mar Mediterráneo | |
---|---|
Localización | Europa occidental , sur de Europa , norte de África y Asia occidental |
Coordenadas | 35 ° N 18 ° E / 35 ° N 18 ° E Coordenadas: 35 ° N 18 ° E / 35 ° N 18 ° E |
Escribe | Mar |
Entradas primarias | Océano Atlántico , Mar de Mármara , Nilo , Ebro , Ródano , Chelif , Po |
Países de la cuenca | alrededor de 60
|
Área de superficie | 2,500,000 km 2 (970,000 millas cuadradas) |
Profundidad promedio | 1.500 m (4.900 pies) |
Max. profundidad | 5.267 m (17.280 pies) |
Volumen de agua | 3,750,000 km 3 (900,000 millas cúbicas) |
Tiempo de residencia | 80-100 años [1] |
Islas | 3300+ |
Asentamientos | Alejandría , Barcelona , Argel , Izmir , Roma , Atenas , Beirut , Trípoli , Túnez , Tánger , Tel Aviv-Yafo , Split , ( lista completa ) |
El mar Mediterráneo es un mar conectado con el océano Atlántico , rodeado por la cuenca mediterránea y casi completamente cerrado por tierra: al norte con Europa occidental y meridional y Anatolia , al sur con el norte de África y al este con el Levante . El mar ha jugado un papel central en la historia de la civilización occidental. Aunque el Mediterráneo a veces se considera parte del Océano Atlántico, generalmente se lo conoce como una masa de agua separada. La evidencia geológica indica que hace alrededor de 5,9 millones de años, el Mediterráneo estaba aislado del Atlántico y se desecó parcial o completamente durante un período de unos 600.000 años durante la crisis de salinidad mesiniana antes de ser rellenado por la inundación de Zanclean hace unos 5,3 millones de años.
El mar Mediterráneo cubre un área de aproximadamente 2.500.000 km 2 (970.000 millas cuadradas), [2] que representa el 0,7% de la superficie oceánica global , pero su conexión con el Atlántico a través del Estrecho de Gibraltar , el estrecho que conecta el Océano Atlántico con el mar Mediterráneo y separa España en Europa de Marruecos en África, tiene sólo 14 km (9 millas) de ancho. En oceanografía , a veces se le llama Mar Mediterráneo Eurafricano , Mar Mediterráneo Europeo o Mar Mediterráneo Africano para distinguirlo demares mediterráneos en otros lugares. [3] [4]
El mar Mediterráneo tiene una profundidad promedio de 1.500 m (4.900 pies) y el punto más profundo registrado es 5.267 m (17.280 pies) en el Calypso Deep en el Mar Jónico . Se encuentra entre las latitudes 30 ° y 46 ° N y longitudes 6 ° W y 36 ° E . Su longitud oeste-este, desde el Estrecho de Gibraltar hasta el Golfo de Iskenderun , en la costa sureste de Turquía, es de unos 4.000 kilómetros (2.500 millas).
El mar fue una ruta importante para los comerciantes y viajeros de la antigüedad, facilitando el intercambio comercial y cultural entre los pueblos de la región. La historia de la región mediterránea es fundamental para comprender los orígenes y el desarrollo de muchas sociedades modernas. El Imperio Romano mantuvo la hegemonía náutica sobre el mar durante siglos.
Los países que rodean el Mediterráneo en el sentido de las agujas del reloj son España , Francia , Mónaco , Italia , Eslovenia , Croacia , Bosnia y Herzegovina , Montenegro , Albania , Grecia , Turquía , Siria , Líbano , Israel , Egipto , Libia , Túnez , Argelia y Marruecos ; Malta y Chipreson países insulares en el mar. Además, la Franja de Gaza y los Territorios Británicos de Ultramar de Gibraltar y Akrotiri y Dhekelia tienen costas en el mar.
Los antiguos egipcios llamaron al Mediterráneo Wadj-wr / Wadj-Wer / Wadj-Ur. Este término (literalmente “gran verde”) fue el nombre que los antiguos egipcios dieron a la región semisólida y semiacuática caracterizada por bosques de papiros al norte del delta del Nilo cultivado y, por extensión, al mar más allá. [5]
Los antiguos griegos llamaban al Mediterráneo simplemente ἡ θάλασσα ( hē thálassa ; "el Mar") oa veces ἡ μεγάλη θάλασσα ( hē megálē thálassa ; "el Gran Mar"), ἡ ἡμετέρα θάλασσα ( hē hēmetérā thálassa ); ἡ θάλασσα ἡ καθ'ἡμᾶς ( hē thálassa hē kath'hēmâs ; "el mar que nos rodea").
Los romanos lo llamaron Mare Magnum ("Gran Mar") o Mare Internum ("Mar Interior") y, comenzando con el Imperio Romano , Mare Nostrum ("Nuestro Mar"). El término Mare Mediterrāneum aparece más tarde: Solinus aparentemente lo usó en el siglo III, pero el testimonio más antiguo que existe de él se encuentra en el siglo VI, en Isidoro de Sevilla . [6] [7] Significa 'en medio de la tierra, tierra adentro' en latín , un compuesto de medius ("medio"), terra ("tierra, tierra") y -āneus ("que tiene la naturaleza de") .
La palabra latina es un calco del griego μεσόγειος ( mesógeios ; "tierra adentro"), de μέσος ( mésos , "en el medio") y γήινος ( gḗinos , "de la tierra"), de γῆ ( gê , "tierra, tierra" ). El significado original puede haber sido "el mar en medio de la tierra", en lugar de "el mar encerrado por la tierra". [8] [9]
Los antiguos iraníes lo llamaron el "Mar Romano", en los textos persas clásicos se llamaba Daryāy-e Rōm (دریای روم) que puede ser de la forma persa media , Zrēh ī Hrōm (𐭦𐭫𐭩𐭤 𐭩 𐭤𐭫𐭥𐭬). [10]
Los cartagineses lo llamaron el "Mar de Siria". En los textos sirios antiguos, las epopeyas fenicias y en la Biblia hebrea , se lo conocía principalmente como el "Gran Mar", HaYam HaGadol , ( Números ; Libro de Josué ; Ezequiel ) o simplemente como "El Mar" ( 1 Reyes ). Sin embargo, también se le ha llamado el "Mar Hinder" debido a su ubicación en la costa oeste de la Gran Siria o Tierra Santa (y por lo tanto detrás de una persona que mira hacia el este), que a veces se traduce como "Mar Occidental". Otro nombre fue el "Mar de los filisteos ",(Libro del Éxodo ), del pueblo que habita una gran parte de sus costas cerca de los israelitas . En hebreo moderno , se llama HaYam HaTikhon 'el Mar Medio'. [11] En los textos persas clásicos se llamaba Daryāy-e Šām (دریای شام) "El Mar Occidental" o "Mar de Siria". [12]
En árabe moderno , se lo conoce como al-Baḥr [al-Abyaḍ] al-Mutawassiṭ ( البحر [الأبيض] المتوسط ) 'el Mar Medio [Blanco]'. En la literatura árabe islámica y más antigua, era Baḥr al-Rūm (ī) ( بحر الروم o بحر الرومي }) 'el Mar de los Romanos' o 'el Mar Romano'. Al principio, ese nombre se refería solo al Mediterráneo oriental, pero luego se extendió a todo el Mediterráneo. Otros nombres árabes eran Baḥr al-šām (ī) ( بحر الشام ) ("el Mar de Siria") y Baḥr al-Maghrib ( بحرالمغرب ) ("el Mar del Oeste"). [13] [7]
En turco , es el Akdeniz 'el Mar Blanco'; en otomano, ﺁق دكيز , que a veces significa solo el mar Egeo . [14] El origen del nombre no está claro, ya que no se conoce en fuentes griegas, bizantinas o islámicas anteriores. Puede ser para contrastar con el Mar Negro . [13] [11] [15] En persa, el nombre se tradujo como Baḥr-i Safīd , que también se utilizó en el turco otomano posterior . Probablemente sea el origen de la frase griega coloquial Άσπρη Θάλασσα ( Άspri Thálassa , literalmente "Mar Blanco"). [13]
Según Johann Knobloch, en la antigüedad clásica , las culturas del Levante usaban colores para referirse a los puntos cardinales: el negro se refería al norte (explicando el nombre del Mar Negro ), el amarillo o azul al este, el rojo al sur (por ejemplo, el Mar Rojo). ) y blanco al oeste. Esto explicaría el griego Άspri Thálassa , el búlgaro Byalo More , el turco Akdeniz y la nomenclatura árabe descrita anteriormente, lit. "Mar Blanco". [dieciséis]
Algunas de las civilizaciones antiguas más importantes del mundo que fueron la base de toda la cultura occidental se ubicaron alrededor de las costas del Mediterráneo y fueron muy influenciadas por su proximidad al mar. Proporcionó rutas para el comercio, la colonización y la guerra, así como alimentos (provenientes de la pesca y la recolección de otros mariscos) para numerosas comunidades a lo largo de los siglos. [17]
Debido al clima, la geología y el acceso al mar compartidos, las culturas centradas en el Mediterráneo tendían a tener cierta extensión de cultura e historia entrelazadas.
Dos de las civilizaciones mediterráneas más notables de la antigüedad clásica fueron las ciudades estado griegas y los fenicios , que colonizaron extensamente las costas del Mediterráneo. Más tarde, cuando Augusto fundó el Imperio Romano , los romanos se refirieron al Mediterráneo como Mare Nostrum ("Nuestro Mar"). Durante los siguientes 400 años, el Imperio Romano controló por completo el mar Mediterráneo y prácticamente todas sus regiones costeras desde Gibraltar hasta el Levante.
Darío I de Persia , que conquistó el Antiguo Egipto, construyó un canal que unía el Mediterráneo con el Mar Rojo . El canal de Darío era lo suficientemente ancho como para que dos trirremes se cruzaran con los remos extendidos, y requirió cuatro días para atravesarlo. [18]
En 2019, el equipo arqueológico de expertos del Centro de Investigación Subacuática de la Universidad de Akdeniz (UA) reveló un naufragio que data de hace 3.600 años en el mar Mediterráneo en Turquía . Se utilizaron 1,5 toneladas de lingotes de cobre encontrados en el barco para estimar su edad. El gobernador de Antalya Munir Karaloğlu describió este valioso descubrimiento como el " Göbeklitepe del mundo submarino". Se ha confirmado que el naufragio, que data del 1600 a. C., es más antiguo que el " naufragio de Uluburun " que data del 1400 a. C. [19 ] [20] [21] [22]
El Imperio Romano Occidental colapsó alrededor del 476 d.C. Temporalmente, el este volvió a dominar a medida que el poder romano vivía en el Imperio Bizantino formado en el siglo IV a partir de la mitad oriental del Imperio Romano . Otro poder surgió en el siglo VII, y con él la religión del Islam , que pronto se extendió desde el este; en su mayor extensión, el Imperio Árabe [ ¿cuál? ] controló el 75% [ dudoso
] de la región mediterránea y dejó una huella duradera en sus costas este y sur.Las invasiones árabes interrumpieron las relaciones comerciales entre Europa occidental y oriental al tiempo que interrumpieron las rutas comerciales con los imperios de Asia oriental. Sin embargo, esto tuvo el efecto indirecto de promover el comercio a través del Mar Caspio . La exportación de cereales de Egipto se reorientó hacia el mundo oriental . Los marineros y comerciantes judíos transportaban productos de los imperios de Asia oriental, como la seda y las especias, desde Egipto a puertos como Venecia y Constantinopla . Las incursiones vikingas interrumpieron aún más el comercio en Europa occidental y lo paralizaron. Sin embargo, los escandinavos desarrollaron el comercio desde Noruega hasta el Mar Blanco., mientras que también comercializa artículos de lujo de España y el Mediterráneo. Los bizantinos a mediados del siglo VIII retomaron el control del área alrededor de la parte noreste del Mediterráneo. Los barcos venecianos del siglo IX se armaron para contrarrestar el acoso de los árabes mientras concentraban el comercio de productos asiáticos en Venecia. [23]
Los fatimíes mantuvieron relaciones comerciales con las ciudades-estado italianas como Amalfi y Génova antes de las Cruzadas, según los documentos de El Cairo Geniza . Un documento fechado en 996 menciona a los comerciantes amalfianos que viven en El Cairo . Otra carta dice que los genoveses habían comerciado con Alejandría . El califa al-Mustansir había permitido que los comerciantes amalfianos residieran en Jerusalén alrededor de 1060 en lugar del hospicio latino . [24]
Las Cruzadas llevaron al florecimiento del comercio entre Europa y la región más ultraperiférica . [25] Génova, Venecia y Pisa crearon colonias en regiones controladas por los cruzados y llegaron a controlar el comercio con Oriente. Estas colonias también les permitieron comerciar con el mundo oriental. Aunque la caída de los estados cruzados y los intentos de los Papas de prohibir las relaciones comerciales con los estados musulmanes interrumpieron temporalmente el comercio con Oriente, continuó sin embargo. [26]
Europa comenzó a revivir, sin embargo, a medida que los estados más organizados y centralizados comenzaron a formarse en la última Edad Media después del Renacimiento del siglo XII .
El poder otomano con base en Anatolia siguió creciendo y en 1453 extinguió el Imperio bizantino con la conquista de Constantinopla . Los otomanos tomaron el control de gran parte del mar en el siglo XVI y mantuvieron bases navales en el sur de Francia (1543-1544), Argelia y Túnez. Barbarroja , el famoso capitán otomano es un símbolo de esta dominación con la victoria de la Batalla de Preveza (1538). La batalla de Djerba (1560) marcó la cúspide de la dominación naval otomana en el Mediterráneo. A medida que aumentaba la destreza naval de las potencias europeas, se enfrentaron a la expansión otomana en la región cuando la Batalla de Lepanto (1571) frenó el poder de la Armada Otomana.. Esta fue la última batalla naval que se libró principalmente entre galeras .
Los piratas de Berbería del noroeste de África se aprovecharon de la navegación y las costas cristianas en el mar Mediterráneo occidental. [27] Según Robert Davis, entre los siglos XVI y XIX, los piratas capturaron entre 1 millón y 1,25 millones de europeos como esclavos. [28]
El desarrollo del transporte marítimo comenzó a afectar a todo el Mediterráneo. Una vez, la mayor parte del comercio entre Europa Occidental y Oriente había pasado por la región, pero después de la década de 1490, el desarrollo de una ruta marítima hacia el Océano Índico permitió la importación de especias asiáticas y otros productos a través de los puertos atlánticos de Europa occidental. [29] [30] [31]
El mar siguió siendo estratégicamente importante. El dominio británico de Gibraltar aseguró su influencia en África y el suroeste de Asia. Especialmente después de las batallas navales de Abukir (1799, Batalla del Nilo ) y Trafalgar (1805), los británicos habían fortalecido durante mucho tiempo su dominio en el Mediterráneo. [32] Las guerras incluyeron la guerra naval en el Mediterráneo durante la Primera Guerra Mundial y el teatro mediterráneo de la Segunda Guerra Mundial .
Con la apertura del Canal de Suez sin esclusas en 1869, el flujo comercial entre Europa y Asia cambió fundamentalmente. La ruta más rápida ahora atravesaba el Mediterráneo hacia África Oriental y Asia. Esto llevó a una preferencia por los países mediterráneos y sus puertos como Trieste con conexiones directas a Europa Central y Oriental experimentaron un rápido ascenso económico. En el siglo XX, la I y II Guerra Mundial, así como la Crisis de Suez y la Guerra Fría provocaron un cambio de rutas comerciales hacia los puertos del norte de Europa, que volvieron a cambiar hacia los puertos del sur a través de la integración europea, la activación del Silk Carretera y libre comercio mundial. [33]
En 2013, el presidente maltés describió el mar Mediterráneo como un "cementerio" debido a la gran cantidad de migrantes que se ahogaron allí después de que sus barcos volcaran. [34] El presidente del Parlamento Europeo, Martin Schulz, dijo en 2014 que la política migratoria europea "convirtió el Mediterráneo en un cementerio", refiriéndose al número de refugiados ahogados en la región como resultado directo de las políticas. [35] Un funcionario azerbaiyano describió el mar como "un cementerio ... donde la gente muere". [36]
Tras el naufragio de migrantes de Lampedusa en 2013 , el gobierno italiano decidió fortalecer el sistema nacional de patrullaje del mar Mediterráneo autorizando la " Operación Mare Nostrum ", una misión militar y humanitaria para rescatar a los migrantes y detener a los traficantes de inmigrantes. En 2015, más de un millón de migrantes cruzaron el mar Mediterráneo hacia Europa. [37]
Italia se vio particularmente afectada por la crisis migratoria europea . Desde 2013, más de 700.000 migrantes han aterrizado en Italia [38], principalmente africanos subsaharianos. [39]
El mar Mediterráneo conecta:
El Canal de Suez artificial de 163 km (101 millas) de largo en el sureste conecta el Mar Mediterráneo con el Mar Rojo sin esclusa para barcos, porque el nivel del agua es esencialmente el mismo. [11] [40]
El punto más occidental del Mediterráneo se encuentra en la transición del Mar de Alborán al Estrecho de Gibraltar, el punto más oriental se encuentra en la costa del Golfo de Iskenderun en el sureste de Turquía. El punto más al norte del Mediterráneo se encuentra en la costa del Golfo de Trieste cerca de Monfalcone en el norte de Italia, mientras que el punto más al sur está en la costa del Golfo de Sidra cerca de la ciudad libia de El Agheila .
Las grandes islas del Mediterráneo incluyen:
El arco alpino , que también tiene un gran impacto meteorológico en el área mediterránea, toca el Mediterráneo por el oeste en los alrededores de Niza .
El clima mediterráneo típico tiene veranos calurosos y secos e inviernos suaves y lluviosos. Los cultivos de la región incluyen aceitunas , uvas , naranjas , mandarinas , algarrobos y corcho .
El mar Mediterráneo incluye 12 mares marginales : [41] [42] [43]
Número | Mar | Área (km 2 ) | Países y territorios marginales |
---|---|---|---|
1 | Mar de Libia | 350.000 | Libia , Grecia , Malta , Italia |
2 | Mar levantino | 320 000 | Turquía , Siria , Líbano , Israel , Palestina , Egipto , Grecia , Chipre , Akrotiri y Dhekelia |
3 | Mar Tirreno | 275.000 | Italia , Francia |
4 | Mar Egeo | 214.000 | Turquía , Grecia |
5 | mar Jónico | 169.000 | Grecia , Albania , Italia |
6 | Mar balear | 150.000 | Francia , España |
7 | mar Adriatico | 138.000 | Albania , Bosnia y Herzegovina , Croacia , Italia , Montenegro , Eslovenia |
8 | Mar de Cerdeña | 120.000 | Italia , España |
9 | Mar de Creta | 95.000 | Grecia , Libia , Egipto |
10 | Mar de Liguria | 80.000 | Italia , Francia |
11 | Mar de Alborán | 53.000 | España , Marruecos , Argelia , Gibraltar |
12 | Mar de Mármara | 11,500 | pavo |
- | Otro | ~ 500 000 | Consiste en golfos, estrechos, canales y otras partes que no tienen el nombre de un mar específico. |
Total | mar Mediterráneo | ~ 2.500.000 |
Nota 1: La Organización Hidrográfica Internacional define el área como Mar Mediterráneo genérico, en la Cuenca Occidental. No reconoce la etiqueta Mar de Cerdeña . [44]
Nota 2: el mar de Tracia y el mar de Myrtoan son mares que forman parte del mar Egeo .
Nota 3: El Mar Negro no se considera parte de él.
La Organización Hidrográfica Internacional define los límites del Mar Mediterráneo de la siguiente manera: [44] Extendiéndose desde el Estrecho de Gibraltar en el oeste hasta las entradas a los Dardanelos y el Canal de Suez en el este, el Mar Mediterráneo limita con las costas de Europa. , África y Asia y se divide en dos cuencas profundas:
The following countries have a coastline on the Mediterranean Sea:
Several other territories also border the Mediterranean Sea (from west to east):
Exclusive economic zones in Mediterranean Sea:[42][47]
Number | Country | Area (Km2) |
---|---|---|
1 | Italy | 541,915 |
2 | Greece | 493,708 |
3 | Libya | 355,604 |
4 | Spain | 260,000 |
5 | Egypt | 169,125 |
6 | Algeria | 128,843 |
7 | Tunisia | 102,047 |
8 | Cyprus | 98,088 |
9 | France | 88,389 |
10 | Turkey | 72,195 |
11 | Croatia | 59,032 |
12 | Malta | 55,542 |
13 | Israel | 25,139 |
14 | Lebanon | 19,265 |
15 | Morocco | 18,302 |
16 | Albania | 13,691 |
17 | Syria | 10,189 |
18 | Montenegro | 7,745 |
19 | Palestine | 2,591 |
20 | Monaco | 288 |
21 | Slovenia | 220 |
22 | Bosnia and Herzegovina | 50 |
23 | United Kingdom | Very low |
Total | Mediterranean Sea | 2,500,000 |
The Coastline length is about 46,000 km.[48][49][50]
Major cities (municipalities), with populations larger than 200,000 people, bordering the Mediterranean Sea include:
Country | Cities |
---|---|
Algeria | Algiers, Annaba, Oran |
Egypt | Alexandria, Damietta, Port Said |
France | Marseille, Toulon, Nice |
Greece | Athens, Thessaloniki, Patras, Heraklion |
Israel | Ashdod, Haifa, Netanya, Tel Aviv |
Italy | Bari, Catania, Genoa, Messina, Naples, Palermo, Rome, Taranto, Trieste, Venice |
Lebanon | Beirut, Tripoli |
Libya | Benghazi, Misrata, Tripoli, Zawiya, Zliten |
Malta | Valletta |
Morocco | Tétouan, Tangier |
Palestine | Gaza City |
Spain | Alicante, Almería, Badalona, Barcelona, Cartagena, Málaga, Palma de Mallorca, Valencia. |
Syria | Latakia, Tartus |
Tunisia | Sfax, Sousse, Tunis |
Turkey | Alanya, Antalya, Ayvalık, Bodrum, Çanakkale, Çeşme, Fethiye, Foça, İskenderun, Kemer, Kuşadası, Marmaris, Mersin. |
The International Hydrographic Organization (IHO) divides the Mediterranean into a number of smaller waterbodies, each with their own designation (from west to east):[44]
Some other seas whose names have been in common use from the ancient times, or in the present:
Many of these smaller seas feature in local myth and folklore and derive their names from such associations.
In addition to the seas, a number of gulfs and straits are recognised:
Country | Island | Area in km2 | Population |
---|---|---|---|
Italy | Sicily | 25,460 | 5,048,995 |
Italy | Sardinia | 23,821 | 1,672,804 |
Cyprus | Cyprus | 9,251 | 1,088,503 |
France | Corsica | 8,680 | 299,209 |
Greece | Crete | 8,336 | 623,666 |
Greece | Euboea | 3,655 | 218.000 |
Spain | Majorca | 3,640 | 869,067 |
Greece | Lesbos | 1,632 | 90,643 |
Greece | Rhodes | 1,400 | 117,007 |
Greece | Chios | 842 | 51,936 |
Much of the Mediterranean coast enjoys a hot-summer Mediterranean climate. However, most of its southeastern coast has a hot desert climate, and much of Spain's eastern (Mediterranean) coast has a cold semi-arid climate. Although they are rare, tropical cyclones occasionally form in the Mediterranean Sea, typically in September–November.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Málaga[51] | 16 | 15 | 15 | 16 | 17 | 20 | 22 | 23 | 22 | 20 | 18 | 16 | 18.3 |
Barcelona[52] | 13 | 12 | 13 | 14 | 17 | 20 | 23 | 25 | 23 | 20 | 17 | 15 | 17.8 |
Marseille[53] | 13 | 13 | 13 | 14 | 16 | 18 | 21 | 22 | 21 | 18 | 16 | 14 | 16.6 |
Naples[54] | 15 | 14 | 14 | 15 | 18 | 22 | 25 | 27 | 25 | 22 | 19 | 16 | 19.3 |
Malta[55] | 16 | 16 | 15 | 16 | 18 | 21 | 24 | 26 | 25 | 23 | 21 | 18 | 19.9 |
Venice[56] | 11 | 10 | 11 | 13 | 18 | 22 | 25 | 26 | 23 | 20 | 16 | 14 | 17.4 |
Athens[57] | 16 | 15 | 15 | 16 | 18 | 21 | 24 | 24 | 24 | 21 | 19 | 18 | 19.3 |
Heraklion[58] | 16 | 15 | 15 | 16 | 19 | 22 | 24 | 25 | 24 | 22 | 20 | 18 | 19.7 |
Antalya[59] | 17 | 17 | 16 | 17 | 21 | 24 | 27 | 29 | 27 | 25 | 22 | 19 | 21.8 |
Limassol[60] | 18 | 17 | 17 | 18 | 20 | 24 | 26 | 27 | 27 | 25 | 22 | 19 | 21.7 |
Mersin[61] | 18 | 17 | 17 | 18 | 21 | 25 | 28 | 29 | 28 | 25 | 22 | 19 | 22.3 |
Tel Aviv[62] | 18 | 17 | 17 | 18 | 21 | 24 | 27 | 28 | 28 | 26 | 23 | 20 | 22.3 |
Alexandria[63] | 18 | 17 | 17 | 18 | 20 | 23 | 25 | 26 | 26 | 25 | 22 | 20 | 21.4 |
Being nearly landlocked affects conditions in the Mediterranean Sea: for instance, tides are very limited as a result of the narrow connection with the Atlantic Ocean. The Mediterranean is characterised and immediately recognised by its deep blue colour.
Evaporation greatly exceeds precipitation and river runoff in the Mediterranean, a fact that is central to the water circulation within the basin.[64] Evaporation is especially high in its eastern half, causing the water level to decrease and salinity to increase eastward.[65] The average salinity in the basin is 38 PSU at 5 m depth.[66]The temperature of the water in the deepest part of the Mediterranean Sea is 13.2 °C (55.8 °F).[66]
The net water influx from the Atlantic Ocean is ca. 70,000 m³/s or 2.2×1012 m3/a (7.8×1013 cu ft/a).[67] Without this Atlantic water, the sea level of the Mediterranean Sea would fall at a rate of about 1 m per year.[68]
Water circulation in the Mediterranean can be attributed to the surface waters entering from the Atlantic through the Strait of Gibraltar (and also low salinity water entering the Mediterranean from the Black Sea through the Bosphorus). The cool and relatively low-salinity Atlantic water circulates eastwards along the North African coasts. A part of the surface water does not pass the Strait of Sicily, but deviates towards Corsica before exiting the Mediterranean. The surface waters entering the eastern Mediterranean basin circulate along the Libyan and Israeli coasts. Upon reaching the Levantine Sea, the surface waters having warmed and increased its salinity from its initial Atlantic state, is now denser and sinks to form the Levantine Intermediate Waters (LIW). Most of the water found anywhere between 50 and 600 m deep in the Mediterranean originates from the LIW.[69] LIW are formed along the coasts of Turkey and circulate westwards along the Greek and South Italian coasts. LIW are the only waters passing the Sicily Strait westwards. After the Strait of Sicily, the LIW waters circulate along the Italian, French and Spanish coasts before exiting the Mediterranean through the depths of the Strait of Gibraltar. Deep water in the Mediterranean originates from three main areas: the Adriatic Sea, from which most of the deep water in the eastern Mediterranean originates, the Aegean Sea, and the Gulf of Lion. Deep water formation in the Mediterranean is triggered by strong winter convection fueled by intense cold winds like the Bora. When new deep water is formed, the older waters mix with the overlaying intermediate waters and eventually exit the Mediterranean. The residence time of water in the Mediterranean is approximately 100 years, making the Mediterranean especially sensitive to climate change.[70]
Being a semi-enclosed basin, the Mediterranean experiences transitory events that can affect the water circulation on short time scales. In the mid 1990s, the Aegean Sea became the main area for deep water formation in the eastern Mediterranean after particularly cold winter conditions. This transitory switch in the origin of deep waters in the eastern Mediterranean was termed Eastern Mediterranean Transient (EMT) and had major consequences on water circulation of the Mediterranean.[71][72][73]
Another example of a transient event affecting the Mediterranean circulation is the periodic inversion of the North Ionian Gyre, which is an anticyclonic ocean gyre observed in the northern part of the Ionian Sea, off the Greek coast. The transition from anticyclonic to cyclonic rotation of this gyre changes the origin of the waters fueling it; when the circulation is anticyclonic (most common), the waters of the gyre originate from the Adriatic Sea. When the circulation is cyclonic, the waters originate from the Levantine Sea. These waters have different physical and chemical characteristics, and the periodic inversion of the North Ionian Gyre (called Bimodal Oscillating System or BiOS) changes the Mediterranean circulation and biogeochemistry around the Adriatic and Levantine regions.[74]
Because of the short residence time of waters, the Mediterranean Sea is considered a hot-spot for climate change effects.[75] Deep water temperatures have increased by 0.12 °C (0.22 °F) between 1959 and 1989.[76] According to climate projections, the Mediterranean Sea could become warmer. The decrease in precipitation over the region could lead to more evaporation ultimately increasing the Mediterranean Sea salinity.[75][77] Because of the changes in temperature and salinity, the Mediterranean Sea may become more stratified by the end of the 21st century, with notable consequences on water circulation and biogeochemistry.
In spite of its great biodiversity, concentrations of chlorophyll and nutrients in the Mediterranean Sea are very low, making it one of the most oligotrophic ocean regions in the world. The Mediterranean Sea is commonly referred to as an LNLC (Low-Nutrient, Low-Chlorophyll) area. The Mediterranean Sea fits the definition of a desert in which its nutrient contents are low, making it difficult for plants and animals to develop.
There are steep gradients in nutrient concentrations, chlorophyll concentrations and primary productivity in the Mediterranean. Nutrient concentrations in the western part of the basin are about double the concentrations in the eastern basin. The Alboran Sea, close to the Strait of Gibraltar, has a daily primary productivity of about 0.25 g C (grams of carbon) m−2 day−1 whereas the eastern basin has an average daily productivity of 0.16 g C m−2 day−1.[78] For this reason, the eastern part of the Mediterranean Sea is termed "ultraoligotrophic". The productive areas of the Mediterranean Sea are few and small. High (i.e. more than 0.5 grams of Chlorophyll a per cubic meter) productivity occurs in coastal areas, close to the river mouths which are the primary suppliers of dissolved nutrients. The Gulf of Lion has a relatively high productivity because it is an area of high vertical mixing, bringing nutrients to the surface waters that can be used by phytoplankton to produce Chlorophyll a.[79]
Primary productivity in the Mediterranean is also marked by an intense seasonal variability. In winter, the strong winds and precipitation over the basin generate vertical mixing, bringing nutrients from the deep waters to the surface, where phytoplankton can convert it into biomass.[80] However, in winter, light may be the limiting factor for primary productivity. Between March and April, spring offers the ideal trade-off between light intensity and nutrient concentrations in surface for a spring bloom to occur. In summer, high atmospheric temperatures lead to the warming of the surface waters. The resulting density difference virtually isolates the surface waters from the rest of the water column and nutrient exchanges are limited. As a consequence, primary productivity is very low between June and October.[81][79]
Oceanographic expeditions uncovered a characteristic feature of the Mediterranean Sea biogeochemistry: most of the chlorophyll production does not occur on the surface, but in sub-surface waters between 80 and 200 meters deep.[82] Another key characteristic of the Mediterranean is its high nitrogen-to-phosphorus ratio (N:P). Redfield demonstrated that most of the world's oceans have an average N:P ratio around 16. However, the Mediterranean Sea has an average N:P between 24 and 29, which translates a widespread phosphorus limitation.[clarification needed][83][84][85][86]
Because of its low productivity, plankton assemblages in the Mediterranean Sea are dominated by small organisms such as picophytoplankton and bacteria.[87][88]
The geologic history of the Mediterranean Sea is complex. Underlain by oceanic crust, the sea basin was once thought to be a tectonic remnant of the ancient Tethys Ocean; it is now known to be a structurally younger basin, called the Neotethys, which was first formed by the convergence of the African and Eurasian plates during the Late Triassic and Early Jurassic. Because it is a near-landlocked body of water in a normally dry climate, the Mediterranean is subject to intensive evaporation and the precipitation of evaporites. The Messinian salinity crisis started about six million years ago (mya) when the Mediterranean became landlocked, and then essentially dried up. There are salt deposits accumulated on the bottom of the basin of more than a million cubic kilometres—in some places more than three kilometres thick.[89][90]
Scientists estimate that the sea was last filled about 5.3 million years ago (mya) in less than two years by the Zanclean flood. Water poured in from the Atlantic Ocean through a newly breached gateway now called the Strait of Gibraltar at an estimated rate of about three orders of magnitude (one thousand times) larger than the current flow of the Amazon River.[91]
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: the Western Mediterranean, with an area of about 850,000 km2 (330,000 mi2); and the Eastern Mediterranean, of about 1.65 million km2 (640,000 mi2). Coastal areas have submarine karst springs or vruljas, which discharge pressurised groundwater into the water from below the surface; the discharge water is usually fresh, and sometimes may be thermal.[92][93]
This section does not cite any sources.(October 2018) |
The Mediterranean basin and sea system was established by the ancient African-Arabian continent colliding with the Eurasian continent. As Africa-Arabia drifted northward, it closed over the ancient Tethys Ocean which had earlier separated the two supercontinents Laurasia and Gondwana. At about that time in the middle Jurassic period (roughly 170 million years ago[dubious
]) a much smaller sea basin, dubbed the Neotethys, was formed shortly before the Tethys Ocean closed at its western (Arabian) end. The broad line of collisions pushed up a very long system of mountains from the Pyrenees in Spain to the Zagros Mountains in Iran in an episode of mountain-building tectonics known as the Alpine orogeny. The Neotethys grew larger during the episodes of collisions (and associated foldings and subductions) that occurred during the Oligocene and Miocene epochs (34 to 5.33 mya); see animation: Africa-Arabia colliding with Eurasia. Accordingly, the Mediterranean basin consists of several stretched tectonic plates in subduction which are the foundation of the eastern part of the Mediterranean Sea. Various zones of subduction contain the highest oceanic ridges, east of the Ionian Sea and south of the Aegean. The Central Indian Ridge runs east of the Mediterranean Sea south-east across the in-between[clarification needed] of Africa and the Arabian Peninsula into the Indian Ocean.During Mesozoic and Cenozoic times, as the northwest corner of Africa converged on Iberia, it lifted the Betic-Rif mountain belts across southern Iberia and northwest Africa. There the development of the intramontane Betic and Rif basins created two roughly parallel marine gateways between the Atlantic Ocean and the Mediterranean Sea. Dubbed the Betic and Rifian corridors, they gradually closed during the middle and late Miocene: perhaps several times.[94] In the late Miocene the closure of the Betic Corridor triggered the so-called "Messinian salinity crisis" (MSC), when the Mediterranean almost entirely dried out. The start of the MSC was recently estimated astronomically at 5.96 mya, and it persisted for some 630,000 years until about 5.3 mya;[95] see Animation: Messinian salinity crisis, at right.
After the initial drawdown[clarification needed] and re-flooding, there followed more episodes—the total number is debated—of sea drawdowns and re-floodings for the duration of the MSC. It ended when the Atlantic Ocean last re-flooded the basin—creating the Strait of Gibraltar and causing the Zanclean flood—at the end of the Miocene (5.33 mya). Some research has suggested that a desiccation-flooding-desiccation cycle may have repeated several times, which could explain several events of large amounts of salt deposition.[96][97] Recent studies, however, show that repeated desiccation and re-flooding is unlikely from a geodynamic point of view.[98][99]
The present-day Atlantic gateway, the Strait of Gibraltar, originated in the early Pliocene via the Zanclean Flood. As mentioned, there were two earlier gateways: the Betic Corridor across southern Spain and the Rifian Corridor across northern Morocco. The Betic closed about 6 mya, causing the Messinian salinity crisis (MSC); the Rifian or possibly both gateways closed during the earlier Tortonian times, causing a "Tortonian salinity crisis" (from 11.6 to 7.2 mya), long before the MSC and lasting much longer. Both "crises" resulted in broad connections between the mainlands of Africa and Europe, which allowed migrations of flora and fauna—especially large mammals including primates—between the two continents. The Vallesian crisis indicates a typical extinction and replacement of mammal species in Europe during Tortonian times following climatic upheaval and overland migrations of new species:[100] see Animation: Messinian salinity crisis (and mammal migrations), at right.
The almost complete enclosure of the Mediterranean basin has enabled the oceanic gateways to dominate seawater circulation and the environmental evolution of the sea and basin. Circulation patterns are also affected by several other factors—including climate, bathymetry, and water chemistry and temperature—which are interactive and can induce precipitation of evaporites. Deposits of evaporites accumulated earlier in the nearby Carpathian foredeep during the Middle Miocene, and the adjacent Red Sea Basin (during the Late Miocene), and in the whole Mediterranean basin (during the MSC and the Messinian age). Many diatomites are found underneath the evaporite deposits, suggesting a connection between their[clarification needed] formations.
Today, evaporation of surface seawater (output) is more than the supply (input) of fresh water by precipitation and coastal drainage systems, causing the salinity of the Mediterranean to be much higher than that of the Atlantic—so much so that the saltier Mediterranean waters sink below the waters incoming from the Atlantic, causing a two-layer flow across the Strait of Gibraltar: that is, an outflow submarine current of warm saline Mediterranean water, counterbalanced by an inflow surface current of less saline cold oceanic water from the Atlantic. In the 1920s, Herman Sörgel proposed the building of a hydroelectric dam (the Atlantropa project) across the Straits, using the inflow current to provide a large amount of hydroelectric energy. The underlying energy grid was also intended to support a political union between Europe and, at least, the Maghreb part of Africa (compare Eurafrika for the later impact and Desertec for a later project with some parallels in the planned grid).[101]
The end of the Miocene also marked a change in the climate of the Mediterranean basin. Fossil evidence from that period reveals that the larger basin had a humid subtropical climate with rainfall in the summer supporting laurel forests. The shift to a "Mediterranean climate" occurred largely within the last three million years (the late Pliocene epoch) as summer rainfall decreased. The subtropical laurel forests retreated; and even as they persisted on the islands of Macaronesia off the Atlantic coast of Iberia and North Africa, the present Mediterranean vegetation evolved, dominated by coniferous trees and sclerophyllous trees 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.
Because of its latitude and its landlocked position, the Mediterranean is especially sensitive to astronomically induced climatic variations, which are well documented in its sedimentary record. Since the Mediterranean is subject to 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. 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 past geomagnetic reversals.[102] Furthermore, the exceptional accuracy of these paleoclimatic records has improved our knowledge of the Earth's orbital variations in the past.
Unlike the vast multidirectional ocean currents in open oceans within their respective oceanic zones; biodiversity in the Mediterranean Sea is that of a stable one due to the subtle but strong locked nature of currents which affects favorably, even the smallest macroscopic type of volcanic life form. The stable marine ecosystem of the Mediterranean Sea and sea temperature provides a nourishing environment for life in the deep sea to flourish while assuring a balanced aquatic ecosystem excluded from any external deep oceanic factors. It is estimated that there are more than 17,000 marine species in the Mediterranean Sea with generally higher marine biodiversity in coastal areas, continental shelves, and decreases with depth.[103]
As a result of the drying of the sea during the Messinian salinity crisis,[104] the marine biota of the Mediterranean are derived primarily from the Atlantic Ocean. 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. The Alboran Sea has the largest population of bottlenose 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. The Mediterranean monk seals live in the Aegean Sea in Greece. In 2003, the World Wildlife Fund raised concerns about the widespread drift net fishing endangering populations of dolphins, turtles, and other marine animals such as the spiny squat lobster.
There was a resident population of killer whale in the Mediterranean until the 1980s, when they went extinct, probably due to longterm PCB exposure. There are still annual sightings of killer whale vagrants.[105]
For 4,000 years, human activity has transformed most parts of Mediterranean Europe, and the "humanisation of the landscape" overlapped with the appearance of the present Mediterranean climate.[106] The image of a simplistic, environmental determinist notion of a Mediterranean paradise on Earth in antiquity, which was destroyed by later civilisations, dates back to at least the 18th century and was for centuries fashionable in archaeological and historical circles. Based on a broad variety of methods, e.g. historical documents, analysis of trade relations, floodplain sediments, pollen, tree-ring and further archaeometric analyses and population studies, Alfred Thomas Grove's and Oliver Rackham's work on "The Nature of Mediterranean Europe" challenges this common wisdom of a Mediterranean Europe as a "Lost Eden", a formerly fertile and forested region, that had been progressively degraded and desertified by human mismanagement.[106] The belief stems more from the failure of the recent landscape to measure up to the imaginary past of the classics as idealised by artists, poets and scientists of the early modern Enlightenment.[106]
The historical evolution of climate, vegetation and landscape in southern Europe from prehistoric times to the present is much more complex and underwent various changes. For example, some of the deforestation had already taken place before the Roman age. While in the Roman age large enterprises such as the latifundia took effective care of forests and agriculture, the largest depopulation effects came with the end of the empire. Some[who?] assume that the major deforestation took place in modern times—the later usage patterns were also quite different e.g. in southern and northern Italy. Also, the climate has usually been unstable and there is evidence of various ancient and modern "Little Ice Ages",[107] and plant cover accommodated to various extremes and became resilient to various patterns of human activity.[106]
Human activity was therefore not the cause of climate change but followed it.[106] The wide ecological diversity typical of Mediterranean Europe is predominantly based on human behavior, as it is and has been closely related human usage patterns.[106] The diversity range[clarification needed] was enhanced by the widespread exchange and interaction of the longstanding and highly diverse local agriculture, intense transport and trade relations, and the interaction with settlements, pasture and other land use. The greatest human-induced changes, however, came after World War II, in line with the "1950s syndrome"[108] as rural populations throughout the region abandoned traditional subsistence economies. Grove and Rackham suggest that the locals left the traditional agricultural patterns and instead became scenery-setting agents[clarification needed] for tourism. This resulted in more uniform, large-scale formations[of what?].[106] Among further current important threats to Mediterranean landscapes are overdevelopment of coastal areas, abandonment of mountains and, as mentioned, the loss of variety via the reduction of traditional agricultural occupations.[106]
The region has a variety of geological hazards which have closely interacted with human activity and land use patterns. Among others, in the eastern Mediterranean, the Thera eruption, dated to the 17th or 16th century BC, caused a large tsunami that some experts hypothesise devastated the Minoan civilisation on the nearby island of Crete, further leading some to believe that this may have been the catastrophe that inspired the Atlantis legend.[109] Mount Vesuvius is the only active volcano on the European mainland, while others, Mount Etna and Stromboli, are on neighbouring islands. The region around Vesuvius including the Phlegraean Fields Caldera west of Naples are quite active[110] and constitute the most densely populated volcanic region in the world where an eruptive event may occur within decades.[111]
Vesuvius itself is regarded as quite dangerous due to a tendency towards explosive (Plinian) eruptions.[112] It is best known for its eruption in AD 79 that led to the burying and destruction of the Roman cities of Pompeii and Herculaneum.
The large experience[clarification needed] of member states and regional authorities has led to exchange[of what?] on the international level with cooperation of NGOs, states, regional and municipality authorities and private persons.[113] The Greek–Turkish earthquake diplomacy is a quite positive example of natural hazards leading to improved relations between traditional rivals in the region after earthquakes in İzmir and Athens in 1999. The European Union Solidarity Fund (EUSF) was set up to respond to major natural disasters and express European solidarity to disaster-stricken regions within all of Europe.[114] The largest amount of funding requests in the EU relates to forest fires, followed by floods and earthquakes. Forest fires, whether man made or natural, are a frequent and dangerous hazard in the Mediterranean region.[113] Tsunamis are also an often underestimated hazard in the region. For example, the 1908 Messina earthquake and tsunami took more than 123,000 lives in Sicily and Calabria and was among the most deadly natural disasters in modern Europe.
The opening of the Suez Canal in 1869 created the first salt-water passage between the Mediterranean and the Red Sea. The Red Sea is higher than the Eastern Mediterranean, so the canal functions as a tidal strait that pours Red Sea water into the Mediterranean. The Bitter 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, but as the salinity of the lakes gradually equalised 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. 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 ("red") 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, making conditions there even more like the Red Sea and worsening the impact of the invasive 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. A first look at some groups of exotic species shows 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,[115] introduced into the Mediterranean through the Suez Canal. This makes the Canal the first pathway of arrival of alien species into the Mediterranean. 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, 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. 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. 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. 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, and lead to even more species passing through the canal.[116]
In recent decades, the arrival of exotic species from the tropical Atlantic has become noticeable. 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; 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 may be of scientific interest and may therefore[non sequitur] warrant increased levels of monitoring.[citation needed]
By 2100 the overall level of the Mediterranean could rise between 3 to 61 cm (1.2 to 24.0 in) as a result of the effects of climate change.[117] This could have adverse effects on populations across the Mediterranean:
Coastal ecosystems also appear to be threatened by sea level rise, especially enclosed seas such as the Baltic, the Mediterranean and the Black Sea. These seas have only small and primarily east–west movement corridors, which may restrict northward displacement of organisms in these areas.[121] 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.[122]
Pollution in this region has been extremely high in recent years.[when?] 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.[123] 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.'[124]Many marine species have been almost wiped out because of the sea's pollution. One of them is the Mediterranean monk seal which is considered to be among the world's most endangered marine mammals.[125]
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; an average of 1,935 items per km2. Plastic debris accounted for 76%, of which 94% was plastic bags.[126]
Some of the world's busiest shipping routes are in the Mediterranean Sea. In particular, the Maritime Silk Road from Asia and Africa leads through the Suez Canal directly into the Mediterranean Sea to its deep-water ports in Piraeus, Trieste, Genoa, Marseilles and Barcelona. 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. 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 17% of global marine oil pollution. 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 250–300 oil tankers crossing the sea every day. An important destination is the Port of Trieste, the starting point of the Transalpine Pipeline, which covers 40% of Germany's oil demand (100% of the federal states of Bavaria and Baden-Württemberg), 90% of Austria and 50% of the Czech Republic.[127] 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.[122]
The coast of the Mediterranean has been used for tourism since ancient times, as the Roman villa buildings on the Amalfi Coast or in Barcola show. From the end of the 19th century, in particular, the beaches became places of longing for many Europeans and travelers. From then on, and especially after World War II, mass tourism to the Mediterranean began with all its advantages and disadvantages. While initially the journey was by train and later by bus or car, today the plane is increasingly used.[130]
Tourism is today one of the most important sources of income for many Mediterranean countries, despite the man-made geopolitical conflicts[clarification needed] in the region. The countries have tried to extinguish rising man-made chaotic zones[clarification needed] that might affect the region's economies and societies in neighboring coastal countries, and shipping routes. Naval and rescue components in the Mediterranean Sea are considered to be among the best[citation needed] due to the rapid cooperation between various naval fleets. Unlike the vast open oceans, the sea's closed position facilitates effective naval and rescue missions[citation needed], considered the safest[citation needed] and regardless of[clarification needed] any man-made or natural disaster.
Tourism is a source of income for small coastal communities, including islands, independent of urban centers. However, tourism has also played major role in the degradation of the coastal and marine environment. Rapid development has been encouraged by Mediterranean governments to support the large numbers of tourists visiting the region; but this has caused serious disturbance to marine habitats by erosion and pollution in many places along the Mediterranean coasts.
Tourism often concentrates in areas of high natural wealth[clarification needed], causing a serious threat to the habitats of endangered species such as sea turtles and monk seals. Reductions in natural wealth may reduce the incentive for tourists to visit.[122]
Fish stock levels in the Mediterranean Sea are alarmingly low. The European Environment Agency says that more than 65% of all fish stocks in the region are outside safe biological limits and the United Nations Food and Agriculture Organisation, that some of the most important fisheries—such as albacore and bluefin tuna, hake, marlin, swordfish, red mullet and sea bream—are threatened.[date missing]
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.
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.
Beach of Hammamet, Tunisia
The beach of la Courtade in the Îles d'Hyères, France
Sardinia's south coast, Italy
Pretty Bay, Malta
Panoramic view of Piran, Slovenia
Panoramic view of Cavtat, Croatia
View of Neum, Bosnia and Herzegovina
A view of Sveti Stefan, Montenegro
Ksamil Islands, Albania
Navagio, Greece
Marmaris, Turquoise Coast, Turkey
Paphos, Cyprus
Burj Islam Beach, Latakia, Syria
A view of Raouché off the coast of Beirut, Lebanon
A view of Haifa, Israel
Coast of Alexandria, view From Bibliotheca Alexandrina, Egypt
Old city of Ibiza Town, Spain
Les Aiguades near Béjaïa, Algeria
El Jebha, a port town in Morocco
Europa Point, Gibraltar
Panoramic view of La Condamine, Monaco
Sunset at the Deir al-Balah beach, Gaza Strip
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