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Mediterranean-type climates are defined by temperate, wet winters and warm or hot dry 32 summers. The definition originates in the Mediterranean region itself. Here winter storms 33 bring precipitation but the subtropical location ensures cold temperatures rarely occur and 34 the precipitation is generally rain except at high elevations. The summers are dry, apart from 35 localized regions of convection over land, and the subtropical location and clear skies under 36 descending air allow for high temperatures. The dynamical origins of the Mediterranean 37 climate are, in winter, its location at the poleward edge of the winter Hadley Cell and 38 equatorward flank of the North Atlantic storm track and, in summer, its location under 39 a vast area of subsidence extending from the North Atlantic subtropical high, across the 40 Mediterranean and into east Asia and encompassing North Africa as well. 41 Because of the location of the Mediterranean climate and its generation in terms of 42 planetary scale dynamics, it is not surprising that there are four other regions of the world 43 with Mediterranean-type climates. These are the west coast of North America from north-44 ern Mexico to Washington State, central Chile, the far southwest tip of southern Africa 45 and southwest Australia. All these regions have the same winter-dominated precipitation 46 regime, temperate winter climates and hot or warm, dry summers. The climatological sim-47 ilarity of the world’s Mediterranean-type climate regions (MCRs) translates into similar 48 natural vegetation with sparse woodlands, grasses and shrubs that have been converted into 49 similar agricultural uses for …