Drought

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A drought is a period of time when there is not enough water to support agricultural, urban, human, or environmental water needs. A drought usually refers to an extended period of below-normal rainfall, but can also be caused by drying bores or lakes, or anything that reduces the amount of liquid water available. Although what is considered "normal" varies from one region to another, drought is a recurring feature of nearly all the world's climatic regions. The effects of drought vary greatly, depending on agricultural, urban and environmental water needs. Water companies, farmers, and ranchers are those that suffer the worst as a result of drought.

1 Definitions
2 Consequences
3 Main mitigation strategies
4 See also
5 References

[edit] Definitions

Fields outside Benambra, Victoria suffering from drought conditions

Conceptually, there are three main types of drought:

Meteorological drought is brought about when there is a prolonged period with less than average precipitation. Meteorological drought usually precedes the other kinds of drought.
Agricultural drought is brought about when there is insufficient moisture for crop or range production. This condition can arise, even in times of average precipitation, owing to soil conditions or agricultural techniques.

Hydrological drought is brought about when the water reserves available in sources such as aquifers, lakes, and reservoirs falls below the statistical average. This condition can arise, even in times of average (or above average) precipitation, when increased usage of water diminishes the reserves.

[edit] Consequences

Periods of drought can have significant environmental, economic and social consequences. The most common consequences are:

Wildfires (called Bushfires in Australia and New Zealand)
Ground drag and Desertification.
Malnutrition, dehydration and related diseases
Famine due to lack of water for irrigation
Social unrest
Mass migration, resulting in internal displacement and international refugees
War for water and foods.

The effect varies according to vulnerability. For example, subsistence farmers are more likely to migrate during drought because they do not have alternative food sources. Areas with populations that depend on subsistence farming as a major food source are more vulnerable to drought-triggered famine. Drought is rarely if ever the sole cause of famine; socio-political factors such as extreme widespread poverty play a major role.

Drought can also reduce water quality, because lower water flows reduce dilution of pollutants and increase contamination of remaining water sources in that

[edit] Main mitigation strategies

The main mitigation strategies are as follows-

Drought monitoring-- It is a continuous observation of rainfall situation and comparison with the existing water needs of a particular sector of a society.
Water supply conservation-- We can conserve water through Rain Water Harvesting which can be used for agricultural purposes.
Land use-- Crops which needs less water should be grown in a drought prone area.
Livelihood planning- A section of a society which is least affected by the droughts should be advised to live there.