A drought (or drouth [archaic]) is an extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that is pulled down by gravity and deposited on the Earth's surface. The main forms of precipitation include rain, snow, ice pellets, and graupel. It occurs when the atmosphere, a large gaseous solution, becomes saturated with water vapour and the water. It can have a substantial impact on the ecosystem An ecosystem consists of all the organisms living in a particular area, as well as all the nonliving, physical components of the environment with which the organisms interact, such as air, soil, water, and sunlight. It is all the organisms in a given area, along with the nonliving factors with which they interact; a biological community and its and agriculture Agriculture is the production of food and goods through farming. Agriculture was the key development that led to the rise of human civilization, with the husbandry of domesticated animals and plants creating food surpluses that enabled the development of more densely populated and stratified societies. The study of agriculture is known as of the affected region. Although droughts can persist for several years, even a short, intense drought can cause significant damage[1] and harm the local economy An economy consists of the economic system of a country or other area, the labor, capital and land resources, and the economic agents that socially participate in the production, exchange, distribution, and consumption of goods and services of that area. A given economy is the end result of a process that involves its technological evolution,.[2]
This global phenomenon has a widespread impact on agriculture. The United Nations The United Nations Organization or simply United Nations (UN) (Arabic: الأمم المتحدة, French: Organisation des Nations Unies, Chinese: 联合国 / 聯合國, Spanish: Organización de las Naciones Unidas, Russian: Организация Объединённых Наций) Filipino: Organisasyon ng Nagkakaisang mga Bansa is an estimates that an area of fertile soil the size of Ukraine Ukraine (pronounced /juːˈkreɪn/ ew-KRAYN; Ukrainian: Україна, transliterated: Ukrayina, [ukrɑˈjinɑ]), with its area of 600,000 sq km, is the second largest country in Eastern Europe. It is bordered by the Russian Federation to the east and northeast, Belarus to the northwest, Poland, Slovakia and Hungary to the west, Romania and is lost every year because of drought, deforestation Deforestation occurs for many reasons: trees or derived charcoal are used as, or sold, for fuel or as a commodity, while cleared land is used as pasture for livestock, plantations of commodities, and settlements. The removal of trees without sufficient reforestation has resulted in damage to habitat, biodiversity loss and aridity. It has adverse, and climate instability.[3] Lengthy periods of drought have long been a key trigger for mass migration and played a key role in a number of ongoing migrations and other humanitarian crises in the Horn of Africa The Horn of Africa (alternatively Northeast Africa, and sometimes Somali Peninsula; shortened to HOA) is a peninsula in East Africa that juts hundreds of kilometers into the Arabian Sea, and lies along the southern side of the Gulf of Aden. It is the easternmost projection of the African continent. Referred to in medieval times as Bilad al Barbar and the Sahel The Sahel is the ecoclimatic and biogeographic zone of transition between the Sahara desert in the North and the Sudanian savannas in the south. It stretches across the north of the African continent between the Atlantic Ocean and the Red Sea. The Sahel covers parts of the countries of Senegal, Mauritania, Mali, Burkina Faso, Algeria, Niger,.
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Consequences
Dry earth in the Sonora desert The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest deserts in North America, with an area of 311,000 square, Mexico In Pre-Columbian Mesoamerica many cultures matured into advanced civilizations such as the Olmec, the Toltec, the Teotihuacan, the Zapotec, the Maya and the Aztec before the first contact with Europeans. In 1521, Spain conquered and colonized the territory, which was administered as the viceroyalty of New Spain which would eventually become Mexico.Periods of drought can have significant environmental, agricultural, health, economic and social consequences. 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 Subsistence agriculture is self-sufficiency farming in which farmers grow only enough food to feed their families. The typical subsistence farm has a range of crops and animals needed by the family to eat during the year. Planting decisions are made with an eye toward what the family will need during the coming year, rather than market prices as a major food source are more vulnerable to drought-triggered famine.
Drought is rarely if ever the sole cause of famine A famine is a widespread scarcity of food that may apply to any faunal species. This phenomenon is usually accompanied by regional malnutrition, starvation, epidemic, and increased mortality; 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 Contamination is the presence of a minor and unwanted constituent in another material, metal, chemical or mixture, often at the trace level. In chemistry, the term usually describes a single chemical, but in specialized fields the term can also mean chemical mixtures, even up to the level of cellular materials of remaining water sources. A few common consequences of drought include:
- Diminished crop growth or yield productions In agriculture, crop yield is not only a measure of the yield of cereal per unit area of land under cultivation, yield is also the seed generation of the plant itself (e.g. one wheat grain produces a stalk yielding three grain, or 1:3).[citation needed][original research?] The figure, 1:3 is considered by agronomists as the minimum required to and carrying capacity for livestock Livestock refers to one or more domesticated animals raised in an agricultural setting to produce commodities such as food, fiber and labor. The term "livestock" as used in this article does not include poultry or farmed fish; however the inclusion of these, especially poultry, within the meaning of "livestock" is common;
- Dust bowls The Dust Bowl or the Dirty Thirties was a period of severe dust storms causing major ecological and agricultural damage to American and Canadian prairie lands from 1930 to 1936 . The phenomenon was caused by severe drought coupled with decades of extensive farming without crop rotation, fallow fields, cover crops or other techniques to prevent, themselves a sign of erosion Erosion is the process of weathering and transport of solids in the natural environment or their source and deposits them elsewhere. It usually occurs due to transport by wind, water, or ice; by down-slope creep of soil and other material under the force of gravity; or by living organisms, such as burrowing animals, in the case of bioerosion, which further erode the landscape Landscape comprises the visible features of an area of land, including the physical elements of landforms, water bodies such as rivers, lakes and the sea, living elements of land cover including indigenous vegetation, human elements including land uses, buildings and structures, and transitory elements such as lighting and weather conditions;
- Dust storms A dust storm or sandstorm is a meteorological phenomenon common in arid and semi-arid regions. Dust storms arise when a gust front blows loose sand and dust from a dry surface. Particles are transported by saltation and suspension, causing soil erosion from one place and deposition in another. The Sahara and drylands around the Arabian peninsula, when drought hits an area suffering from desertification and erosion Erosion is the process of weathering and transport of solids in the natural environment or their source and deposits them elsewhere. It usually occurs due to transport by wind, water, or ice; by down-slope creep of soil and other material under the force of gravity; or by living organisms, such as burrowing animals, in the case of bioerosion;
- Famine A famine is a widespread scarcity of food that may apply to any faunal species. This phenomenon is usually accompanied by regional malnutrition, starvation, epidemic, and increased mortality due to lack of water for irrigation Irrigation is an artificial application of water to the soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall. Additionally, irrigation also has a few other uses in crop production, which include protecting plants;
- Habitat A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism. It is the natural environment in which an organism lives, or the physical environment that surrounds (influences and is utilized by) a species population.[citation needed] damage, affecting both terrestrial An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural communities and species. The biodiversity of flora, fauna and aquatic An aquatic ecosystem is an ecosystem located in a body of water. Communities of organisms that are dependent on each other and on their environment live in aquatic ecosystems. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems wildlife.
- Malnutrition Malnutrition is the insufficient, excessive or imbalanced consumption of nutrients. A number of different nutrition disorders may arise, depending on which nutrients are under or overabundant in the diet, dehydration Dehydration is defined as an excessive loss of body fluid. It is literally the removal of water (Ancient Greek: ὕδωρ hýdōr) from an object, however in physiological terms, it entails a deficiency of fluid within an organism and related diseases;
- Mass migration, resulting in internal displacement Internally displaced persons are people forced to flee their homes but who, unlike refugees, remain within their country's borders. At the end of 2006 estimates of t4.5 million in some 52 countries. The region with the largest IDP population is Africa with some 11.8 million in 21 countries and international refugees Under the United Nations Convention Relating to the Status of Refugees from 1951, a refugee is a person who , "owing to a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group, or political opinion, is outside the country of his nationality, and is unable to or, owing to such;
- Reduced electricity production The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. His basic method is still used today: electricity is generated by the movement of a loop of wire, or disc of copper between the poles of a magnet due to insufficient available coolant for power stations A power station is an industrial facility for the generation of electric power;[4] and reduced water flow through hydroelectric dams A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are often used in conjunction with dams to provide clean.[5]
- Shortages of water for industrial Industry refers to the production of an economic good within an economy. There are four key industrial economic sectors: the primary sector, largely raw material extraction industries such as mining and farming; the secondary sector, involving refining, construction, and manufacturing; the tertiary sector, which deals with services (such as law users;[6][7]
- Snakes Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with many more joints than their lizard ancestors, migration and increases in snakebites;[8]
- Social unrest;
- War War is a behaviour pattern exhibited by many primate species including humans, and also found in many ant species. The primary feature of this behaviour pattern is a certain state of organized violent conflict that is engaged in between two or more separate social entities. Such a conflict is always an attempt at altering either the psychological over natural resources, including water and food;
- Wildfires A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, grass fire, hill fire, peat fire, vegetation fire, veldfire and wildland fire may be used to describe the same phenomenon depending on the type of vegetation being burned. A, such as Australian For at least 40,000 years before European settlement in the late 18th century, Australia was inhabited by indigenous Australians, who belonged to one or more of the roughly 250 language groups. After sporadic visits by fishermen from the immediate north and discovery by Dutch explorers in 1606, Australia's eastern half was claimed by Britain in 177 bushfires A bushfire is a fire that occurs in the bush (collective term for scrub, woodland or grassland of Australia, New Zealand, New Caledonia). In south east Australia, bushfires tend to be most common and most severe during summer and autumn, in drought years, and particularly severe in El Niño years. Southeast Australia is fire prone, and warm and, are more common during times of drought;[9]
Globally
Drought is a normal, recurring feature of the climate in most parts of the world. It is among the earliest documented climatic events, present in the Epic of Gilgamesh The Epic of Gilgamesh is an epic poem from Mesopotamia and is among the earliest known works of literary writing. Scholars believe that it originated as a series of Sumerian legends and poems about the mythological hero-king Gilgamesh, which were gathered into a longer Akkadian epic much later. The most complete version existing today is preserved and tied to the biblical The Bible refers to collections of sacred scripture of Judaism and Christianity. There is no single version: both the individual books and their order vary. The Hebrew Bible contains 24 books that were rearranged into 39 by Christian denominations, while complete Christian Bibles range from the 66 books of the Protestant canon to 81 books in the story of Joseph Joseph or Yosef , was the eleventh son of Jacob and first son of Rachel in the book of Genesis. He is also known as Zaphnath-Paaneah's arrival in and the later Exodus The Exodus (Greek word έξοδος, is the story of the departure of the Israelites from ancient Egypt described in the Hebrew Bible. Narrowly defined, the term refers only to the departure from Egypt described in the Book of Exodus; more widely, it takes in the subsequent wanderings in the wilderness described in the books of Numbers and from Ancient Egypt Ancient Egypt was an ancient civilization of eastern North Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. The civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh, and it developed over the next three millennia. Its history.[10] Hunter-gatherer migrations in 9,500 BC Chile have been linked to the phenomenon, as has the [11] exodus of early man out of Africa In paleoanthropology, the recent African origin of modern humans is the mainstream model describing the origin and early dispersal of anatomically modern humans. The theory is called the Out-of-Africa model in the popular press, and academically the recent single-origin hypothesis (RSOH), Replacement Hypothesis, and Recent African Origin (RAO) and into the rest of the world around 135,000 years ago.[12]
Modern peoples can effectively mitigate much of the impact of drought through irrigation and crop rotation. Failure to develop adequate drought mitigation strategies carries a grave human cost in the modern era, exacerbated by ever-increasing Population growth is the change in a population over time, and can be quantified as the change in the number of individuals of any species in a population using "per unit time" for measurement. In biology, the term population growth is likely to refer to any known organism, but this article deals mostly with the application of the term population densities.
Regions
Lake Chad Lake Chad is a historically large, shallow lake in Africa, whose size has varied over the centuries. According to the UN it shrank as much as by 95 percent from about 1963 to 1998 yet they also state that "The 2007 (satellite) image shows significant improvement over previous years". Lake Chad is economically important, providing water in a 2001 satellite image, with the actual lake in blue. The lake has shrunk by 95% since the 1960s.[13][14] Sheep on a drought affected paddock near Uranquinty, New South Wales New South Wales , Australia's most populous state, is located in the south-east of the country, north of Victoria, south of Queensland, east of South Australia and encompasses the whole of the Australian Capital Territory. It was founded in 1788 and originally comprised much of the Australian mainland, as well as Van Diemen's Land, Lord Howe.Recurring droughts leading to desertification Desertification is the degradation of land in arid and dry sub-humid areas due to various factors: including climatic variations and human activities. Desertification results chiefly from man-made activities[citation needed]: it is principally caused by overgrazing, overdrafting of groundwater and diversion of water from rivers for human in the Horn of Africa The Horn of Africa (alternatively Northeast Africa, and sometimes Somali Peninsula; shortened to HOA) is a peninsula in East Africa that juts hundreds of kilometers into the Arabian Sea, and lies along the southern side of the Gulf of Aden. It is the easternmost projection of the African continent. Referred to in medieval times as Bilad al Barbar have created grave ecological catastrophes, prompting massive food shortages, still recurring.[15] To the north-west of the Horn, the Darfur conflict in neighboring Sudan, also affecting Chad, was fueled by decades of drought; combination of drought, desertification and overpopulation are among the causes of the Darfur conflict, because the Arab Baggara nomads searching for water have to take their livestock further south, to land mainly occupied by non-Arab farming peoples.[16]
Approximately 2.4 billion people live in the drainage basin of the Himalayan rivers.[17] India, China, Pakistan, Bangladesh, Nepal and Myanmar could experience floods followed by droughts in coming decades. Drought in India affecting the Ganges is of particular concern, as it provides drinking water and agricultural irrigation for more than 500 million people.[18][19][20] The west coast of North America, which gets much of its water from glaciers in mountain ranges such as the Rocky Mountains and Sierra Nevada, also would be affected.[21][22]
In 2005, parts of the Amazon basin experienced the worst drought in 100 years.[23][24] A 23 July 2006 article reported Woods Hole Research Center results showing that the forest in its present form could survive only three years of drought.[25][26] Scientists at the Brazilian National Institute of Amazonian Research argue in the article that this drought response, coupled with the effects of deforestation on regional climate, are pushing the rainforest towards a "tipping point" where it would irreversibly start to die. It concludes that the rainforest is on the brink of being turned into savanna or desert, with catastrophic consequences for the world's climate. According to the WWF, the combination of climate change and deforestation increases the drying effect of dead trees that fuels forest fires.[27]
By far the largest part of Australia is desert or semi-arid lands commonly known as the outback. A 2005 study by Australian and American researchers investigated the desertification of the interior, and suggested that one explanation was related to human settlers who arrived about 50,000 years ago. Regular burning by these settlers could have prevented monsoons from reaching interior Australia.[28] In June 2008 it became known that an expert panel had warned of long term, maybe irreversible, severe ecological damage for the whole Murray-Darling basin if it does not receive sufficient water by October.[29] Australia could experience more severe droughts and they could become more frequent in the future, a government-commissioned report said on July 6, 2008.[30] The Australian of the year 2007, environmentalist Tim Flannery, predicted that unless it made drastic changes, Perth in Western Australia could become the world’s first ghost metropolis, an abandoned city with no more water to sustain its population.[31]
East Africa currently faces its worst drought in decades,[32][33] with crops and livestock destroyed.[34] The U.N. World Food Programme recently said that nearly four million Kenyans urgently needed food.[35]
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Wed, 01 Sep 2010 14:08:20 GMT+00:00
Sydney Morning Herald Photo: Brendan Esposito THE drought is broken. In NSW, farmers are preparing to harvest their largest crop - a record $2.8 billion winter yield, ... Out of drought Harden Murrumburrah Express Farmers in clover over $1.8bn wheat harvest The Australian
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California s Assembly members have a chance to show just how worried they are about the state s looming water shortages when the Water Efficiency and Security Act comes up for a vote this
Thu, 24 Apr 2008 00:32:34 PDT
Drought-Proofing our Community by Brad Lancaster. A talk on water harvesting by Brad Lancaster, presented in Asheville, NC, April 20, 2008 ... video.google.com.
Akshita
hu, 02 Sep 2010 16:51:07 GM
Bhubaneswar, Sep 2 - Poor monsoon rains have triggered . drought. fears in half of Orissa, an official said Thursday. 'At least 15 of state's 30 districts have recorded less then normal (averagge) rains,' a senior official of the state ...
