Is the Caspian Sea saltwater?
19653787#8
The Caspian Sea, like the Black Sea, Namak Lake, and Lake Urmia, is a remnant of the ancient Paratethys Sea. It became landlocked about 5.5 million years ago due to tectonic uplift and a fall in sea level. During warm and dry climatic periods, the landlocked sea almost dried up, depositing evaporitic sediments like halite that were covered by wind-blown deposits and were sealed off as an evaporite sink when cool, wet climates refilled the basin. (Comparable evaporite beds underlie the Mediterranean.) Due to the current inflow of fresh water, the Caspian Sea is a freshwater lake in its northern portions, and is most saline on the Iranian shore, where the catchment basin contributes little flow. Currently, the mean salinity of the Caspian is one third that of Earth's oceans. The Garabogazköl embayment, which dried up when water flow from the main body of the Caspian was blocked in the 1980s but has since been restored, routinely exceeds oceanic salinity by a factor of 10.
Caspian Sea
19653787#2
The sea has a surface area of 371,000 km (143,200 sq mi) (not including the detached lagoon of Garabogazköl) and a volume of 78,200 km(18,800 cu mi). It has a salinity of approximately 1.2% (12 g/l), about a third of the salinity of most seawater.
Caspian Sea
19653787#21
The Caspian turtle ("Mauremys caspica"), although found in neighboring areas, is a wholly freshwater species. The zebra mussel is native to the Caspian and Black Sea basins, but has become an invasive species elsewhere, when introduced. The area has given its name to several species, including the Caspian gull and the Caspian tern. The Caspian seal ("Pusa caspica") is the only aquatic mammal and is endemic to the Caspian Sea, being one of very few seal species that live in inland waters, but it is different from the those inhabiting freshwaters due to the hydrological environment of the sea.
Caspian Sea
49319487#0
The Black Sea-Caspian Steppe is an informal name for that part of the Eurasian Steppe that extends south between the Black and Caspian Seas. It is usually treated as part of the Pontic-Caspian steppe which includes the area north of the Black and Caspian Seas, but there is some reason to treat it as a distinct place. Its natural boundaries are the Sea of Azov and Black Sea on the west, the Caucasus Mountains on the south and the Caspian Sea on the east. Its northern boundary may be taken as the triangle formed by the lower Don River and Volga River which are about 60 km apart to the west of Volgograd. This article excludes the north slope of the Caucasus which is not steppe and has a distinct geography and history.
Black Sea–Caspian Steppe
19653787#0
The Caspian Sea is the world's largest inland body of water, variously classed as the world's largest lake or a full-fledged sea. It is an endorheic basin (a basin without outflows) located between Europe and Asia, to the east of the Caucasus Mountains and to the west of the broad steppe of Central Asia. It is bounded by Kazakhstan to the northeast, Russia to the northwest, Azerbaijan to the west, Iran to the south, and Turkmenistan to the southeast. The Caspian Sea is home to a wide range of species and may be best known for its caviar and oil industries. Pollution from the oil industry and dams on rivers draining into the Caspian Sea have had negative effects on the organisms living in the sea.
Caspian Sea
349764#7
The lower part of the river flows through the Kura-Aras Lowland, which covers most of central Azerbaijan and abuts the Caspian Sea. The Kura is the third largest, after the Volga and Ural, of the rivers that flow into the Caspian. Its delta is the fourth largest among the rivers that flow into the Caspian Sea, and is divided into three main sections, or "sleeves", composed of sediment the river deposited during different periods of time. Before 1998, the river flowed all the way to the tip of the delta, where it discharged into the Caspian. In that year, the river escaped its channel and started to flow off to the west, leaving the last few kilometers abandoned. The course change is believed to be the result of a rise in the level of the Caspian Sea coupled with a major flood of the Kura.
Kura (Caspian Sea)
19653787#10
Differences between the three regions are dramatic. The Northern Caspian only includes the Caspian shelf, and is very shallow; it accounts for less than 1% of the total water volume with an average depth of only . The sea noticeably drops off towards the Middle Caspian, where the average depth is . The Southern Caspian is the deepest, with oceanic depths of over , greatly exceeding the depth of other regional seas, such as the Persian Gulf. The Middle and Southern Caspian account for 33% and 66% of the total water volume, respectively. The northern portion of the Caspian Sea typically freezes in the winter, and in the coldest winters ice forms in the south as well.
Caspian Sea
19653787#13
The Caspian has characteristics common to both seas and lakes. It is often listed as the world's largest lake, although it is not a freshwater lake. It contains about 3.5 times more water, by volume, than all five of North America's Great Lakes combined. The Caspian was once part of the Tethys Ocean, but became landlocked about 5.5 million years ago due to plate tectonics. The Volga River (about 80% of the inflow) and the Ural River discharge into the Caspian Sea, but it has no natural outflow other than by evaporation. Thus the Caspian ecosystem is a closed basin, with its own sea level history that is independent of the eustatic level of the world's oceans.
Caspian Sea
19653787#22
Archeological studies of Gobustan petroglyphs indicate that there once had been dolphins and porpoises, or a certain species of beaked whales and a whaling scene indicates large baleen whales likely being present in Caspian Sea at least until when the Caspian Sea ceased being a part of the ocean system or until the Quaternary or much more recent periods such as until the last glacial period or antiquity. Although the rock art on Kichikdash Mountain is assumed to be of a dolphin or of a beaked whale, it might instead represent the famous beluga sturgeon due to its size (430 cm in length), but fossil records suggest certain ancestors of modern dolphins and whales, such as "Macrokentriodon morani" (bottlenose dolphins) and "Balaenoptera sibbaldina" (blue whales) were presumably larger than their present descendants. From the same artworks, auks, like Brunnich's Guillemot could also have been in the sea as well, and these petroglyphs suggest marine inflow between the current Caspian Sea and the Arctic Ocean or North Sea, or the Black Sea. This is supported by the existences of current endemic, oceanic species such as lagoon cockles which was genetically identified to originate in Caspian/Black Seas regions.
Caspian Sea
19653787#47
, negotiations related to the demarcation of the Caspian Sea had been going on for nearly a decade among the states bordering the Caspian – Azerbaijan, Russia, Kazakhstan, Turkmenistan, and Iran. The status of the Caspian Sea is the key problem. Access to mineral resources (oil and natural gas), access for fishing, and access to international waters (through Russia's Volga river and the canals connecting it to the Black Sea and Baltic Sea) all depend upon the outcomes of negotiations. Access to the Volga River is particularly important for the landlocked states of Azerbaijan, Kazakhstan, and Turkmenistan. This concerns Russia, because the potential traffic would use its inland waterways. If a body of water is labelled as a sea, then there would be some precedents and international treaties obliging the granting of access permits to foreign vessels. If a body of water is labelled merely as a lake, then there are no such obligations. Environmental issues are also somewhat connected to the status and borders issue.
Caspian Sea
19653787#3
The word Caspian is derived from the name of the Caspi, an ancient people who lived to the southwest of the sea in Transcaucasia. Strabo wrote that "to the country of the Albanians belongs also the territory called Caspiane, which was named after the Caspian tribe, as was also the sea; but the tribe has now disappeared". Moreover, the Caspian Gates, which is the name of a region in Iran's Tehran province, possibly indicates that they migrated to the south of the sea. The Iranian city of Qazvin shares the root of its name with that of the sea. In fact, the traditional Arabic name for the sea itself is Baḥr al-Qazwin (Sea of Qazvin).
Caspian Sea