Mediterranean Climatic Regions
The warm temperate western margin climate or the Mediterranean climate is found between 30o and 45o North and South of the Equator. This climate is witnessed in relatively fewer parts of the world and is almost entirely confined to the western margins of the continental landmasses. The basic cause of this climate is the seasonal shift of the wind belts.
Mediterranean Climatic Regions
- Central Chile,
- California (around San Francisco),
- The southwestern tip of Africa (around Cape Town),
- Southern Australia (in southern Victoria and
- Around Adelaide bordering St, Vincent, and Spencer Gulfs), and south-west Australia (Swanland).
The Mediterranean climate is characterized by very distinctive climatic features with dry, warm summers and wet, cold winters and local winds.
Dry, warm summers with off-shore Tradewinds:
- During the summer months, the sun is overhead the Tropic of Cancer and Tropic of Capricorn.
- The belt of the influence of the Westerlies is shifted polewards, and the rain-bearing tradewinds are likely to be off-shore.
- Hence the regions are practically rainless in summers and hence remain dry.
- The heat is intense and the days are excessively warm.
- In the interiors, prolonged droughts are common. The relative humidity is generally low.
The summer temperatures are relatively high, and the highest temperatures are experienced away from the coast in the continental interiors of the Balkan peninsula, the Anatolian plateau, and the Mediterranean Middle East.
Wet, cold winters with on-shore Westerlies:
- In the winter months, the Westerlies belt shifts equatorward and the Mediterranean regions are under the influence of on-shore Westerlies.
- Hence, these lands receive almost all of their precipitation during the winter months.
- The rain comes in heavy downpours and causes floods in the months of September and October in Mediterranean Europe.
The Mediterranean climatic region in Europe experiences many local winds due to the topography of the region with the Alps in the North, the Sahara desert in the South, the continental interiors in the East and the open Atlantic in the west. These create great differences in temperature, pressure, and precipitation. The two most important local winds are:
- This is a hot, dry and dusty wind.
- It originates in the Sahara desert and might occur at any time of the year but is mostly witnessed during spring.
- Normally it lasts only for a few days.
- It blows from the desert interiors of Sahara into the Mediterranean Sea and is usually associated with the depressions from the Atlantic ocean.
- After crossing the Sea, it is slightly cooled by the absorption of water vapour but is hot enough that it withers vegetation and crops of the region.
- Hence it is also called "Blood Rain" because it is carrying the red dust of the Sahara desert.
- Mistral is a cold wind from the north.
- It rushes down the Rhone valley and its velocity is intensified by the funnelling effect in the valley between the Alps and the Central Massif[Plateau in France].
- In some extreme cases, the velocity of the wind is so high that trains can be derailed and trees are uprooted.
- In winter, if the Mistral is frequent the temperatures could go below the freezing point.
Other local winds
- Bora: Cold north-easterly wind along the Adriatic coast.
- Tramontana and Gregale: cold winds in the Mediterranean Sea.
- The vegetation of the region is not luxuriant.
- Trees are with small broad leaves and are widely spaced.
- The absence of shade is a peculiar feature of this climate and the growth is almost restricted to autumn and spring.
- Plants are in a continuous struggle against heat, dry air, excessive evaporation and prolonged droughts.
- Hence they are generally xerophytic or drought resistant in nature.
Types of Mediterranean vegetation:
- Evergreen forests
- They are found only in climatically suitable regions with rainfall over 25inches and are open woodlands with evergreen oaks.
- The cork oaks are used for making wine-bottle corks.
- In Australia, the eucalyptus forests replace the evergreen oak.
- The giant sequoia or redwood is typical of the Californian trees.
- Evergreen Coniferous forests
- They include various kinds of pines, firs, cedars and cypresses.
- They appear mostly in the cooler highlands and where droughts are not so severe.
- Bushes and Shrubs
- This is the most prominent type of Mediterranean vegetation.
- The low bushes grow in scattered clumps and are often thorny.
- Since most of the rain comes during the cool season when the growth is slow, the conditions of this region do not suit grass.
- They are generally wiry and bunchy and are not suitable for animal farming.
- Thus cattle rearing is not an important occupation in the Mediterranean.
The region is important for fruit cultivation, cereal growing, wine-making and agricultural industries as well as engineering and mining. The region is a net exporter of citrus fruits and the net importer of dairy products.
- Orchard farming
- These regions are known as the world's orchard lands.
- A wide range of citrus fruits grows in the region. Examples: Sunkist oranges of California, Jaffa oranges of Israel.
- The fruit trees have long roots to draw water from depths during the long summer months.
- The olive tree is probably the most typical of all Mediterranean cultivated vegetation.
- Besides these, many nut trees like chestnuts, walnuts, hazelnuts and almonds are grown.
- Other important fruits are peaches, apricots, pears, cherries, plums and figs.
- Crop cultivation
- Cereals are the most important crops and wheat is the leading crop followed by barley.
- Though the climatic conditions are not favourable for the extensive cultivation of wheat, the farmers have utilised the seasonal climatic rhythm to their best advantage.
- Sheep rearing
- The mountain pastures with cooler climate support a few sheep, goats and cattle.
- Transhumance is widely practised in the region.
- Wine production
- Viticulture is speciality and tradition of Mediterranean region.
- The long, sunny summer allows the grapes to ripen.
- Regions bordering the Mediterranean Sea account for three-quarters of the world s production of wine.