The Mediterranean basin is a unique feature of the Earth’s system for two reasons. Firstly, its geographical position is at the border between two climate regimes, and consequently climate and climate dependent living conditions in the area are very sensitive against even small shifts of this border. Secondly, due to the enclosed large sea, the bizarre coastal structure, and the mountain barriers, it has an extremely complex topography which gives rise to specific local climatic effects and climate gradients. Nowhere in the world is the Mediterranean climate as extended as at the border between Europe, Africa, and the Near East. It covers about 10 million km2, reaching from Portugal to south of the Caspian Sea with a core area that stretches over 46 degrees longitude. This is due to the long latitudinal extent of the Mediterranean basin with an area of about 6 million km2. Of this area, 2,496 million km2 is the surface of the sea.