life is almost extinct, and fish dare not swim there, which is simply a "dead zone". What caused the Black Sea to become a lifeless ocean?

Through sampling survey, scientists found that marine life there is difficult to survive because the seawater is polluted by hydrogen sulfide and lacks oxygen. In the convection between the Black Sea and the Mediterranean Sea, the Black Sea lost its fresh seawater to its "neighbors" through the surface layer, in exchange for salty and heavy water flowing from the depths. Coupled with the dispersion of seawater velocity in the Black Sea and the poor convection between the upper and lower layers, the sea area that has been polluted for many years will naturally become a "dead zone".

There are many important ports along the Black Sea, such as Odessa in Ukraine, burris in Bulgaria, constanta in Romania and Istanbul in Turkey. Summer is cool, autumn is warm, winter is short and spring is long, and the four seasons are pleasant. The coast of Crimea is a famous tourist and convalescent resort.