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5 novembre 2011 6 05 /11 /novembre /2011 10:20

The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant. The sea is sometimes considered a part of the Atlantic Ocean, although it is usually identified as a completely separate body of water.Sony VAIO VGN-FW190ECH Battery

The name Mediterranean is derived from the Latin mediterraneus, meaning "inland" or "in the middle of the earth" (from medius, "middle" and terra, "earth"). It covers an approximate area of 2.5 million km² (965,000 sq mi), but its connection to the Atlantic (the Strait of Gibraltar) is only 14 km (8.7 mi) wide. Sony VAIO VGN-FW190EDH Battery

In oceanography, it is sometimes called the Eurafrican Mediterranean Sea or the European Mediterranean Sea to distinguish it from mediterranean seas elsewhere.

The Mediterranean Sea has an average depth of 1,500 m (4,900 ft) and the deepest recorded point is 5,267 m (17,280 ft) in theCalypso Deep in the Ionian Sea.Sony VAIO VGN-FW190NAH Battery

It was an important route for merchants and travelers of ancient times that allowed for trade and cultural exchange between emergent peoples of the region — the Mesopotamian, Persian, Egyptian, Phoenician, Carthaginian, Iberian, Greek and Byzantine,Roman and Italian, Illyrian, Thracian, Levantine, Gallic, Armenian, Arabic, Berber, Jewish, Aragonese, Slavic and Turkishcultures.Sony VAIO VGN-FW190NBH Battery

The history of the Mediterranean region is crucial to understanding the origins and development of many modern societies. "For the three quarters of the globe, the Mediterranean Sea is similarly the uniting element and the centre of World History."Sony VAIO VGN-FW190NCH Battery

Name

The term Mediterranean derives from the Latin word mediterraneus, meaning "in the middle of earth" or "between lands" (medius, "middle, between" + terra, "land, earth"). This is on account of the sea's intermediary position between the continents of Africa and Europe.Sony VAIO VGN-FW190NDH Battery

The Greek name Mesogeios (?????????), is similarly from ????, "middle" + ??, "land, earth").

The Mediterranean Sea has been known by a number of alternative names throughout human history. For example the Romans commonly called it Mare Nostrum (Latin, "Our Sea"), and occasionally Mare Internum (Sallust, Jug. 17).Sony VAIO VGN-FW190NEH Battery

In the Bible, it was primarily known as the "Great Sea" (Num. 34:6,7; Josh. 1:4, 9:1, 15:47; Ezek. 47:10,15,20), or simply "The Sea" (1 Kings 5:9; comp. 1 Macc.14:34, 15:11); however, it has also been called the "Hinder Sea", due to its location on the west coast of the Holy Land, and therefore behind a person facing the east, as referenced in the Old Testament, Sony VAIO VGN-FW198U/H Battery

sometimes translated as "Western Sea", (Deut. 11:24; Joel 2:20). Another name was the "Sea of the Philistines" (Exod.23:31), from the people occupying a large portion of its shores near the Israelites.

In Modern Hebrew, it has been called HaYyam HaTtikhon (?????? ??????????), "the middle sea", a literal adaptation of the German equivalent Mittelmeer.Sony VAIO VGN-FW260J/B Battery

InTurkish, it is known as Akdeniz, "the white sea". In modern Arabic, it is known as al-Ba?r al-Abya? al-Mutawassi? (????? ?????? ???????), "the White Middle Sea," while in Islamic and older Arabic literature, it was referenced as Ba?r al-R?m (??? ?????), or "the Roman/Byzantine Sea."Sony VAIO VGN-FW280J/H Battery

History

As a sea around which some of the most ancient human civilisations were arranged, it has had a major influence on the history and ways of life of these cultures. It provided a way of trade, colonisation and war, and was the basis of life (via fishing and the gathering of other seafood) for numerous communities throughout the ages.Sony VAIO VGN-FW290JRB Battery

The combination of similarly shared climate, geology and access to a common sea has led to numerous historical and cultural connections between the ancient and modern societies around the Mediterranean.

Two of the most notable Mediterranean civilisations in classical antiquity were the Greek city states and the Phoenicians.Sony VAIO VGN-FW290JTB Battery

When Augustus founded the Roman Empire, the Mediterranean sea began to be called Mare Nostrum (literally:"Our Sea") by the Romans.

Darius I of Persia, who conquered Ancient Egypt built a canal linking Mediterranean to the Red Sea. Darius's canal was wide enough that two triremes could pass each other with oars extended, and required four days to traverse.Sony VAIO VGN-FW290JTH Battery

The Roman empire began to crumble, however, in the fifth century and Rome collapsed after 476 AD. Temporarily the east was again dominant as the Byzantine Empire formed from the eastern half of the Roman one. Another power was rising in the east, that of Islam. At its greatest extent, the Arab Empire controlled 3/4 of the Mediterranean region.Sony VAIO VGN-FW290JTW Battery

Europe was reviving, however, as more organized and centralised states began to form in the later Middle Ages after the Renaissance of the 12th century.

Ottoman power continued to grow, and in 1453, the Byzantine Empire was extinguished with the fall of Constantinople. Sony VAIO VGN-FW355J/H Battery

The growing naval prowess of the European powers confronted further rapid Ottoman expansion in the region when the Battle of Lepanto checked the power of the Ottoman navy. The development of oceanic shipping began to affect the entire Mediterranean, however.Sony VAIO VGN-FW373J/B Battery

While once all trade from the east had passed through the region, the circumnavigation of Africa allowed spices and other goods to be imported directly to the Atlantic ports of western Europe.

Geography

he Mediterranean Sea is connected to the Atlantic Ocean by the Strait of Gibraltar on the west and to the Sea of Marmara and theBlack Sea, by the Dardanelles and the Bosporus respectively, on the east. Sony VAIO VGN-FW30B Battery

The Sea of Marmara is often considered a part of the Mediterranean Sea, whereas the Black Sea is generally not. The 163 km (101 mi) long man-made Suez Canal in the southeast connects the Mediterranean Sea to the Red Sea.Sony VAIO VGN-FW50B Battery

Large islands in the Mediterranean include Cyprus, Crete, Euboea, Rhodes, Lesbos, Chios, Kefalonia, Corfu, Naxos and Andros in theeastern Mediterranean; Sardinia, Corsica, Sicily, Cres, Krk, Bra?, Hvar, Pag, Kor?ula and Malta in the central Mediterranean; andIbiza, Majorca and Minorca (the Balearic Islands) in the western Mediterranean.Sony VAIO VGN-FW51B/W Battery

The climate is a typical Mediterranean climate with hot, dry summers and mild, rainy winters. Crops of the region include olives,grapes, oranges, tangerines, and cork.

Extent

The International Hydrographic Organization defines the limits of the Mediterranean Sea as follows:Sony VAIO VGN-FW51MF Battery

The Mediterranean Sea is bounded by the coasts of Europe, Africa and Asia, from the Strait of Gibraltar on the West to the entrances to the Dardanelles and the Suez Canal on the East.

It is divided into two deep basins as follows: Sony VAIO VGN-FW51MF/H Battery

Western Basin

On the West. A line joining the extremities of Cape Trafalgar (Spain) and Cape Spartel (Africa).

On the Northeast. The West Coast of Italy. In the Strait of Messina a line joining the North extreme of Cape Paci (15°42'E) with Cape Peloro, the East extreme of the Island of Sicily. The North Coast of Sicily.Sony VAIO VGN-FW51ZF Battery

On the East. A line joining Cape Lilibeo the Western point of Sicily (17px-WMA_button2b.png37°47?N 12°22?E), through the Adventure Bank toCape Bon (Tunisia).

Eastern Basin

On the West. The Northeastern and Eastern limits of the Western Basin. Sony VAIO VGN-FW51ZF/H Battery

On the Northeast. A line joining Kum Kale (26°11'E) and Cape Helles, the Western entrance to the Dardanelles.

On the Southeast. The entrance to the Suez Canal.

On the East. The coasts of Syria and Palestine.  Sony VAIO VGN-FW52JB Battery

(It should be noted that the coast referred to as belonging to Palestine in this document dating to 1953 has been within the internationally recognised borders of the country known as Israel since 1948. Of the territories administered by the Palestinian Authority, only the Gaza Strip has a sea coast.)Sony VAIO VGN-FW54FB Battery

Oceanography

Being nearly landlocked affects the Mediterranean Sea's properties; for instance, tides are very limited as a result of the narrow connection with the Atlantic Ocean. The Mediterranean is characterized and immediately recognised by its deep blue colour.Sony VAIO VGN-FW70DB Battery

Evaporation greatly exceeds precipitation and river runoff in the Mediterranean, a fact that is central to the water circulation within the basin. Evaporation is especially high in its eastern half, causing the water level to decrease and salinity to increase eastward.Sony VAIO VGN-FW71DB/W Battery

This pressure gradient pushes relatively cool, low-salinity water from the Atlantic across the basin; it warms and becomes saltier as it travels east, then sinks in the region of the Levant and circulates westward, to spill over the Strait of Gibraltar.Thus, seawater flow is eastward in the Strait's surface waters, and westward below; once in the Atlantic, this chemically distinct Mediterranean Intermediate Water can persist thousands of kilometres away from its source.Sony VAIO VGN-FW72JGB Battery

Geology

The geologic history of the Mediterranean is complex. It was involved in the tectonic break-up and then collision of the African and Eurasian plates. The Messinian Salinity Crisis occurred in the late Miocene (12 million years ago to 5 million years ago) when the Mediterranean dried up. Geologically the Mediterranean is underlain by oceanic crust.Sony VAIO VGN-FW73JGB Battery

The Mediterranean Sea has an average depth of 1,500 m (4,900 ft) and the deepest recorded point is 5,267 m (17,280 ft) in the Calypso Deep in the Ionian Sea. The coastline extends for 46,000 km (29,000 mi). A shallow submarine ridge (the Strait of Sicily) between the island of Sicily and the coast of Tunisia divides the sea in two main subregions Sony VAIO VGN-FW74FB Battery

(which in turn are divided into subdivisions), the Western Mediterranean and the Eastern Mediterranean. The Western Mediterranean covers an area of about 0.85 million km² (0.33 million mi²) and theEastern Mediterranean about 1.65 million km² (0.64 million mi²).Sony VAIO VGN-FW81HS Battery

Tectonic evolution

The geodynamic evolution of the Mediterranean Sea was provided by the convergence of European and African plates. This process was driven by the differential spreading along the Atlantic ridge, which led to the closure of the Tethys Ocean and eventually to the Alpine orogenesis. Sony VAIO VGN-FW81NS Battery

However, the Mediterranean also hosts wide extensional basins and migrating tectonic arcs, in response to its land-locked configuration.

According to a report published by Nature in 2009, scientists think that the Mediterranean Sea was mostly filled during a time period of less than two years, Sony VAIO VGN-FW81S Battery

in a major flood (the Zanclean flood) that happened approximately 5.33 million years ago, in which water poured in from the Atlantic Ocean and through the Strait of Gibraltar, at a rate three times the current flow of the Amazon River.

Eastern Mediterranean

In middle Miocene times, the collision between the Arabian microplate and Eurasia led to the separation between the Tethys and the Indian oceans. Sony VAIO VGN-FW82DS Battery

This process resulted in profound changes in the oceanic circulation patterns, which shifted global climates towards colder conditions. The Hellenic arc, which has a land-locked configuration, underwent a widespread extension for the last 20 Myr due to a slab roll-back process.Sony VAIO VGN-FW82JS Battery

In addition, the Hellenic Arc experienced a rapid rotation phase during the Pleistocene, with a counterclockwise component in its eastern portion and a clockwise trend in the western segment.

Central Mediterranean

The opening of small oceanic basins of the central Mediterranean follows a trench migration and back-arc opening process that occurred during the last 30 Myr. Sony VAIO VGN-FW82XS Battery

This phase was characterised by the anticlockwise rotation of the Corsica-Sardinia block, which lasted until the Langhian (ca.16 Ma), and was in turn followed by a slab detachment along the northern African margin. Subsequently, a shift of this active extentional deformation led to the opening of the Tyrrenian basin.Sony VAIO VGN-FW83DS Battery

Western Mediterranean

Since Mesozoic to Tertiary times, during convergence between Africa and Iberia, the Betic-Rif mountain belts developed. Tectonic models for its evolution include: rapid motion of Alboran microplate, subduction zone and radial extensional collapse caused by convective removal of lithospheric mantle.Sony VAIO VGN-FW83JS Battery

The development of these intramontane Betic and Rif basins led to the onset of two marine gateways which were progressively closed during the late Miocene by an interplay of tectonic and glacio-eustatic processes.

Paleoenvironmental analysis

Its semi-enclosed configuration makes the oceanic gateways critical in controlling circulation and environmental evolution in the Mediterranean Sea.Sony VAIO VGN-FW83XS Battery

Water circulation patterns are driven by a number of interactive factors, such as climate and bathymetry, which can lead to precipitation of evaporites. During late Miocene times, a so-called "Messinian Salinity Crisis" (MSC hereafter) occurred, which was triggered by the closure of the Atlantic gateway.Sony VAIO VGN-FW90HS Battery

Evaporites accumulated in the Red Sea Basin (late Miocene), in the Carpatian foredeep (middle Miocene) and in the whole Mediterranean area (Messinian). An accurate age estimate of the MSC—5.96 Ma—has recently been astronomically achieved; furthermore, this event seems to have occurred synchronously.Sony VAIO VGN-FW90NS Battery

The beginning of the MSC is supposed to have been of tectonic origin; however, an astronomical control (eccentricity) might also have been involved. In the Mediterranean basin, diatomites are regularly found underneath the evaporite deposits, thus suggesting (albeit not clearly so far) a connection between their geneses.Sony VAIO VGN-FW90S Battery

The present-day Atlantic gateway, i.e. the Strait of Gibraltar, finds its origin in the early Pliocene. However, two other connections between the Atlantic Ocean and the Mediterranean Sea existed in the past: theBetic Corridor (southern Spain) and the Rifian Corridor (northern Morocco). Sony VAIO VGN-FW91NS Battery

The former closed during Tortoniantimes, thus providing a "Tortonian Salinity Crisis" well before the MSC; the latter closed about 6 Ma, allowing exchanges in the mammal fauna between Africa and Europe. Nowadays, evaporation is more relevant than the water yield supplied by riverine water and precipitation, so that salinity in the Mediterranean is higher than in the Atlantic.Sony VAIO VGN-FW91S Battery

These conditions result in the outflow of warm saline Mediterranean deep water across Gibraltar, which is in turn counterbalanced by an inflow of a less saline surface current of cold oceanic water.

The Mediterranean was once thought to be the remnant of the Tethys Ocean. It is now known to be a structurally younger ocean basin known as Neotethys. Sony VAIO VGN-FW92DS Battery

The Neotethys formed during the Late Triassic and Early Jurassicrifting of the African and Eurasian plates.

Paleoclimate

Because of its latitudinal position and its land-locked configuration, the Mediterranean is especially sensitive to astronomically induced climatic variations, which are well documented in its sedimentary record. Sony VAIO VGN-FW92JS Battery

Since the Mediterranean is involved in the deposition of eolian dust from the Sahara during dry periods, whereas riverine detrital input prevails during wet ones, the Mediterranean marine sapropel-bearing sequences provide high-resolution climatic information.Sony VAIO VGN-FW93DS Battery

These data have been employed in reconstructing astronomically calibrated time scales for the last 9 Ma of the Earth's history, helping to constrain the time of pastGeomagnetic Reversals. Furthermore, the exceptional accuracy of these paleoclimatic records have improved our knowledge of the Earth's orbital variations in the past.Sony VAIO VGN-FW93JS Battery

Ecology and biota

As a result of the drying of the sea during the Messinian Salinity Crisis, the marine biota of the Mediterranean are derived primarily from the Atlantic Ocean. Sony VAIO VGN-FW93XS Battery

The North Atlantic is considerably colder and more nutrient-rich than the Mediterranean, and the marine life of the Mediterranean has had to adapt to its differing conditions in the five million years since the basin was reflooded.

The Alboran Sea is a transition zone between the two seas, containing a mix of Mediterranean and Atlantic species. Sony VAIO VGN-FW94FS Battery

The Alboran Sea has the largest population ofBottlenose Dolphins in the western Mediterranean, is home to the last population of harbour porpoises in the Mediterranean, and is the most important feeding grounds for Loggerhead Sea Turtles in Europe. The Alboran sea also hosts important commercial fisheries, including sardines and swordfish. Sony VAIO VGN-FW94GS Battery

In 2003, the World Wildlife Fundraised concerns about the widespread drift net fishing endangering populations of dolphins, turtles, and other marine animals.

Invasive species

The opening of the Suez Canal in 1869 created the first salt-water passage between the Mediterranean and Red Sea.Sony VAIO VGN-FW94HS Battery

The Red Sea is higher than the Eastern Mediterranean, so the canal serves as a tidal strait that pours Red Sea water into the Mediterranean. TheBitter Lakes, which are hyper-saline natural lakes that form part of the canal, blocked the migration of Red Sea species into the Mediterranean for many decades, Sony VAIO VGN-G118CN Battery

but as the salinity of the lakes gradually equalized with that of the Red Sea, the barrier to migration was removed, and plants and animals from the Red Sea have begun to colonise the Eastern Mediterranean. The Red Sea is generally saltier and more nutrient-poor than the Atlantic, so the Red Sea species have advantages over Atlantic species in the salty and nutrient-poor Eastern Mediterranean.Sony VAIO VGN-G118GN/B Battery

Accordingly, Red Sea species invade the Mediterranean biota, and not vice versa; this phenomenon is known as the Lessepsian migration (after Ferdinand de Lesseps, the French engineer) or Erythrean invasion. The construction of the Aswan High Dam across the Nile River in the 1960s reduced the inflow of freshwater and nutrient-rich silt from the Nile into the Eastern Mediterranean,Sony VAIO VGN-G118GN/T Battery

making conditions there even more like the Red Sea and worsening the impact of theinvasive species.

Invasive species have become a major component of the Mediterranean ecosystem and have serious impacts on the Mediterranean ecology, endangering many local and endemic Mediterranean species.Sony VAIO VGN-G118TN/B Battery

A first look at some groups of exotic species show that more than 70% of the non-indigenous decapods and about 63% of the exotic fishes occurring in the Mediterranean are of Indo Pacific origin, introduced into the Mediterranean through the Suez Canal. This makes the Canal as the first pathway of arrival of “alien” species into the Mediterranean. Sony VAIO VGN-G118TN/S Battery

The impacts of some lessepsian species have proven to be considerable mainly in the Levantine basin of the Mediterranean, where they are replacing native species and becoming a “familiar sight”.

According to the International Union for Conservation of Nature definition, as well as Convention on Biological Diversity(CBD) and Ramsar Convention terminologies, they are alien species, Sony VAIO VGN-G11VN/T Battery

as they are non-native (non-indigenous) to the Mediterranean Sea, and they are outside their normal area of distribution which is the Indo-Pacific region. When these species succeed in establishing populations in the Mediterranean sea, compete with and begin to replace native species they are “Alien Invasive Species”, as they are an agent of change and a threat to the native biodiversity.Sony VAIO VGN-G11VN/TC Battery

Depending on their impact, Lessepsian migrants are either alien or alien invasive species. In the context of CBD, “introduction" refers to the movement by human agency, indirect or direct, of an alien species outside of its natural range (past or present). The Suez Canal, being an artificial (man made) canal, is a human agency.Sony VAIO VGN-G11XN/B Battery

Lessepsian migrants are therefore “introduced” species (indirect, and unintentional). Whatever wording is chosen, they represent a threat to the native Mediterranean biodiversity, because they are non-indigenous to this sea.Sony VAIO VGN-G1AAPS Battery

In recent years, the Egyptian government's announcement of its intentions to deepen and widen the canal have raised concerns from marine biologists, fearing that such an act will only worsen the invasion of Red Sea species into the Mediterranean, facilitating the crossing of the canal for yet additional species. Sony VAIO VGN-G1AAPSA Battery

Arrival of new tropical Atlantic species

In recent decades, the arrival of exotic species from the tropical Atlantic has become a noticeable feature. Whether this reflects an expansion of the natural area of these species that now enter the Mediterranean through the Gibraltar strait, because of a warming trend of the water caused by Global Warming; Sony VAIO VGN-G1AAPSB Battery

or an extension of the maritime traffic; or is simply the result of a more intense scientific investigation, is still an open question. While not as intense as the “lessepsian” movement, the process deserves to be studied and monitored.

Sea-level rise

Europe may be less threatened by sea-level rise than many developing country regions.Sony VAIO VGN-G1AAPSC Battery

However, coastal ecosystems do appear to be threatened, especially enclosed seas such as the Baltic, the Mediterranean and the Black Sea. These seas have only small and primarily east-west orientated movement corridors, which may restrict northward displacement of organisms in these areas.Sony VAIO VGN-G1ABNS Battery

Sea level rise for the next century (2100) could be between 30 cm (12 in) and 100 cm (39 in) and temperature shifts of a mere 0.05-0.1°C in the deep sea are sufficient to induce significant changes in species richness and functional diversity.

Pollution

Pollution in this region has been extremely high in recent years. Sony VAIO VGN-G1KAP Battery

The United Nations Environment Programme has estimated that 650,000,000 t (720,000,000 short tons) of sewage, 129,000 t (142,000 short tons) of mineral oil, 60,000 t (66,000 short tons) of mercury, 3,800 t (4,200 short tons) of lead and 36,000 t (40,000 short tons) of phosphates are dumped into the Mediterranean each year.Sony VAIO VGN-G1KBN Battery

The Barcelona Convention aims to 'reduce pollution in the Mediterranean Sea and protect and improve the marine environment in the area, thereby contributing to its sustainable development.' Many marine species have been almost wiped out because of the sea's pollution. Sony VAIO VGN-G1KBNA Battery

One of them is the Mediterranean Monk Seal which is considered to be among the world's most endangered marine mammals.

The Mediterranean is also plagued by marine debris. A 1994 study of the seabed using trawl nets around the coasts of Spain, France and Italy reported a particularly high mean concentration of debris;Sony VAIO VGN-G1LAP Battery

an average of 1,935 items per km². Plastic debris accounted for 76%, of which 94% was plastic bags.

Shipping

Some of the world’s busiest shipping routes are in the Mediterranean Sea. It is estimated that approximately 220,000 merchant vessels of more than 100 tonnes cross the Mediterranean Sea each year — about one third of the world’s total merchant shipping.Sony VAIO VGN-G1LBN Battery

These ships often carry hazardous cargo, which if lost would result in severe damage to the marine environment.

The discharge of chemical tank washings and oily wastes also represent a significant source of marine pollution. The Mediterranean Sea constitutes 0.7% of the global water surface and yet receives seventeen percent of global marine oil pollution.Sony VAIO VGN-G218LN/T Battery

It is estimated that every year between 100,000 t (98,000 long tons) and 150,000 t (150,000 long tons) of crude oil are deliberately released into the sea from shipping activities.

Approximately 370,000,000 t (360,000,000 long tons) of oil are transported annually in the Mediterranean Sea (more than 20% of the world total), with around 250-300oil tankers crossing the Sea every day.Sony VAIO VGN-G218N/B Battery

Accidental oil spills happen frequently with an average of 10 spills per year. A major oil spill could occur at any time in any part of the Mediterranean.

Tourism

With a unique combination of pleasant climate, beautiful coastline, rich history and diverse culture the Mediterranean region is the most popular tourist destination in the world — attracting approximately one third of the world’s international tourists.Sony VAIO VGN-G21XP/B Battery

Tourism is one of the most important sources of income for many Mediterranean countries. It also supports small communities in coastal areas and islands by providing alternative sources of income far from urban centres. However, tourism has also played major role in the degradation of the coastal and marine environment.Sony VAIO VGN-G2AANS Battery

Rapid development has been encouraged by Mediterranean governments to support the large numbers of tourists visiting the region each year. But this has caused serious disturbance to marine habitats such as erosion and pollution in many places along the Mediterranean coasts.Sony VAIO VGN-G2AAPS Battery

Tourism often concentrates in areas of high natural wealth, causing a serious threat to the habitats of endangered Mediterranean species such as sea turtles and monk seals. It is ironic that tourism in this region is destroying the foundations of its own existence. And it is inevitable that the tourists will leave the Mediterranean as it becomes more depleted of its natural beauty.Sony VAIO VGN-G2AAPSA Battery

Overfishing

Fish stock levels in the Mediterranean Sea are alarmingly low. The European Environment Agency says that over 65% of all fish stocks in the region are outside safe biological limits and the United Nations Food and Agriculture Organisation,Sony VAIO VGN-G2AAPSB Battery

that some of the most important fisheries — such as albacore and bluefin tuna, hake,marlin, swordfish, red mullet and sea bream — are threatened.

There are clear indications that catch size and quality have declined, often dramatically, and in many areas larger and longer-lived species have disappeared entirely from commercial catches.Sony VAIO VGN-G2AAPSC Battery

Large open water fish like tuna have been a shared fisheries resource for thousands of years but the stocks are now dangerously low. In 1999, Greenpeace published a report revealing that the amount of bluefin tuna in the Mediterranean had decreased by over 80% in the previous 20 years and government scientists warn that without immediate action the stock will collapse.Sony VAIO VGN-G2KAN Battery

Aquaculture

Aquaculture is expanding rapidly — often without proper environmental assessment — and currently accounts for 30% of the fish protein consumed worldwide. The industry claims that farmed seafood lessens the pressure on wild fish stocks, yet many of the farmed species are carnivorous, consuming up to five times their weight in wild fish.Sony VAIO VGN-G2KANA Battery

Mediterranean coastal areas are already over exposed to human influence, with pristine areas becoming ever scarcer. The aquaculture sector adds to this pressure, requiring areas of high water quality to set up farms. The installation of fish farms close to vulnerable and important habitats such as seagrass meadows is particularly concerning.Sony VAIO VGN-G2KBNA Battery

Aquaculture production in the Mediterranean also threatens biodiversity through the introduction of new species to the region, the impact of the farms' organic and chemical effluents on the surrounding environment and coastal habitat destruction.Sony VAIO VGN-NR160E/S Battery

The history of the Mediterranean region is the history of the interaction of the cultures and people of the lands surrounding the Mediterranean Sea —the central superhighway of transport, trade and cultural exchange between diverse peoples. Its history is important to understanding the origin and development of the Israel  and Judah, Mesopotamian, Egyptian, Canaanites, Greek, Roman, Carthaginian, Byzantine, Ottoman, Christian, andIslamic cultures.Sony VAIO VGN-NR160E/T Battery

Dawn of civilization

Its origins can be thought to have been with the Zanclean flood of 5.33 million years ago, described in more detail underMediterranean basin. Two of the first commonly noted human civilizations began near the eastern Mediterranean sea.Sony VAIO VGN-NR160E/W Battery

Common rhetoric suggests that Civilization first developed in Mesopotamia beginning with Sumer in the 4th millennium BC. Soon after, the Nile River valley of ancient Egypt was unified under the Pharaohs in the 4th millennium BC, and civilization quickly spread through theFertile Crescent to the east coast of the sea and throughout the Levant,Sony VAIO VGN-NR180E/S Battery

which happens to make the Mediterranean countries ofEgypt, Syria, Lebanon, Palestine and Israel part of the cradle of civilization. These areas shared similar climates and geographies, but it was more difficult to spread technologies and crops, such as flax, lentil, peas, barley, and cotton to other portions of the Mediterranean basin.Sony VAIO VGN-NR180E/T Battery

In time, large empires developed in Asia Minor, such as the Hittites. The main expansion was delayed until ships sturdy enough to cross the sea were developed. Cyprus and the other islands developed, and the Minoan civilization flourished on the island ofCrete.Sony VAIO VGN-NR290E/S Battery

While the river valley civilizations always had larger populations, the trading societies on the coast of the sea soon became the most prosperous, and rose to power.

Classical antiquity

Two of the most notable Mediterranean civilizations in classical antiquity were the Greek city states and the Phoenicians. Sony VAIO VGN-NR290E/T Battery

The Greeks expanded throughout the Black Sea and south through the Red Sea. The Phoenicians spread through the western Mediterranean reaching North Africa and the Iberian Peninsula. They often provided the naval forces of the Achaemenid Persian Empire and their heartland in the Levant was still dominated by powers rooted east in Mesopotamia or Persia.Sony VAIO VGN-NR298E/S Battery

Hellenistic period

In the northern-most part of ancient Greece, in the ancient kingdom of Macedonia, technological and organizational skills were forged with a long history of cavalry warfare. The hetairoi (Companion cavalry) was considered the strongest of their time.Sony VAIO VGN-NR460E/L Battery

Under Alexander the Great, this force turned east, and in a series of three decisive battles, routed the Persian forces and took their empire, which included Egypt and the Phoenician lands. The major centres of the Mediterranean at the time became part of Alexander's empire as a result. Sony VAIO VGN-NR460E/P Battery

His empire quickly disintegrated, and the Middle East, Egypt, and Greece were soon again independent. Alexander's conquests spread Greek knowledge and ideas throughout the region.

Roman-Carthaginian rivalry

These eastern powers soon began to be overshadowed by those further west. Sony VAIO VGN-NR498E/L Battery

In North Africa the former Phoenician colony of Carthagerose to dominate its surroundings with an empire that contained many of the former Phoenician holdings. However, it was a city on the Italian Peninsula, Rome, that would eventually dominate the entire Mediterranean basin. Sony VAIO VGN-NR498E/S Battery

Spreading first through Italy, Rome defeated Carthage in the Punic Wars, despite Hannibal's famous efforts against Rome in the Second Punic War. After the Third Punic War, Rome then became the leading force in the Mediterranean region. The Romans soon spread east taking Greece, and the Greek heritage played an important role in the Roman Empire.Sony VAIO VGN-NR498E/T Battery

By this point the coastal trading cultures were thoroughly dominant over the inland river valleys that had once been the heart of the great powers. Egyptian power moved from the Nile cities to the coastal ones, especially Alexandria. Mesopotamia became a fringe border region between the Roman Empire and the Persians.Sony VAIO VGN-NR498E/W Battery

Roman Lake

When Augustus founded the Roman Empire, the Mediterranean sea began to be called Mare Nostrum (Latin: "Our Sea") by the Romans. Their empire was centered on this sea and all the area was full of commerce and naval development. Sony VAIO VGN-NR50 Battery

For the first time in history an entire sea (the Mediterranean) was free of piracy. For several centuries the Mediterranean was a "Roman Lake", surrounded on all sides by the empire.

The empire began to crumble, however, in the fifth century and Rome collapsed after 476 AD.Sony VAIO VGN-NR50B Battery

Temporarily the east was again dominant as the Byzantine Empire formed from the eastern half of the Roman one. The western part of the empire, Gaul, Iberia, and the Maghreb were invaded by nomadic horse peoples from the Eurasian steppe. These conquerors soon became settled, and adopted many of the local customs, forming many small and warring kingdoms.Sony VAIO VGN-NR51 Battery

Islamic Golden Age

Another power was rising in the east, that of Islam, whilst the Byzantine Roman and Sassanid Persian empires were both weakened by centuries of stalemate warfare during the Roman-Persian Wars. Sony VAIO VGN-NR51B Battery

In a series of rapid Muslim conquests, the Arab armies, motivated by Islam and led by the Caliphs and skilled military commanders such as Khalid ibn al-Walid, swept through most of the Middle East;reducing Byzantine lands by more than half and completely engulfing the Persian lands.Sony VAIO VGN-NR52 Battery

2-battery-28016.htm" title="Sony VAIO VGN-NR52 laptop battery">In Anatolia, their expansion was blocked by the still capable Byzantines with the help of the Bulgarians. The Byzantine provinces of Roman Syria, North Africa, and Sicily, however, could not mount such a resistance, and the Muslim conquerors swept through those regions. Sony VAIO VGN-NR52B Battery

At the far west, they crossed the sea taking Visigothic Hispania before being halted in southern France by the Franks. At its greatest extent, the Arab Empirecontrolled 3/4 of the Mediterranean region, the only other empire besides the Roman Empire to control most of the Mediterranean Sea.Sony VAIO VGN-NR71B Battery

Much of North Africa became a peripheral area to the main Muslim centres in the Middle East, but Iberia (Al Andalus) and Morocco soon broke from this distant control and founded one of the world's most advanced societies at the time, along with Baghdad near the eastern Mediterranean.Sony VAIO VGN-NR71B2 Battery

Between 831 and 1071, the Emirate of Sicily was one of the major centres of Islamic culture in the Mediterranean. After its conquest by the Normans the island developed its own distinct culture with the fusion of Arab, Western and Byzantine influences. Palermo remained a leading artistic and commercial centre of the Mediterranean well into the Middle Ages.Sony VAIO VGN-NR72B Battery

Europe was reviving, however, as more organized and centralized states began to form in the later Middle Ages after the Renaissance of the 12th century. Motivated by religion and dreams of conquest, the kings of Europe launched a number of Crusades to try to roll back Muslim power and retake the holy land. Sony VAIO VGN-NS10E/S Battery

The Crusades were unsuccessful in this goal, but they were far more effective in weakening the already tottering Byzantine Empire that began to lose increasing amounts of territory to the Seljuk Turks and later to the Ottoman Turks. They also rearranged the balance of power in the Muslim world as Egypt once again emerged as a major power in the eastern Mediterranean.Sony VAIO VGN-NS10J/S Battery

Late Middle Ages

Europe continued to increase in power as the Renaissance began in Italy. The Italian "Repubbliche Marinare" (Maritime Republics) of Venice, Genoa, Amalfi and Pisa developed their own "empires" in the Mediterranean shores. Sony VAIO VGN-NS10L/S Battery

The Islamic states had never been major naval powers, and trade from the east to Europe was soon in the hands of Italian traders, especially the Venetians, who profited immensely from it. Republic of Ragusa used diplomacy to further trade and maintained a libertarian approach in civil matters to further sentiment in its inhabitants. Sony VAIO VGN-NS110E/L Battery

The Western Mediterranean sea was dominated by the Crown of Aragon: thanks to their possessions of Sicily, the Kingdom of Naples, Sardinia, the Balearic Islands, the Duchy of Athens the Duchy of Neopatria, and several northern African cities, by the 1420s they kept tight control over the trade routes of that linked the Western and Eastern Mediterranean. Sony VAIO VGN-NS110E/S Battery

Their army was the biggest in the Mediterranean sea, and during the 15th century its power remained unchallenged.

Ottoman power continued to grow, and in 1453, the Byzantine Empire was extinguished with the fall of Constantinople. Sony VAIO VGN-NS110E/W Battery

The Ottomans already controlled Greece, Bulgaria and much of the Balkans (except Albania, due to its resistance), and soon also began to spread through North Africa. North Africa had grown wealthy from the trade across the Sahara Desert, but the Portuguese, who, along with other Christian powers, Sony VAIO VGN-NS115N/S Battery

had been engaged in a long campaign to evict the Muslims from Iberia, had found a method to circumvent this trade by trading directly with West Africa. This was enabled by a new type of ships, the caravel, that made trade in the rough Atlantic waters profitable for the first time. Sony VAIO VGN-NS11ER/S Battery

The reduction in the Saharan trade weakened North Africa, and made them an easy target for the Ottomans.

Modern era

The growing naval prowess of the European powers confronted further rapid Ottoman expansion in the region when the Battle of Lepanto checked the power of the Ottoman navy. Sony VAIO VGN-NS11E/S Battery

However, as Braudel argued forcefully, this only slowed the Ottoman expansion instead of ending it. The prized island of Cyprus became Ottoman in 1571. The last resistance in Tunisia ended in 1574 and almost a generation long siege in Crete pushed Venetians out of this strategic island in 1669. Sony VAIO VGN-NS11J/S Battery

A balance of power was then established between Spain and Ottoman Empire until 18th century, each dominating their respective half of Mediterranean, reducing Italian navies as naval powers increasingly more irrelevant. Furthermore, the Ottoman Empire had succeeded in their objective of extending Muslim rule across the North African coast.Sony VAIO VGN-NS11L/S Battery

The development of oceanic shipping began to affect the entire Mediterranean, however. While once all trade from the east had passed through the region, the circumnavigation of Africa allowed gold, spices, and dyes to be imported directly to the Atlantic ports of western Europe. Sony VAIO VGN-NS11MR/S Battery

The Americas were also a source of extreme wealth to the western powers, from which some of the Mediterranean states were largely cut off. The base of European power thus shifted northward and the once wealthy Italy became a peripheral area dominated by foreigners. Sony VAIO VGN-NS11M/S Battery

The Ottoman Empire also began a slow decline that saw its North African possessions gain de facto independence and its European holdings gradually reduced by the increasing power of Austria and Russia.

By the nineteenth century the European States were vastly more powerful, and began to colonize North Africa. Sony VAIO VGN-NS11SR/S Battery

France spread its power south by taking Algeria in 1830 and later Tunisia. Britain gained control of Egypt in 1882. Italy conquered Libya from the Ottomans in 1911. The Ottoman Empire finally collapsed in the First World War, and its holdings were carved up among France and Britain,Sony VAIO VGN-NS11S/S Battery

but the Turkish regions quickly regained their independence, becoming the independent state of Turkey in 1923. During the first half of the twentieth century the Mediterranean was at the center of the expansion of the Kingdom of Italy, and was one of the main areas of battle during World War II between the Axis and the Allies. Sony VAIO VGN-NS11ZR/S Battery

Post-world war period was marked by increasing activity in the Eastern Mediterranean, where naval actions formed part of ongoing Arab-Israeli conflict and Turkey had occupied the northern part of Cyprus. American naval power made the Mediterranean its permanent base during the Cold war. Sony VAIO VGN-NS11Z/S Battery

Today, the Mediterranean Sea is the southern border of the European Union.

In biogeography, the Mediterranean Basin refers to the lands around the Mediterranean Sea that have a Mediterranean climate, with mild, rainy winters and hot, dry summers, which supports characteristic Mediterranean forests, woodlands, and scrub vegetation. Sony VAIO VGN-NS12M/S Battery

As a rule of thumb, the Mediterranean Basin is the Old World region where olive trees grow.

Geography

The Mediterranean basin covers portions of three continents, Europe, Asia, and Africa.Sony VAIO VGN-NS12M/W Battery

Europe lies to the north, and three large Southern European peninsulas, the Iberian Peninsula, Italian Peninsula, and the Balkan Peninsula, extend into the Mediterranean-climate zone. A system of folded mountains, including the Pyreneesdividing Spain from France, the Alps dividing Italy from Central Europe, Sony VAIO VGN-NS12S/S Battery

the Dinaric Alps along the eastern Adriatic, and the Balkan and Rhodope mountains of the Balkan Peninsula divide the Mediterranean from the temperate climate regions of Western and Central Europe.

The Mediterranean Basin extends into Western Asia, covering the western and southern portions of the peninsula ofTurkey, excluding the temperate-climate mountains of central Turkey.Sony VAIO VGN-NS21M/P Battery

It includes the Mediterranean climate Levant at the eastern end of the Mediterranean, bounded on the east and south by the Syrian and Negev deserts.

The northern portion of the Maghreb region of northwestern Africa has a Mediterranean climate, separated from theSahara Desert, which extends across North Africa, by the Atlas Mountains. Sony VAIO VGN-NS21M/W Battery

In the eastern Mediterranean the Sahara extends to the southern shore of the Mediterranean, with the exception of the northern fringe of the peninsula of Cyrenaica in Libya, which has a dry Mediterranean climate.

Geology and paleoclimatology

The Mediterranean Basin was shaped by the ancient collision of the northward-moving African-Arabian continent with the stable Eurasian continent. Sony VAIO VGN-NS21S/S Battery

As Africa-Arabia moved north, it closed the former Tethys Sea, which formerly separated Eurasia from the ancient supercontinent of Gondwana, of which Africa was part. At the same time about 170 mya in the Jurassic, a small Neotethys ocean basin formed shortly before the Tethys Sea was closed at the eastern end.Sony VAIO VGN-NS21S/W Battery

The collision pushed up a vast system of mountains, extending from the Pyrenees in Spain to the Zagros Mountains in Iran. This episode of mountain building, known as the Alpine orogeny, occurred mostly during the Oligocene (34 to 23 million years ago (mya)) and Miocene (23 to 5.3 mya) epochs. Sony VAIO VGN-NS21Z/S Battery

The Neotethys became larger during these collisions and associated folding and subduction. About 6 mya during the late Miocene, the Mediterranean was closed at its western end by drifting Arabia, which caused the entire sea to evaporate. The episodes of sea drawdown and reflooding are best known in the Messinian Salinity Crisis, when the Atlantic reflooded the basin at least 69 times.Sony VAIO VGN-NS31M/P Battery

The end of the Miocene also marked a change in the Mediterranean Basin's climate. Fossil evidence shows that the Mediterranean Basin had a relatively humid subtropical climate with summer rainfall during the Miocene, which supported laurel forests. Sony VAIO VGN-NS31M/W Battery

The shift to a Mediterranean climate occurred within the last 3.2 - 2.8 million years, during the Pliocene epoch, as summer rainfall decreased. The subtropical laurel forests retreated, although they persisted on the islands ofMacaronesia off the Atlantic coast of Iberia and North Africa, and the present Mediterranean vegetation evolved, Sony VAIO VGN-NS31S/S Battery

dominated by coniferous trees and sclerophylloustrees and shrubs, with small, hard, waxy leaves that prevent moisture loss in the dry summers. Much of these forests and shrublands have been altered beyond recognition by thousands of years of human habitation. There are now very few relatively intact natural areas in what was once a heavily wooded region.Sony VAIO VGN-NS31Z/P Battery

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