Dear All, In preparation for the introduction to the topic of the week I will post today I am posting some background information on Mediterranean climates. I am borrowing heavily from Plant Life in the World's Mediterranean Climates: California, Chile, South Africa, Australia, and the Mediterranean Basin by Peter R. Dallman. The regions of the world with this climate are found in California, Chile, South Africa, Australia, and the Mediterranean Basin. These areas lie between 30 degrees and 45 degrees of latitude with California and the Mediterranean Basin being in the Northern Hemisphere and central Chile, the western Cape and Southwest and South Australia being in the Southern Hemisphere. What these areas have in common is dry summers with sunshine and clear skies. Rainfall is concentrated during the mild, winter half of the year and averages 10-40 inches (25-100 cm) annually. Snow is rare except for high elevations. Rainfall is variable every year and usually comes in storms that may last a few days. Areas closer to the equator are drier and those farther away get more rainfall. For example Southern California is much drier than Northern California and the southwestern part of the Cape much wetter than the areas farther north. Rainfall is typically greater with increased elevation, especially on western slopes that face the ocean. For example, Adelaide, the capital of South Australia near sea level averages 21 inches (53 cm) of rain yearly and Mt Lofty nearby at 2400 foot (727 m) elevation gets twice as much. Between storms the weather in crisp and clear. Summer rains are rare but only two of the regions have areas that are completely dry: California and Chile. Other regions have occasional rainfall even though they get most of their rain in winter. The valleys between the mountains are much drier. The Biedouw Valley in South Africa is quite dry whereas the Cederberg Ranges above it get significantly more rainfall. All of these regions are located on the western or southwestern coasts of continents where there are cold, offshore ocean currents. These oceans have a moderating effect on summer temperatures. But there are exceptions here as well. Southwestern Australia has southward-pflowing offshore currents that are warm and a warmer summer climate. The Mediterranean Sea because it is enclosed by land warms up more so the lands that border it have hotter summers. Lauw spoke of areas that can grow citrus versus areas that are good for olive trees. Areas closer to the oceans are cooler and often have very little variation between summer and winter temperatures. The coastal areas of California experience summer cooling fogs that also provide moisture. In Cape Town the "tablecloth" on table mountain provides cooling temperatures and mists and I believe the same kind of thing happens in the Stirlings in Western Australia. The moderating maritime influence of most of these climate areas give them mild winter temperatures well above freezing even during the coldest month of the year. Geophytes because of their underground food and water storage organs that allow them to cope with the long period of drought are one of the plant adaptations of these climates so a large number are usually found in these areas. Mary Sue PBS List Administrator and TOW Coordinator