Mediterranea Planospiroides

In biogeography, the Mediterranean Basin (; also known as the Mediterranean Region or sometimes Mediterranea) is the region of lands around the Mediterranean Sea that have mostly a Mediterranean climate, with mild to cool, rainy winters and warm to hot, dry summers, which supports characteristic Mediterranean forests, woodlands, and scrub vegetation.

Geography

The Mediterranean Basin covers portions of three continents: Europe, Africa, and Asia. It is distinct from the drainage basin, which extends much further south and north due to major rivers ending in the Mediterranean Sea, such as the Nile and Rhône. Conversely, the Mediterranean Basin includes regions not in the drainage basin.

It has a varied and contrasting topography. The Mediterranean Region offers an ever-changing landscape of high mountains, rocky shores, impenetrable scrub, semi-arid steppes, coastal wetlands, sandy beaches and a myriad islands of various shapes and sizes dotted amidst the clear blue sea. Contrary to the classic sandy beach images portrayed in most tourist brochures, the Mediterranean is surprisingly hilly. Mountains can be seen from almost anywhere.

By definition, the Mediterranean Basin extends from Macaronesia in the west, to the Levant in the east, although some places may or may not be included depending on the view, as is the case with Macaronesia: some definitions only include Madeira and the Canary Islands while others include the whole Macaronesia (with the Azores and Cape Verde).

In Western Asia, it covers the western and southern portions of the peninsula of Anatolia, as far as Iraq, but excluding the temperate-climate mountains of central Turkey. It includes the Mediterranean 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 the Sahara Desert, which extends across North Africa, by the Atlas Mountains. 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.

Europe lies to the north of the Mediterranean. The European portion of the Mediterranean Basin loosely corresponds to Southern Europe. The three large Southern European peninsulas, the Iberian Peninsula, Italian Peninsula, and the Balkan Peninsula, extend into and comprise much of the Mediterranean-climate zone. A system of folded mountains, including the Pyrenees dividing Spain from France, the Alps dividing Italy from Central Europe, the Dinaric Alps along the eastern Adriatic, and the Balkan and Rila-Rhodope mountains of the Balkan Peninsula divide the Mediterranean from the temperate climate regions of Western, Northwestern or Northern Europe, Central Europe, and Eastern Europe.

Geology and paleoclimatology

The Mediterranean Basin was shaped by the ancient collision of the northward-moving African–Arabian continent with the stable Eurasian continent. As Africa–Arabia moved north, it closed the former Tethys Sea, which formerly separated Eurasia from the ancient super continent of Gondwana, of which Africa was part. At about the same time, 170 mya in the Jurassic period, a small Neotethys ocean basin formed shortly before the Tethys Sea was closed at the eastern end. 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. 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 Africa, which caused the entire sea to evaporate. There followed several (debated) episodes of sea drawdown and re-flooding known as the Messinian Salinity Crisis, which ended when the Atlantic last re-flooded the basin at the end of the Miocene. Recent research has suggested that a desiccation-flooding cycle may have repeated several times during the last 630,000 years of the Miocene epoch, which could explain several events of large amounts of salt deposition. Recent studies, however, show that repeated desiccation and re-flooding is unlikely from a geodynamic point of view.

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. The shift to a Mediterranean climate occurred within the last 3.2–2.8 million years, during the Pliocene