When the masses of Laurasia and Gondwana formed and disintegrated, these two mainlands were filled with the Tethyan Sea. The last form of the Mediterranean today was formed by the pressure of the north, which began at the end of the Cretaceous period about 65 million years ago and lasted until the end of the Miocene period 13 million years ago. This mass also formed the curved mountain ranges surrounding the present Mediterranean Sea, causing the sedimentary masses in the Tethyan Sea to compress, bend and swell.
The hydrology and water structure of the Mediterranean is under the influence of the high evaporation rate of the high temperature of the basin. The water structure lost by the Mediterranean is The rate of water lost by evaporation is higher than the rate of precipitation, which is the main reason for the high salinity rate. Temperature changes in the Mediterranean Basin are reflected in the waters. The Mediterranean climate is cool and rainy in winter, warm and dry in the summer has revealed an extraordinary vegetation.
The main vegetation in the dryest parts of the basin was formed by the post-glacial period forests leaving their places in the scrub vegetation. This vegetation, which consists of countless species, adapts to hot and dry summer months with its thin leaves that reduce evaporation. Region-specific, large tree species are conifers, olive and oak trees.
The majority of fish communities and shellfish living in the Atlantic Ocean live in the Mediterranean. Bottom fishes are coral, shield, tonguefish, whiting, rockfish. Predatory fishes; stingrays, sharks, scabbard, snake-fish. These characteristics, combined with the political complexity of the region, mean the management and protection of the coastal and marine environment will require multilateral environmental agreements and regulations, abided by at a supranational level.
This approach is essential to sustainable development in all nations bordering on bodies of water that extend beyond their boundaries. In order to be able to analyse the different environmental problems and issues that affect the Mediterranean marine and coastal ecosystems it is important to be aware of the natural characteristics of the Mediterranean Basin and have an overview of the major drivers in the Mediterranean region, including all economic sectors within the Mediterranean basin and specially those devoted to the exploitation of the coastal and marine natural resources.
This allows increased understanding of the overall interrelation between Mediterranean ecosystems and the human drivers. Numerous islands correspond to isolated tectonic blocks, the summits of submarine ridges, or the tips of undersea volcanoes. The largest islands are Sicily, Sardinia, Corsica, Cyprus, and Crete, and the major island groups include the Balearics off the coast of Spain and the Ionian, Cyclades, and Dodecanese islands off Greece.
Apart from the coastal plains and the deltaic zones of large rivers Ebro, Rhone, Po and Nile , the coastlines are mostly rimmed by mountain ranges. Only the coastal plains from eastern Tunisia to the Sinai Peninsula, bordered mainly by low-lying desert, are free of mountains. In fact, the highest reaches of the main mountain ranges generally mark the limit of the hydrographic basin that drains towards the Mediterranean Sea.
The Mediterranean Sea stretches from the Atlantic Ocean on the west to the Asian continent on the east, and separates Europe from Africa.
The basin expands up to 2. The Mediterranean has narrow continental shelves and a large area of open sea. Therefore, a large part of the Mediterranean basin can be classified as deep sea and includes some unusual features such as variation of temperatures from The coasts of the western Mediterranean, just as those of the eastern basin, have been subjected in recent geologic times to the uneven action of deposition and erosion. This action, together with the movements of the sea and the emergence and submergence of the land, resulted in a rich variety of types of coasts.
The Italian Adriatic coast, revealing the Apennines, is typical of an emerged coast. The granite coast of north eastern Sardinia and the Dalmatian coast where the eroded land surface has sunk, producing elongated islands parallel to the coast, are typical submerged coasts. The Mediterranean Sea is a semi-enclosed sea characterized by high salinities, temperatures and densities.
The net evaporation exceeds the precipitation, driving an anti-estuarine circulation through the Strait of Gibraltar, contributing to very low nutrient concentrations.
The Mediterranean Sea has an active overturning circulation, one shallow cell that communicates directly with the Atlantic Ocean, and two deep overturning cells, one in each of the two main basins Tanhua et al.
It acts like an ocean system in which several temporal and spatial scales basin, sub-basin and mesoscale interact to form a highly complex and variable circulation. It is one of the few locations in the world where deep convection and water mass formation take place. The Mediterranean is also an important marginal basin to the North Atlantic producing very saline waters, the outflow of which through the Strait of Gibraltar may play an indirect role in the deep circulation of the North Atlantic.
The Mediterranean hydrodynamics are driven by three layers of water masses: a surface layer, an intermediate layer, and a deep layer that sinks to the bottom.
The Mediterranean Sea receives from the rivers that flow into it only about one-third of the amount of water that it loses by evaporation. In consequence, there is a continuous inflow of surface water from the Atlantic Ocean. After passing through the Strait of Gibraltar, the main body of the incoming surface water flows eastward along the north coast of Africa. This current is the most constant component of the circulation of the Mediterranean.
It is most powerful in summer, when evaporation in the Mediterranean is at a maximum. The Mediterranean Sea experiences a typical Mediterranean climate with hot and dry summers and mild and rainy winters.
The Mediterranean Sea hosts numerous beautiful islands. Covering a total area of about 25, km 2 , the island of Sicily is the largest island in the Mediterranean Sea. The Mediterranean Sea basin was formed during the Late Triassic and the early Jurassic periods due to the convergence of the African and Eurasian plates. Geological evidence indicates that about 5. About 5. The Mediterranean Sea has been regarded as the birthplace of Western civilization.
Many ancient civilizations such as the Phoenicians, Ancient Greece, and the Roman Empire were located along the shores of the Mediterranean Sea.
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