Mediterranean Sea

The Mediterranean Sea (Latin Mare Mediterraneum, so German also is Mediterranean Sea, präzisierend European Mediterranean ) is a Mediterranean between Europe, Africa and Asia, a marginal sea of the Atlantic Ocean and because it has only a very narrow connection to the Atlantic Ocean with the Strait of Gibraltar, also an inland sea. In Arabic and Turkish, it is also called the " White Sea " ( البحر الأبيض / al -Bahr al - Abyad or Turkish: Akdeniz ).

Together with the inherent within these islands and the coastal regions of southern Europe, Western Asia and North Africa is the Mediterranean Sea to the Mediterranean, which has its own climate ( Mediterranean climate ) and is characterized by its own flora and fauna.

  • 3.1 Origin and development of the Mediterranean
  • 3.2 The Mediterranean as sedimentary basins
  • 4.1 subbasin
  • 4.2 Tide
  • 4.3 Salinity
  • 4.4 Impact of global warming

Geography

The area of the Mediterranean is about 2.5 million square kilometers and its volume 4.3 million km ³. In the Calypso Deep, it reaches a maximum depth of 5267 meters. The average water depth is about 1720 meters.

Demarcation

The European Mediterranean Sea, as most of mainlanders surrounded and separated from the Ocean Mediterranean between the three continents of Africa, Europe and Asia. It is counted among the marginal seas of the Atlantic Ocean.

In the west it is connected through the Straits of Gibraltar to the Atlantic Ocean, northeast of the Dardanelles, the Sea of ​​Marmara and the Bosphorus to the Black Sea and the South East over the Suez Canal (since 1869) with the Red Sea, an inland sea of the Indian Ocean.

Structure

The Mediterranean is strongly divided by own extension seas and bays, especially in the east and north.

In the depths of the sea divided into two distinct pools, a western and an eastern, which are separated by the seismically highly active threshold Tunisia - Italy. Here stands the Tyrrhenian basin still from a third, independent pool.

For the purposes of the natural structure of the Mediterranean is divided into a western and an eastern part:

  • Alboran Sea Strait of Gibraltar
  • Catalan sea
  • Gulf of Valencia
  • Sardinian sea
  • Gulf of Genoa
  • Gulf of Gabès ( Little Syrtis )
  • Gulf of Sidra ( Great Syrtis )
  • Aegean Sea ( Aegean) Ikarisches sea
  • Thracian sea
  • Thermaic Golf
  • Gulf of Malia
  • Saronic Gulf
  • Myrtoisches sea
  • Sea ​​Of Crete

Rare is the division into a western, central and eastern part. In this case, the marine areas are expected around the Italian peninsula to the central Mediterranean: Ligurian Sea, Tyrrhenian Sea, Strait of Sicily, the Gulf of Gabès ( Small Sirte ), Ionian Sea, Adriatic Sea.

Bordering States - Mediterranean countries

Clockwise Spain, France, Monaco, Italy, Malta, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Albania, Greece, Turkey, Cyprus, Syria, Lebanon, Israel, Egypt, Libya, Tunisia, Algeria and Morocco have a share in the Mediterranean coast.

Gibraltar and the two military bases of Akrotiri and Dhekelia in Cyprus are British territories, but not officially part of the United Kingdom. The Palestinian Authority, with the Gaza Strip share of the Mediterranean coast.

In the Mediterranean, the two terms Mediterranean country and Mediterranean country are almost equally important, because all the major countries of the Mediterranean to the coast have access. For the former, but still belong to the small European States Vatican City and San Marino, and, perhaps, Andorra and Macedonia.

Islands and coasts

For the Mediterranean, which is counted to the oceanic marginal seas, include numerous island groups and individual larger and smaller islands. Of area, the largest island of the Mediterranean, Sicily is followed by Sardinia, which as Sicily is a region of Italy. More geographically large Mediterranean islands are - by size in descending order - Cyprus, Corsica and Crete. Cyprus and Malta with its neighboring islands make up the only two island countries of the Mediterranean. Sicily is the most populous island in the Mediterranean with more than five million people, by far.

Major island groups in the European Mediterranean

The major island groups in the European Mediterranean are from west to east

  • The Balearic Islands with the main island of Mallorca
  • Some groups of islands of Italy, the Tuscan Archipelago and the Lipari, Egadi and Pelagian Islands
  • Malta Gozo and several smaller islands
  • The islands of the lagoon of Venice
  • The Croatian islands, which are divided into groups of islands such as the Kornati
  • The Ionian Islands
  • The Aegean Islands, which are themselves divided into smaller groups of islands, for example, the Cyclades, Sporades, Saronic and the North Aegean islands

Larger peninsulas

On the west coast of the Mediterranean, the Iberian Peninsula with Spain and Portugal, which is bordered on the north and west by the Atlantic Ocean and is connected with France through the Pyrenees mountains in the northeast. East follows the boot-shaped peninsular with the bulk of Italy. The differently defined in extent Balkan peninsula between the Adriatic Sea, Aegean Sea and the Black Sea comprises the bulk of southeastern Europe. Also Asia Minor is sometimes seen as a peninsula between the Black and Mediterranean.

Considerably smaller dimensions are peninsulas such as Calabria and Salento in southern Italy, Istria in Croatia ( the largest peninsula in the Adriatic), the Peloponnese, Attica and Chalkidiki in Greece or the Gallipoli peninsula in European part of Turkey. The peninsulas of Cap Bon are on the far less indented southern coast of the Mediterranean Sea in Tunisia and Cyrenaica in Libya.

Coastline

The coasts lie along the characteristic metropolitan areas in the Mediterranean region, in terms of the land mass, namely Iberian Peninsula, French Mediterranean coast, the Apennine Peninsula, the Balkan Peninsula, Greece ( as a peninsula of the Balkans ), Asia Minor, Levant ( Middle East), Maghreb ( North Africa ), where the latter space the entire southern half of the coast occupies, but much less is structured, because only a mountain mass coastline determining the Atlas Mountains.

Well-known coastal sections:

Cities and metropolitan areas

Inflows

In the Mediterranean or in its marginal seas include the following rivers and streams flow with a length of over 200 kilometers:

In addition the excess water of the Black Sea via the Bosphorus and the Marmara Sea.

History

The Assyrians was the Mediterranean since Tiglath- pileser III. known, they called it the "Upper Sea sunset " or simply the upper ocean. In ancient times, the Mediterranean Sea was called by the Romans Mare Nostrum, which means our sea, as the Roman Empire ( Imperium Romanum) temporarily encircled the entire Mediterranean.

Geology

Formation and evolution of the Mediterranean

The European Mediterranean is largely a remnant of the Tethys, a large golf -like primeval ocean, surrounded by the supercontinent Pangea. The formation of the Mediterranean began with the breakup of Pangea and the drift of the African plate (then still part of the great Südkontinentes Gondwana ) to the south during the Triassic and Jurassic. As a result, the Tethys opened like a zipper to the west. The further north drift of the now dissolved out of the Gondwana Association African plate in the Cretaceous and their collision with the southern edge of Europe during the Tertiary led to the progressive restriction of the western Tethys or to alpidic orogeny. The creation of numerous of the Alps and the Carpathian arch divided the western Tethys in a northern part of the Paratethys, and a southern part, which developed into the present Mediterranean Sea ( the eastern Tethys closed in the wake of the North drift of India, by the same time the Indian Ocean was created ). The collision of Africa (including the Arab Peninsula ) to the southwest edge of the then Asia in the middle Miocene led to the isolation of the Mediterranean from the Indian Ocean. The formation of the young fold mountains of the Mediterranean and the islands as well as the distribution of shelf areas and deep-sea basins are the result of complex tectonic and geomorphic processes that are not yet fully understood. The oceanic crust preserved in the Eastern Mediterranean Western Tethysbeckens is the oldest in the world with an age of some 300 million years.

About six million years ago, in the Messinian (uppermost Miocene ) began the Mediterranean Sea dry out. Before the Messinian the Mediterranean was not across the narrow Strait of Gibraltar connected to the Atlantic Ocean, but over much wider arms of the sea, which on the one hand, via southern Spain, on the other hand, south of the Atlas Mountains led. As a result of plattentektonisch related collision of Africa with Southern Europe joined these marine compounds. Through the interplay of oceanographic isolation of the Mediterranean Basin and the arid climate in the region, the sea water evaporates rapidly and the level dropped. The forming salt desert is now documented in the seabed of the Mediterranean Sea in the form of powerful gypsum and salt deposits. Some millennia later, the Mediterranean basin was filled by water flowing from the Atlantic Ocean via the Strait of Gibraltar again. This process played probably more than once before six to five million years ago. The repeated evaporation explains the high thickness of the salt stock. The entire period is known as the Messinian Salinity Crisis (MSC).

The Messinian salinity crisis resulted in a Faunenschnitt in the Mediterranean, by which Charles Lyell already, without cause to know the geological limit stipulated by the Miocene to Pliocene. In the Miocene in the Mediterranean passed large groups of islands, some with land connections with North Africa. These were partially populated with tropical African Fauna: Old World monkeys ( Oreopithecus bambolii ), elephants ( Sicilian dwarf elephant), giraffes, hippos, crocodiles. In this Pliocene fauna has been largely replaced by immigration from Europe, eg by saber-toothed cats ( Machairodus and Metailurus ).

In periglacial the Würm or Vistula glaciation, the water level of the Mediterranean Sea was about 120 meters lower than today. Thus, the upper end of the Adriatic Sea was (caput Adrià ) mainland, many Greek islands were connected with Anatolia, Sardinia and Corsica formed a large island, as well as Sicily and Malta. East of Tunisia stretched a wide coastal plain. Before today's opening of Rhone, Nile, Ebro and vast plains were. The entrance of the Henry Cosquer cave with prehistoric rock paintings is now 36 m below sea level. The glazioeustatische sea level rise at the end of the Pleistocene was about 0.2 cm / a

In the early Holocene, the water level was about 35 meters lower than today. The barrier to the Black Sea was flooded around 5600 BC.

The Mediterranean as sedimentary basins

The sedimentary history of the Mediterranean is closely linked with the emergence of young fold mountains of the Mediterranean. The latter are important source areas for the sediments and associated with the orogeny tectonic processes were an important factor influencing the Sedimentationsdynamik. Large rivers such as the Ebro, Po and Rhone were and are important transport media for the sediments. The largest river system that empties into the Mediterranean, the Nile. He transported per year, about 60 million tons of sediment to the eastern Mediterranean. But not to be underestimated is also the entry of sediments from the adjacent desert areas (especially the Sahara) by wind.

A remarkable feature of the Mediterranean sedimentary sequence of the Pliocene and Quaternary is the rhythmic occurrence of sapropel deposits. Responsible for climate variations with weakening of aridity in the region could be. The existence and non-existence of links with the Atlantic and Indian Ocean ( the Arabian Gulf ) were also of great importance for the sedimentary evolution of the Mediterranean region - in particular with regard to the formation of evaporites.

Oceanography

Subbasin

The Mediterranean is mainly composed of four larger, backed by oceanic crust deep-sea basins: the Balearic Basin, also Algerian - Provencal basin, which is up to 3255 m deep and is located in the western part of the Mediterranean, is the smallest pool. In the western central part of the Tyrrhenian basin is located in the Tyrrhenian Sea, with a depth of up to 3758 m. In the eastern central part of the Mediterranean lies the Ionian basin in the Ionian Sea, the Calypso Deep - is up to 5267 m deep - the deepest point of the European Mediterranean. In the eastern region of the up to 4517 m deep Levantine basin is located in the Levantine Sea.

Tides

As the Mediterranean has only a narrow connection with the Atlantic Ocean and is only 3500 km long, it has little tidal range. The highest values ​​for the maximum tidal range in the range 100 cm (Venice ), 120 cm ( Trieste) and 200 cm (Gulf of Gabes ). But wide areas of the Mediterranean Sea have a barely detectable tidal range of less than 10 cm, only a few regions achieved by resonance values ​​of about 30 cm.

An appreciable tidal current is only available at the Strait of Gibraltar and in the lagoons between Venice and Trieste.

Salinity

The salinity of the European Mediterranean is approximately 3.8% higher than that of the Atlantic. This is a consequence of the strong evaporation, which is not compensated by the freshwater input of the big rivers and streams ( one speaks in this context of a concentration basin). Therefore, flows at the bottom of the Strait of Gibraltar as a strong salt water flow into the Atlantic Ocean while on the surface of a less saline according to net water loss even stronger counter- flow and therefore transported easier ocean waters in the Mediterranean Sea. The surface salinity increases from west to east, from 3.63% in the Strait of Gibraltar to 3.91 % off the coast of Asia Minor.

Effects of global warming

The Mediterranean Sea is strongly affected by the global warming. So researchers recorded since the mid-20th century, sea level rise, which has accelerated since the 1970s up to 2.5 to 10 millimeters per year between 1990 and 2007. Also, the water temperature since the 1970s increased by 0.12 to 0.5 ° C significantly.

Flora and Fauna

The fauna of the Mediterranean is very diverse and rich in species. It consists primarily of fish, sponges, cnidarians, molluscs, echinoderms and arthropods. According to estimates come in the Mediterranean about 700 species of fish. In the Mediterranean, 35 species of sharks have been detected so far. Among them are like the great white shark, blue sharks and shortfin mako for humans potentially dangerous species. However, the population density of this species is very low, which is probably the main reason that shark attacks are extremely rare in the Mediterranean. Most common are harmless species, such as the Kleingefleckte dogfish.

Even whales are found in the Mediterranean. It could already be detected by baleen whales, five species. In the Mediterranean, the fin whale is the only baleen whale, which is regularly observed. So far, 16 species of toothed whales were detected. Among them are the Common dolphin, the bottlenose dolphins, pilot whales and sperm whales. The most common whales and dolphins are observed in the Strait of Gibraltar and in the Ligurian Sea; especially the dolphins are located but in the whole Mediterranean.

The only species of seal in the Mediterranean Sea, the Mediterranean monk seal. She is threatened with extinction.

The most important and at the same time Gefäßpflanzenart most common in the Mediterranean is the Neptune grass.

Negative impact of man

The ecosystem of the Mediterranean is threatened by overfishing. It is among the most exploited marine regions of the world. Some fish species have already disappeared, according to Greenpeace. Especially the tuna and swordfish are threatened by the high demand.

As part of the 2006 Lebanon war, there was a devastating oil spill in the eastern Mediterranean.

A threat with hardly überschätzendem impact on the ecosystem in the Mediterranean represents the devastating spread of the alga Caulerpa taxifolia entrained, which has begun to overgrow the typical seagrass beds, which are responsible for the productivity of the Mediterranean is of great importance.

Other anthropogenic impacts on the ecosystem of the Mediterranean Sea are:

  • The Lessepssche migration through the Suez Canal
  • The accelerated salinization by Dumping of salts from seawater desalination plants and
  • By decreasing the freshwater inflow due to the ever increasing water needs of the population in the catchment area

Climate

The Mediterranean climate is characterized by very hot, mostly dry summers and rainy rich and mild winters. The mean air temperatures range in summer from 23 ° C in the western regions to 26 ° C in the east. Maximum temperatures are 30 ° C. In winter, the values ​​are at 10 ° C in the west and 16 ° C prior to the Levantine coast. The annual precipitation increases from west to east.

Almost the entire summer prevail under the influence of the subtropical high pressure belt before weather resistant layers; only in the eastern Mediterranean (especially in the Aegean Sea ) lead the waving from the north Etesian to cooling. In winter, especially the western part of the Mediterranean is under the influence of westerly circulation (see wind).

From the north, advancing storm force winds such as the Mistral in southern France, cause sometimes striking surges of cold air. The Bora ( Bura Croatian ) is a dry, cold and gusty fall wind on the Croatian Adriatic coast. Winds from Bora type include with their frequency and their high average speeds ( in winter), on the coast of Croatia among the strongest in the world.

Libyan Sea Gulf of Lion Icarian Sea Malian Gulf Myrtoan Sea Venetian Lagoon List of islands of Croatia Saronic Islands Andalusia Nile Delta Achelous River Arno Aude (river) Ceyhan River Chelif River Adige Gediz River Moulouya River Orontes River Piave (river) Reno (river) Tiber Turia River History of the Mediterranean region Classical antiquity Desert climate Tidal resonance Small-spotted catshark Posidonia oceanica List of fish of the Mediterranean Sea Lessepsian migration Aswan Dam Eutrophication Atlantropa Digital Object Identifier Fernand Braudel Integrated Authority File
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