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( Arid)
In general terms, the climate of a local or region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life. As a result, environments subject to arid climates tend to lack vegetation and are called xeric or desertic. The expression 'available water' refers to water in the soil in excess to the wilting point. The air over a hot desert may actually contain substantial amounts of water vapor but that water may not be generally accessible to plants, except for very specialized organisms (such as some species of lichen). 'Lack of water' refers to use by plants. The water that is actually present in the environment may be sufficient for some species or usages (such as climax vegetation), and grossly insufficient for others. Aridity, the characteristic nature of arid climates, may thus depend on the use of the land. Regards to the presence of life, what is more important than the degree of rainfall is the fraction of precipitation that is not quickly lost through evaporation or runoff. Attempts to quantitatively describe the degree of aridity of a place has often led to the development of aridity indexes. There is no universal agreement on the precise boundaries between classes such as 'hyper-arid', 'arid', 'semi-arid', etc. If different classification schemes and maps differ in their details, there is a general agreement about the fact that large areas of the Earth are considered arid. These include the hot deserts located broadly in sub-tropical regions, where the accumulation of water is largely prevented by either low precipitations, or high evaporation, or both, as well as cold deserts near the poles, where water may be permanently locked in solid forms (snow and ice). Other arid regions include areas located in the rain shadows of major mountain ranges or along coastal regions affected by significant upwelling (such as the Atacama Desert). The distribution of aridity observed at any one point in time is largely the result of the general circulation of the atmosphere. The latter does change significantly over time through climate change. In addition, changes in land use can result in greater demands on soil water and induce a higher degree of aridity. See aridification.
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Arid Subcategories
Arid Articles
Yoga Travel and Tour by Himalayam org
Himalayam believe that the real potential of Uttarakhand is still only in some measure explored and the place has much more to offer than what has been discovered already. One side the place boasts of a rich and diverse flora and fauna to incite an i...
Carbohydrates Play an Important Role in Weight Loss by Michael Podlesny
There are so many fad diets on the market today. Many have you eliminate carbohydrates from your diet all together. However carbohydrates play an important role in weight loss. Your muscles need carbohydrates for energy and to rebuild. As your muscle...
Glyconutrients: Carbohydrates That You Need by Spencer Hunt
Have you had your carbohydrates today?
Since it has only been in the last 100 years that discoveries have led to the realization of vitamins, minerals, and antioxidants… experts agree that there is much more to be lear...
Carbohydrates: So Simple Yet So Complex by Marc David
Copyright 2006 Marc David
The further on your read, you'll begin to understand that everyone needs energy and the best source of energy is from carbohydrates. Roughly 50%-80% of your nutritional intake should come from carbohydrates! (not inclu...
What do Glyconutrients,Polysaccharides and Cell Communicators Have in Common? by Ann Stewart
Answer: they are one and the same! A rose by a different name...! All this mumbo-jumbo about Latin and Greek therapeutic terminologies had been going way over my head for a while. But, suddenly the light lit! Since trying a wonderful produ...
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