About 300 species native to the Red Sea have already been identified in the Mediterranean Sea, and there are probably others yet unidentified. 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 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. The construction of the Aswan High Dam in 1970 put an end to this seasonal fluctuation of the Nile’s discharge into the Mediterranean. The Rifian Corridor closed about six million years ago, allowing exchanges of mammal species between Africa and Europe. In the Mediterranean basin, diatomites are regularly found underneath the evaporitic deposits, suggesting a connection between their geneses.
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. 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. The surface waters entering the eastern Mediterranean Basin circulate along the Libyan and Israeli coasts. In oceanography, it is sometimes called the Eurafrican Mediterranean Sea, the European Mediterranean Sea or the African Mediterranean Sea to distinguish it from mediterranean seas elsewhere, like the Baltic Sea, and the North-east Atlantic Ocean. The sea is divided naturally into western and eastern regions by the Malta Escarpment that runs from the island of Sicily to the African coast. The Mediterranean region has a special climate that can be found in other parts of the world, like South Africa or southeastern Australia.
The Mediterranean Sea has numerous underwater geological features formed by the subduction of the African Plate beneath the Eurasian Plate. As a consequence, the river discharges of the Rhône and Po are similar to that of the Nile, despite the latter having a much larger basin. The basins of the Ebro, Po, and Maritsa, are respectively south of the Pyrenees, Alps, and Balkan Mountains, which are the major ranges bordering Southern Europe.
However, all these species of fishes are threatened with extinction due to severe overfishing. It is believed that when the Persian King Darius I conquered Ancient Egypt, he had built a canal that connected the Mediterranean with the Red Sea. The Mediterranean Sea basin was formed during the Late Triassic and the early Jurassic periods due to the convergence of the African and Eurasian plates.
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 drying of the sea during the Messinian Salinity Crisis eliminated most of the marine life of that period, and the current marine biota of the Mediterranean are derived primarily from the Atlantic Ocean. Water circulation patterns are driven by a number of interactive factors, such as climate and the sea floor terrain, which can lead to precipitation of evaporites. 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. This process brought about profound changes in the oceanic circulation patterns, which shifted global climates toward colder conditions. It is now known to be a structurally younger ocean basin (44 million years) known as Neotethys.
The climate is influenced by the sea, with coastal areas experiencing milder temperatures than inland regions. The sea has served as a backdrop for countless myths and legends—from Odysseus’s epic journey in Homer’s “Odyssey” to the tales of ancient mariners navigating its treacherous waters. The Posidonia oceanica seagrass meadows are particularly noteworthy; they play a crucial role in maintaining water quality and providing habitat for numerous marine organisms. As we delve deeper into the Mediterranean’s geography, climate, biodiversity, human impact, and cultural significance, we uncover the intricate relationships that define this remarkable sea.
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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. The western section has three submarine basins, the Alborán, the Algerian, and the Tyrrhenian basins (from west to east), divided from one another by submerged ridges. In oceanography, the Mediterranean Sea is sometimes called the Eurafrican Mediterranean Sea or the European Mediterranean Sea, to distinguish it from mediterranean seas elsewhere. 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. Nutrient concentrations in the western part of the basin are about double the concentrations in the eastern basin.
The Europeans had a new trade route through the Red Sea to their colonies Asia. However , when Vasco da Gama sailed around Africa during the Age of Exploration the trade route across the Mediterranean to Asia became less important. For hundreds of years the Mediterranean Sea was the main water route. Ancient cultures in Greece, Egypt and Rome and Phoenicia developed along the shores of the Mediterranean region. A small part of the coastal population earns their money by fishing.
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. The Alboran Sea is a transition zone between the two seas, containing a mix of Mediterranean and Atlantic species. The North Atlantic is considerably colder and more nutrient-rich than the Mediterranean, and the marine life of the Mediterranean cocksmoker has had to adapt to its differing conditions in the five million years since the basin was reflooded later. There the development of the intramontane Betic and Rif basins created two roughly parallel marine gateways between the Atlantic Ocean and the Mediterranean Sea.
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. 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. Unlike the vast multidirectional ocean currents in open oceans within their respective oceanic zones; biodiversity in the Mediterranean Sea is stable due to the subtle but strong locked nature of currents which is favourable to life, even the smallest macroscopic type of volcanic life form. 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. 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).
Numerous commercial marine fishes such as bluefin tuna, grouper, sea bass, sardines, anchovy, and hake are also found here. Several studies have indicated that the Mediterranean Sea waters are more saline compared to the waters of the Atlantic. The sea has an average depth of about 1,500 m and a maximum depth of 5,267 m at its deepest point, the Calypso Deep in the Ionian Sea. The Mediterranean Sea extends for about 4,000 km (west to east) from the Strait of Gibraltar to the Gulf of Iskenderun on Turkey’s southwestern coast. The Mediterranean Sea is also often referred to as the “Eurafrican Mediterranean Sea” by oceanographers due to its location between the continents of Asia and Europe. Covering an area of about 2.5 million km2, the Mediterranean Sea is the 10th-largest sea in the world located between Southern Europe and Northern Africa and accounting for about 0.7% of the global ocean area.
High (i.e. more than 0.5 grams of Chlorophyll a per cubic metre) productivity occurs in coastal areas, close to the river mouths which are the primary suppliers of dissolved nutrients. Extreme warming can lead to biodiversity loss and presents an existential threat to some habitats while making conditions more hospitable to invasive tropical species. 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. Deep water formation in the Mediterranean is triggered by strong winter convection fuelled by intense cold winds like the Bora.
The basin of the Rhône is the largest and extends up as far north as the Jura Mountains, encompassing areas even on the north side of the Alps. The basin of the Nile constitutes about two-thirds of the Mediterranean drainage basin and encompasses areas as high as the Ruwenzori Mountains. An Azerbaijani official described the sea as “a burial ground … where people die”. European Parliament president Martin Schulz said in 2014 that Europe’s migration policy “turned the Mediterranean into a graveyard”, referring to the number of drowned refugees in the region as a direct result of the policies.
Historically, large seasonal inflows from the Nile, which reduced the salinity of coastal waters, were part of an essential cycle influencing the hydrology and the productivity of the fisheries of the southeastern part of the Mediterranean. Thus, seawater flow is eastward in the strait’s surface waters, and westward below; once in the open ocean, this chemically-distinct “Mediterranean Intermediate Water” can persist thousands of kilometers away from its source. Moreover, climate change poses an existential threat to marine ecosystems; rising sea temperatures and ocean acidification are altering species distributions and disrupting traditional fishing patterns. Salinity in the surface waters of the Mediterranean is about 38 parts per thousand, except in the area closest to the Atlantic, and approaches 40 parts per thousand in the eastern Mediterranean during the summer. This imbalance causes a pressure gradient which draws 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. A 316 m-deep submarine ridge situated between Sicily and the African coast divides the Mediterranean Sea into eastern and western portions.
Tsunamis, usually triggered by earthquakes, volcanic eruptions and submarine landslides, have caused a number of documented disasters in the Mediterranean Basin in the past 2500 years. In the same region the Phlegraean Fields west of Naples constitute one of the most significant volcanic systems in the world, still very active. The Mediterranean region is one of the most geologically active maritime area of the globe, sitting on a complex tectonic boundary zone between the European and African plates. 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. The diversity rangeclarification 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 wide ecological diversity typical of Mediterranean Europe is predominantly based on human behaviour, as it is and has been closely related to human usage patterns.}
The resulting density difference virtually isolates the surface waters from the rest of the water column and nutrient exchanges are limited. In summer, high atmospheric temperatures lead to the warming of the surface waters. 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.
The Mediterranean is the world’s most important wine-growing region. Although it is very dry during the summer months, farming plays an important role in the region. They all create deltas because there are no currents that carry the water away.
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. These events, mainly driven by a combination of oceanic and atmospheric factors, are often triggered by high pressure systems that will reduce cloud cover and increase solar absorption by the sea surface. Because of the short residence time of its waters, the Mediterranean Sea is considered a hot-spot for climate change records, registering indeed marked increases in temperature across the entire water column since the 1950s.
The Mediterranean Sea is a body of water that is almost completely surrounded by land. Geographical land use is an article discussing the environmental features on Earth and how humans have adapted the environment to … These issues threaten the biodiversity and ecological balance of the region, prompting efforts to promote sustainable development and conservation. The Mediterranean Sea faces several environmental challenges, including pollution, overfishing, habitat destruction, and climate change. The region is also rich in natural resources such as oil and gas, which contribute to its economic significance.