Situated in Asia between the northern coast of Turkey and the southern coast of The Ukraine,The Black Sea is connected to the oceanic system by way of the 61 km long ( 38 miles ) Dardanelles Strait and the Bosphoros SeaÂ by way ofÂ the Aegean Sea,a region of the Mediterranean Sea, whichÂ flows into the Atlantic Ocean.
The Black Sea has a surface area of 436,400 square kilometres ( 168,500 miles ) a coastline of about 8,000 km ( 5,000 miles )Â and a depth of 2,206 metres ( 7,238 ft ).
It is fed by a fluvial system of several rivers, the largest of which are The Don, The Dnieper and The Danube.
The Kerch Straits on it's northern shore with The Ukraine connects The Black Sea with the Sea of Azov.
The Black Sea'sÂ sea bedÂ was formed by way of the uplift of the Caucasus, Pontides and Balkan mountain ranges, after the collision of the Eurasian and African tectonic plates, 5 - 12 million years ago. This upliftÂ caused a vast,Â low lyingÂ valley.Â
Eight thousand, five hundred years ago, global warming causedÂ ice caps in Northern Canada to melt, which causedÂ the sea level of the Atlantic Ocean to rise dramatically. The billions of gallons of water which flowed into the Atlantic during this periodÂ went on to furtherÂ swell the waters of the Mediterranean Sea, whichÂ in turnÂ went on toÂ flood this low lying valley intoÂ the area of water we knowÂ today as theÂ Black Sea.Â The formation of the Black Sea was caused by the same phenomena andÂ around the same time that the Bosphorous Sea was formed andÂ Great BritainÂ became seperated from the rest of Europe.Â Â Â Â Â
The name Black Sea comes from the Ottoman Turkish word Kara, and although this does infact mean black in modern Turkish, actually meant ' North ' in the old medieval language.
In the time of the ancient Greeks, the sea was known as ' Euxeinos Pontos ' the Hospitable Sea ' and in Roman times was known as Mar Maggiore, the ' Large Sea '.
It's modern names from each of it's bordering countries are :
Cherno More - Bulgarian.
Chorne More - Ukrainian.
Chornoye More - Russian.
Kara Deniz - Turkish.
Marea Neagra - Rumanian.
Shavi Zghva - Georgian.
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This picture shows the Black Sea's shallow perimeter, along withÂ waves caused byÂ a cyclonic gyre, and it's larger, deeper main basin.
The Black Sea is the world's largest meromictic basin, which means that it's layers of water do not mix.
This leads to the sea having anoxic water, meaning it's water is depleted of dissolved oxygen.
Oxygen is prevented from reaching it's deeper water levels by a pronounced density stratification, a condition that occurs when the rate of oxidation of organic matter is greater than the supply of dissolved oxygen.
The Black Sea's deeper water levels are fed by the warm, salty waters of the Mediterranean sea and have a salinity level of around 22 parts per thousand,whereas it's upper levels are cooler and less saline with a salinity level of around 18 parts per thousand.
This occurs by way of a cyclonic gyre, a rotating ocean current, along it's outer shelf, or perimeter. This phenonema helps support an active marine eco - system dominated by brackish water lovers such as Sea Horses, Stingrays andÂ Spiny DogfishÂ as well as a large colony ofÂ Phytoplankton.Â
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Phytoplankton is a component of plankton that lives on the well lit surface layer of the Black Sea.It is an organism that produces complex organic compounds and when it finds it's self in favourable conditions, can lead to vastÂ colonies of it.
The phytoplankton is a problem as it's growth and decay consumes all the available oxygen in the water, leading to large dead areas where fish and plants can not survive.
Phytoplankton accounts for half of the photosynthetic activity on earth.
The above picture shows a large blue ring of phytoplankton circling the outer, shallowÂ perimeter of the Black Sea. Growth of the phytoplanktonÂ isÂ aided by way of sediment flowing intoÂ the Black SeaÂ from it's vast network of rivers, which contain silt and more importantly, fertiliser from agricultural run off, which feeds the phytoplankton. This can be seen as the large green area to the top left of the aboveÂ picture, as sediment runs from the mouth of the River Danube.
The area is also of great interest to marine archaeologists, as shipwrecks have been found in it's waters in an excellent state of preservation.
The Black Sea is surrounded by heavilly built up industrial areas and large sea ports. it also has a thriving tourist industry on it's Bulgarian, Turkish and Ukrainian coasts.It's two major cities areÂ Odessa, the capital of The Ukraine and Istanbul, Turkey's largest city.
The whole area experiences warm, dry Summers, with cold, dry Winters on it's northern coast and cold, wet Winters on it's southern coast.
Localised industrial pollution and heavy precipitation lead to dense cloud cover over much of it's southern coast during the Winter months.
The Black Sea is bordered by 6 countries including the Ukrainian Autonomous Republic of Crimea on the Crimean Peninsula, they are :
The Black Sea is home to 10 small islands, they are:
St Anastasia - Bulgaria.
Berezan - Turkey.
St Cyricus - Bulgaria.
Dzharylgach - Ukraine.
Giresun - Turkey.
St Ivan - Bulgaria.
St Peter - Bulgaria.
Sacalin - Rumania.
Snake - Rumania.
St Thomas - Bulgaria.
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