document_title: Cotton

question_text: who produces the most cotton in the us

question_tokens: who produces the most cotton in the us

text: Cotton

text: Types

text: There are four commercially grown species of cotton, all domesticated in antiquity:

text:
Gossypium hirsutum – upland cotton, native to Central America, Mexico, the Caribbean and southern Florida (90% of world production)
Gossypium barbadense – known as extra-long staple cotton, native to tropical South America (8% of world production)
Gossypium arboreum – tree cotton, native to India and Pakistan (less than 2%)
Gossypium herbaceum – Levant cotton, native to southern Africa and the Arabian Peninsula (less than 2%)

text: The two New World cotton species account for the vast majority of modern cotton production, but the two Old World species were widely used before the 1900s. While cotton fibers occur naturally in colors of white, brown, pink and green, fears of contaminating the genetics of white cotton have led many cotton-growing locations to ban the growing of colored cotton varieties.

text: History

text: Early history

text: Indian subcontinent

text: The earliest evidence of cotton use in the Indian subcontinent has been found at the site of Mehrgarh and Rakhigarhi where cotton threads have been found preserved in copper beads; these finds have been dated to Neolithic (between 6000 and 5000 BC).[4][5] Cotton cultivation in the region is dated to the Indus Valley Civilization, which covered parts of modern eastern Pakistan and northwestern India between 3300 and 1300 BC.[6] The Indus cotton industry was well-developed and some methods used in cotton spinning and fabrication continued to be used until the industrialization of India.[7] Between 2000 and 1000 BC cotton became widespread across much of India.[8] For example, it has been found at the site of Hallus in Karnataka dating from around 1000 BC.[9]

text: Americas

text: Cotton fabrics discovered in a cave near Tehuacán, Mexico, have been dated to around 5800 BC.[10] The domestication of Gossypium hirsutum in Mexico is dated between 3400 and 2300 BC.[11]

text: In Peru, cultivation of the indigenous cotton species Gossypium barbadense has been dated, from a find in Ancon, to c 4200 BC,[12] and was the backbone of the development of coastal cultures such as the Norte Chico, Moche, and Nazca. Cotton was grown upriver, made into nets, and traded with fishing villages along the coast for large supplies of fish. The Spanish who came to Mexico and Peru in the early 16th century found the people growing cotton and wearing clothing made of it.

text: Arabia

text: The Greeks and the Arabs were not familiar with cotton until the Wars of Alexander the Great, as his contemporary Megasthenes told Seleucus I Nicator of "there being trees on which wool grows" in "Indica".[citation needed] This may be a reference to "tree cotton", Gossypium arboreum, which is a native of the Indian subcontinent.

text: According to the Columbia Encyclopedia:[9]

text: Cotton has been spun, woven, and dyed since prehistoric times. It clothed the people of ancient India, Egypt, and China. Hundreds of years before the Christian era, cotton textiles were woven in India with matchless skill, and their use spread to the Mediterranean countries.

text: Iran

text: In Iran (Persia), the history of cotton dates back to the Achaemenid era (5th century BC); however, there are few sources about the planting of cotton in pre-Islamic Iran. The planting of cotton was common in Merv, Ray and Pars of Iran. In Persian poets' poems, especially Ferdowsi's Shahname, there are references to cotton ("panbe" in Persian). Marco Polo (13th century) refers to the major products of Persia, including cotton. John Chardin, a French traveler of the 17th century who visited Safavid Persia, spoke approvingly of the vast cotton farms of Persia.[13]

text: China

text: During the Han dynasty (207 BC - 220 AD), cotton was grown by Chinese peoples in the southern Chinese province of Yunnan.[14]

text: Middle Ages

text: Eastern world

text: Egyptians grew and spun cotton in the first seven centuries of the Christian era.[15]

text: Handheld roller cotton gins had been used in India since the 6th century, and was then introduced to other countries from there.[16] Between the 12th and 14th centuries, dual-roller gins appeared in India and China. The Indian version of the dual-roller gin was prevalent throughout the Mediterranean cotton trade by the 16th century. This mechanical device was, in some areas, driven by water power.[17]

text: The spinning wheel was invented in India, between 500 and 1000 AD.[18] The earliest clear illustrations of the spinning wheel come from the Islamic world in the eleventh century.[19]

text: Europe

text: During the late medieval period, cotton became known as an imported fiber in northern Europe, without any knowledge of how it was derived, other than that it was a plant. Because Herodotus had written in his Histories, Book III, 106, that in India trees grew in the wild producing wool, it was assumed that the plant was a tree, rather than a shrub. This aspect is retained in the name for cotton in several Germanic languages, such as German Baumwolle, which translates as "tree wool" (Baum means "tree"; Wolle means "wool"). Noting its similarities to wool, people in the region could only imagine that cotton must be produced by plant-borne sheep. John Mandeville, writing in 1350, stated as fact the now-preposterous belief: "There grew there [India] a wonderful tree which bore tiny lambs on the endes of its branches. These branches were so pliable that they bent down to allow the lambs to feed when they are hungry." (See Vegetable Lamb of Tartary.) By the end of the 16th century, cotton was cultivated throughout the warmer regions in Asia and the Americas.

text: Cotton manufacture was introduced to Europe during the Muslim conquest of the Iberian Peninsula and Sicily. The knowledge of cotton weaving was spread to northern Italy in the 12th century, when Sicily was conquered by the Normans, and consequently to the rest of Europe. The spinning wheel, introduced to Europe circa 1350, improved the speed of cotton spinning.[20] By the 15th century, Venice, Antwerp, and Haarlem were important ports for cotton trade, and the sale and transportation of cotton fabrics had become very profitable.[21]

text: Early modern period

text: Mughal India

text: Under the Mughal Empire, which ruled in the Indian subcontinent from the early 16th century to the early 18th century, Indian cotton production increased, in terms of both raw cotton and cotton textiles. The Mughals introduced agrarian reforms such as a new revenue system that was biased in favour of higher value cash crops such as cotton and indigo, providing state incentives to grow cash crops, in addition to rising market demand.[22]

text: The largest manufacturing industry in the Mughal Empire was cotton textile manufacturing, which included the production of piece goods, calicos, and muslins, available unbleached and in a variety of colours. The cotton textile industry was responsible for a large part of the empire's international trade.[23] India had a 25% share of the global textile trade in the early 18th century.[24] Indian cotton textiles were the most important manufactured goods in world trade in the 18th century, consumed across the world from the Americas to Japan.[25] The most important center of cotton production was the Bengal Subah province, particularly around its capital city of Dhaka.[26]

text: The worm gear roller cotton gin, which was invented in India during the early Delhi Sultanate era of the 13th–14th centuries, came into use in the Mughal Empire some time around the 16th century,[27] and is still used in India through to the present day.[16] Another innovation, the incorporation of the crank handle in the cotton gin, first appeared in India some time during the late Delhi Sultanate or the early Mughal Empire.[28] The production of cotton, which may have largely been spun in the villages and then taken to towns in the form of yarn to be woven into cloth textiles, was advanced by the diffusion of the spinning wheel across India shortly before the Mughal era, lowering the costs of yarn and helping to increase demand for cotton. The diffusion of the spinning wheel, and the incorporation of the worm gear and crank handle into the roller cotton gin, led to greatly expanded Indian cotton textile production during the Mughal era.[29]

text: It was reported that, with an Indian cotton gin, which is half machine and half tool, one man and one woman could clean 28 pounds of cotton per day. With a modified Forbes version, one man and a boy could produce 250 pounds per day. If oxen were used to power 16 of these machines, and a few people's labour was used to feed them, they could produce as much work as 750 people did formerly.[30]

text: Egypt

text: In the early 19th century, a Frenchman named M. Jumel propositioned the then ruler of Egypt, Mohamed Ali Pasha, that he could earn a substantial income by growing an extra-long staple Maho (Gossypium barbadense) cotton, in Lower Egypt, for the French market. Mohamed Ali Pasha accepted the proposition and granted himself the monopoly on the sale and export of cotton in Egypt; and later dictated cotton should be grown in preference to other crops.

text: Egypt under Muhammad Ali in the early 19th century had the fifth most productive cotton industry in the world, in terms of the number of spindles per capita.[31] The industry was initially driven by machinery that relied on traditional energy sources, such as animal power, water wheels, and windmills, which were also the principle energy sources in Western Europe up until around 1870.[32] It was under Muhammad Ali in the early 19th century that steam engines were introduced to the Egyptian cotton industry.[32]

text: By the time of the American Civil war annual exports had reached $16 million (120,000 bales), which rose to $56 million by 1864, primarily due to the loss of the Confederate supply on the world market. Exports continued to grow even after the reintroduction of US cotton, produced now by a paid workforce, and Egyptian exports reached 1.2 million bales a year by 1903.

text: Britain

text: East India Company

text: The English East India Company introduced the Britain to cheap calico and chintz cloth on the restoration of the monarchy in the 1660s. Initially imported as a novelty side line, from its spice trading posts in Asia, the cheap colourful cloth proved popular and overtook the EIC's spice trade by value in the late 17th century. The EIC embraced the demand, particularly for calico, by expanding its factories in Asia and producing and importing cloth in bulk, creating competition for domestic woollen and linen textile producers. The impacted weavers, spinners, dyers, shepherds and farmers objected and the calico question became one of the major issues of National politics between the 1680s and the 1730s. Parliament began to see a decline in domestic textile sales, and an increase in imported textiles from places like China and India. Seeing the East India Company and their textile importation as a threat to domestic textile businesses, Parliament passed the 1700 Calico Act, blocking the importation of cotton cloth. As there was no punishment for continuing to sell cotton cloth, smuggling of the popular material became commonplace. In 1721, dissatisfied with the results of the first act, Parliament passed a stricter addition, this time prohibiting the sale of most cottons, imported and domestic (exempting only thread Fustian and raw cotton). The exemption of raw cotton from the prohibition initially saw 2 thousand bales of cotton imported annually, to become the basis of a new indigenous industry, initially producing Fustian for the domestic market, though more importantly triggering the development of a series of mechanised spinning and weaving technologies, to process the material. This mechanised production was concentrated in new cotton mills, which slowly expanded till by the beginning of the 1770's seven thousand bales of cotton were imported annually, and pressure was put on Parliament, by the new mill owners, to remove the prohibition on the production and sale of pure cotton cloth, as they could easily compete with anything the EIC could import.

text: The acts were repealed in 1774, triggering a wave of investment in mill based cotton spinning and production, doubling the demand for raw cotton within a couple of years, and doubling it again every decade, into the 1840's[33]

text: Indian cotton textiles, particularly those from Bengal, continued to maintain a competitive advantage up until the 19th century. In order to compete with India, Britain invested in labour-saving technical progress, while implementing protectionist policies such as bans and tariffs to restrict Indian imports.[34] At the same time, the East India Company's rule in India contributed to its deindustrialization, opening up a new market for British goods,[34] while the capital amassed from Bengal after its 1757 conquest was used to invest in British industries such as textile manufacturing and greatly increase British wealth.[35][36][37] British colonization also forced open the large Indian market to British goods, which could be sold in India without tariffs or duties, compared to local Indian producers who were heavily taxed, while raw cotton was imported from India without tariffs to British factories which manufactured textiles from Indian cotton, giving Britain a monopoly over India's large market and cotton resources.[38][34][39] India served as both a significant supplier of raw goods to British manufacturers and a large captive market for British manufactured goods.[40] Britain eventually surpassed India as the world's leading cotton textile manufacturer in the 19th century.[34]

text: India's cotton-processing sector changed during EIC expansion in India in the late 18th and early 19th centuries. From focusing on supplying the British market to supplying East Asia with raw cotton. As the Artisan produced textiles were no longer competitive with those produced Industrially, and Europe preferring the cheaper slave produced, long staple American, and Egyptian cottons, for its own materials.[citation needed]

text: Industrial Revolution

text: The advent of the Industrial Revolution in Britain provided a great boost to cotton manufacture, as textiles emerged as Britain's leading export. In 1738, Lewis Paul and John Wyatt, of Birmingham, England, patented the roller spinning machine, as well as the flyer-and-bobbin system for drawing cotton to a more even thickness using two sets of rollers that traveled at different speeds. Later, the invention of the James Hargreaves' spinning jenny in 1764, Richard Arkwright's spinning frame in 1769 and Samuel Crompton's spinning mule in 1775 enabled British spinners to produce cotton yarn at much higher rates. From the late 18th century on, the British city of Manchester acquired the nickname "Cottonopolis" due to the cotton industry's omnipresence within the city, and Manchester's role as the heart of the global cotton trade.

text: Production capacity in Britain and the United States was improved by the invention of the modern cotton gin by the American Eli Whitney in 1793. Before the development of cotton gins, the cotton fibers had to be pulled from the seeds tediously by hand. By the late 1700s, a number of crude ginning machines had been developed. However, to produce a bale of cotton required over 600 hours of human labor,[41] making large-scale production uneconomical in the United States, even with the use of humans as slave labor. The gin that Whitney manufactured (the Holmes design) reduced the hours down to just a dozen or so per bale. Although Whitney patented his own design for a cotton gin, he manufactured a prior design from Henry Odgen Holmes, for which Holmes filed a patent in 1796.[41] Improving technology and increasing control of world markets allowed British traders to develop a commercial chain in which raw cotton fibers were (at first) purchased from colonial plantations, processed into cotton cloth in the mills of Lancashire, and then exported on British ships to captive colonial markets in West Africa, India, and China (via Shanghai and Hong Kong).

text: By the 1840s, India was no longer capable of supplying the vast quantities of cotton fibers needed by mechanized British factories, while shipping bulky, low-price cotton from India to Britain was time-consuming and expensive. This, coupled with the emergence of American cotton as a superior type (due to the longer, stronger fibers of the two domesticated native American species, Gossypium hirsutum and Gossypium barbadense), encouraged British traders to purchase cotton from plantations in the United States and plantations in the Caribbean. By the mid-19th century, "King Cotton" had become the backbone of the southern American economy. In the United States, cultivating and harvesting cotton became the leading occupation of slaves.

text: During the American Civil War, American cotton exports slumped due to a Union blockade on Southern ports, and also because of a strategic decision by the Confederate government to cut exports, hoping to force Britain to recognize the Confederacy or enter the war. This prompted the main purchasers of cotton, Britain and France, to turn to Egyptian cotton. British and French traders invested heavily in cotton plantations. The Egyptian government of Viceroy Isma'il took out substantial loans from European bankers and stock exchanges. After the American Civil War ended in 1865, British and French traders abandoned Egyptian cotton and returned to cheap American exports,[citation needed] sending Egypt into a deficit spiral that led to the country declaring bankruptcy in 1876, a key factor behind Egypt's occupation by the British Empire in 1882.

text: During this time, cotton cultivation in the British Empire, especially Australia and India, greatly increased to replace the lost production of the American South. Through tariffs and other restrictions, the British government discouraged the production of cotton cloth in India; rather, the raw fiber was sent to England for processing. The Indian Mahatma Gandhi described the process:

text:
English people buy Indian cotton in the field, picked by Indian labor at seven cents a day, through an optional monopoly.
This cotton is shipped on British ships, a three-week journey across the Indian Ocean, down the Red Sea, across the Mediterranean, through Gibraltar, across the Bay of Biscay and the Atlantic Ocean to London. One hundred per cent profit on this freight is regarded as small.
The cotton is turned into cloth in Lancashire. You pay shilling wages instead of Indian pennies to your workers. The English worker not only has the advantage of better wages, but the steel companies of England get the profit of building the factories and machines. Wages; profits; all these are spent in England.
The finished product is sent back to India at European shipping rates, once again on British ships. The captains, officers, sailors of these ships, whose wages must be paid, are English. The only Indians who profit are a few lascars who do the dirty work on the boats for a few cents a day.
The cloth is finally sold back to the kings and landlords of India who got the money to buy this expensive cloth out of the poor peasants of India who worked at seven cents a day.[42]

text: United States

text: In the United States, Southern cotton provided capital for the continuing development of the North. The cotton was largely produced through the labor of enslaved African Americans. It enriched both the Southern landowners and the Northern merchants. Much of the Southern cotton was trans-shipped through northern ports. In this era the slogan "Cotton is king" characterized the attitude of the South toward this monocrop.

text: Cotton remained a key crop in the Southern economy after emancipation and the end of the Civil War in 1865. Across the South, sharecropping evolved, in which landless black and white farmers worked land owned by others in return for a share of the profits. Some farmers rented the land and bore the production costs themselves. Until mechanical cotton pickers were developed, cotton farmers needed additional labor to hand-pick cotton. Picking cotton was a source of income for families across the South. Rural and small town school systems had split vacations so children could work in the fields during "cotton-picking."

text: It was not until the 1950s that reliable harvesting machinery was introduced (prior to this, cotton-harvesting machinery had been too clumsy to pick cotton without shredding the fibers).[citation needed] During the first half of the 20th century, employment in the cotton industry fell, as machines began to replace laborers and the South's rural labor force dwindled during the World Wars.

text: Cotton remains a major export of the southern United States, and a majority of the world's annual cotton crop is of the long-staple American variety.[43]

text: Cultivation

text: Successful cultivation of cotton requires a long frost-free period, plenty of sunshine, and a moderate rainfall, usually from 60 to 120 cm (24 to 47 in)[citation needed]. Soils usually need to be fairly heavy, although the level of nutrients does not need to be exceptional. In general, these conditions are met within the seasonally dry tropics and subtropics in the Northern and Southern hemispheres, but a large proportion of the cotton grown today is cultivated in areas with less rainfall that obtain the water from irrigation. Production of the crop for a given year usually starts soon after harvesting the preceding autumn. Cotton is naturally a perennial but is grown as an annual to help control pests.[44] Planting time in spring in the Northern hemisphere varies from the beginning of February to the beginning of June. The area of the United States known as the South Plains is the largest contiguous cotton-growing region in the world. While dryland (non-irrigated) cotton is successfully grown in this region, consistent yields are only produced with heavy reliance on irrigation water drawn from the Ogallala Aquifer. Since cotton is somewhat salt and drought tolerant, this makes it an attractive crop for arid and semiarid regions. As water resources get tighter around the world, economies that rely on it face difficulties and conflict, as well as potential environmental problems.[45][46][47][48][49] For example, improper cropping and irrigation practices have led to desertification in areas of Uzbekistan, where cotton is a major export. In the days of the Soviet Union, the Aral Sea was tapped for agricultural irrigation, largely of cotton, and now salination is widespread.[48][49]

text: Cotton can also be cultivated to have colors other than the yellowish off-white typical of modern commercial cotton fibers. Naturally colored cotton can come in red, green, and several shades of brown.[50]

text: Genetic modification

text: Genetically modified (GM) cotton was developed to reduce the heavy reliance on pesticides. The bacterium Bacillus thuringiensis (Bt) naturally produces a chemical harmful only to a small fraction of insects, most notably the larvae of moths and butterflies, beetles, and flies, and harmless to other forms of life.[51][52][53] The gene coding for Bt toxin has been inserted into cotton, causing cotton, called Bt cotton, to produce this natural insecticide in its tissues. In many regions, the main pests in commercial cotton are lepidopteran larvae, which are killed by the Bt protein in the transgenic cotton they eat. This eliminates the need to use large amounts of broad-spectrum insecticides to kill lepidopteran pests (some of which have developed pyrethroid resistance). This spares natural insect predators in the farm ecology and further contributes to noninsecticide pest management.

text: But Bt cotton is ineffective against many cotton pests, however, such as plant bugs, stink bugs, and aphids; depending on circumstances it may still be desirable to use insecticides against these. A 2006 study done by Cornell researchers, the Center for Chinese Agricultural Policy and the Chinese Academy of Science on Bt cotton farming in China found that after seven years these secondary pests that were normally controlled by pesticide had increased, necessitating the use of pesticides at similar levels to non-Bt cotton and causing less profit for farmers because of the extra expense of GM seeds.[54] However, a 2009 study by the Chinese Academy of Sciences, Stanford University and Rutgers University refuted this.[55] They concluded that the GM cotton effectively controlled bollworm. The secondary pests were mostly miridae (plant bugs) whose increase was related to local temperature and rainfall and only continued to increase in half the villages studied. Moreover, the increase in insecticide use for the control of these secondary insects was far smaller than the reduction in total insecticide use due to Bt cotton adoption. A 2012 Chinese study concluded that Bt cotton halved the use of pesticides and doubled the level of ladybirds, lacewings and spiders.[56][57] The International Service for the Acquisition of Agri-biotech Applications (ISAAA) said that, worldwide, GM cotton was planted on an area of 25 million hectares in 2011.[58] This was 69% of the worldwide total area planted in cotton.

text: GM cotton acreage in India grew at a rapid rate, increasing from 50,000 hectares in 2002 to 10.6 million hectares in 2011. The total cotton area in India was 12.1 million hectares in 2011, so GM cotton was grown on 88% of the cotton area. This made India the country with the largest area of GM cotton in the world.[58] A long-term study on the economic impacts of Bt cotton in India, published in the Journal PNAS in 2012, showed that Bt cotton has increased yields, profits, and living standards of smallholder farmers.[59] The U.S. GM cotton crop was 4.0 million hectares in 2011 the second largest area in the world, the Chinese GM cotton crop was third largest by area with 3.9 million hectares and Pakistan had the fourth largest GM cotton crop area of 2.6 million hectares in 2011.[58] The initial introduction of GM cotton proved to be a success in Australia – the yields were equivalent to the non-transgenic varieties and the crop used much less pesticide to produce (85% reduction).[60] The subsequent introduction of a second variety of GM cotton led to increases in GM cotton production until 95% of the Australian cotton crop was GM in 2009[61] making Australia the country with the fifth largest GM cotton crop in the world.[58] Other GM cotton growing countries in 2011 were Argentina, Myanmar, Burkina Faso, Brazil, Mexico, Colombia, South Africa and Costa Rica.[58]

text: Cotton has been genetically modified for resistance to glyphosate a broad-spectrum herbicide discovered by Monsanto which also sells some of the Bt cotton seeds to farmers. There are also a number of other cotton seed companies selling GM cotton around the world. About 62% of the GM cotton grown from 1996 to 2011 was insect resistant, 24% stacked product and 14% herbicide resistant.[58]

text: Cotton has gossypol, a toxin that makes it inedible. However, scientists have silenced the gene that produces the toxin, making it a potential food crop.[62]

text: Organic production

text: Organic cotton is generally understood as cotton from plants not genetically modified and that is certified to be grown without the use of any synthetic agricultural chemicals, such as fertilizers or pesticides.[63] Its production also promotes and enhances biodiversity and biological cycles.[64] In the United States, organic cotton plantations are required to enforce the National Organic Program (NOP). This institution determines the allowed practices for pest control, growing, fertilizing, and handling of organic crops.[65][66] As of 2007, 265,517 bales of organic cotton were produced in 24 countries, and worldwide production was growing at a rate of more than 50% per year.[67]

text: Pests and weeds

text: The cotton industry relies heavily on chemicals, such as herbicides, fertilizers and insecticides, although a very small number of farmers are moving toward an organic model of production, and organic cotton products are now available for purchase at limited locations. These are popular for baby clothes and diapers. Under most definitions, organic products do not use genetic engineering. All natural cotton products are known to be both sustainable and hypoallergenic.

text: Historically, in North America, one of the most economically destructive pests in cotton production has been the boll weevil. Due to the US Department of Agriculture's highly successful Boll Weevil Eradication Program (BWEP), this pest has been eliminated from cotton in most of the United States. This program, along with the introduction of genetically engineered Bt cotton (which contains a bacterial gene that codes for a plant-produced protein that is toxic to a number of pests such as cotton bollworm and pink bollworm), has allowed a reduction in the use of synthetic insecticides.

text: Other significant global pests of cotton include the pink bollworm, Pectinophora gossypiella; the chili thrips, Scirtothrips dorsalis; the cotton seed bug, Oxycarenus hyalinipennis; the tarnish plant bug, Lygus lineolaris; and the fall armyworm, Spodoptera frugiperda, Xanthomonas citri subsp. malvacearum.

text: Harvesting

text: Most cotton in the United States, Europe and Australia is harvested mechanically, either by a cotton picker, a machine that removes the cotton from the boll without damaging the cotton plant, or by a cotton stripper, which strips the entire boll off the plant. Cotton strippers are used in regions where it is too windy to grow picker varieties of cotton, and usually after application of a chemical defoliant or the natural defoliation that occurs after a freeze. Cotton is a perennial crop in the tropics, and without defoliation or freezing, the plant will continue to grow.

text: Cotton continues to be picked by hand in developing countries.[68]

text: Competition from synthetic fibers

text: The era of manufactured fibers began with the development of rayon in France in the 1890s. Rayon is derived from a natural cellulose and cannot be considered synthetic, but requires extensive processing in a manufacturing process, and led the less expensive replacement of more naturally derived materials. A succession of new synthetic fibers were introduced by the chemicals industry in the following decades. Acetate in fiber form was developed in 1924. Nylon, the first fiber synthesized entirely from petrochemicals, was introduced as a sewing thread by DuPont in 1936, followed by DuPont's acrylic in 1944. Some garments were created from fabrics based on these fibers, such as women's hosiery from nylon, but it was not until the introduction of polyester into the fiber marketplace in the early 1950s that the market for cotton came under threat.[69] The rapid uptake of polyester garments in the 1960s caused economic hardship in cotton-exporting economies, especially in Central American countries, such as Nicaragua, where cotton production had boomed tenfold between 1950 and 1965 with the advent of cheap chemical pesticides. Cotton production recovered in the 1970s, but crashed to pre-1960 levels in the early 1990s.[70]

text: Uses

text: Cotton is used to make a number of textile products. These include terrycloth for highly absorbent bath towels and robes; denim for blue jeans; cambric, popularly used in the manufacture of blue work shirts (from which we get the term "blue-collar"); and corduroy, seersucker, and cotton twill. Socks, underwear, and most T-shirts are made from cotton. Bed sheets often are made from cotton. Cotton also is used to make yarn used in crochet and knitting. Fabric also can be made from recycled or recovered cotton that otherwise would be thrown away during the spinning, weaving, or cutting process. While many fabrics are made completely of cotton, some materials blend cotton with other fibers, including rayon and synthetic fibers such as polyester. It can either be used in knitted or woven fabrics, as it can be blended with elastine to make a stretchier thread for knitted fabrics, and apparel such as stretch jeans. Cotton can be blended also with linen as Linen-cotton blends which give benefit of both plant materials which wrinkle resistant, lightweight, breathable and can keep heat more effectively than only linen. These blends are thinner and lighter, but stronger than only cotton.[71]

text: In addition to the textile industry, cotton is used in fishing nets, coffee filters, tents, explosives manufacture (see nitrocellulose), cotton paper, and in bookbinding. The first Chinese paper was made of cotton fiber.[citation needed] Fire hoses were once made of cotton.

text: The cottonseed which remains after the cotton is ginned is used to produce cottonseed oil, which, after refining, can be consumed by humans like any other vegetable oil. The cottonseed meal that is left generally is fed to ruminant livestock; the gossypol remaining in the meal is toxic to monogastric animals. Cottonseed hulls can be added to dairy cattle rations for roughage. During the American slavery period, cotton root bark was used in folk remedies as an abortifacient, that is, to induce a miscarriage. Gossypol was one of the many substances found in all parts of the cotton plant and it was described by the scientists as 'poisonous pigment'. It also appears to inhibit the development of sperm or even restrict the mobility of the sperm. Also, it is thought to interfere with the menstrual cycle by restricting the release of certain hormones.[72]

text: Cotton linters are fine, silky fibers which adhere to the seeds of the cotton plant after ginning. These curly fibers typically are less than 1⁄8 inch (3.2 mm) long. The term also may apply to the longer textile fiber staple lint as well as the shorter fuzzy fibers from some upland species. Linters are traditionally used in the manufacture of paper and as a raw material in the manufacture of cellulose. In the UK, linters are referred to as "cotton wool". This can also be a refined product (absorbent cotton in U.S. usage) which has medical, cosmetic and many other practical uses. The first medical use of cotton wool was by Sampson Gamgee at the Queen's Hospital (later the General Hospital) in Birmingham, England.

text: Shiny cotton is a processed version of the fiber that can be made into cloth resembling satin for shirts and suits. However, it is hydrophobic (does not absorb water easily), which makes it unfit for use in bath and dish towels (although examples of these made from shiny cotton are seen).

text: The name Egyptian cotton is broadly associated with quality products, however only a small percentage of "Egyptian cotton" products are actually of superior quality. Most products bearing the name are not made with cotton from Egypt.[73]

text: Pima cotton is often compared to Egyptian cotton, as both are used in high quality bed sheets and other cotton products. It is considered the next best quality after high quality Egyptian cotton by some authorities. Pima cotton is grown in the American southwest. Not all products bearing the Pima name are made with the finest cotton. The Pima name is now used by cotton-producing nations such as Peru, Australia and Israel.[74]

text: Cotton lisle is a finely-spun, tightly twisted type of cotton that is noted for being strong and durable. Lisle is composed of two strands that have each been twisted an extra twist per inch than ordinary yarns and combined to create a single thread. The yarn is spun so that it is compact and solid. This cotton is used mainly for underwear, stockings, and gloves. Colors applied to this yarn are noted for being more brilliant than colors applied to softer yarn. This type of thread was first made in the city of Lisle, France (now Lille), hence its name.[75][76][77]

text: International trade

text: The largest producers of cotton, currently (2009), are China and India, with annual production of about 34 million bales and 33.4 million bales, respectively; most of this production is consumed by their respective textile industries. The largest exporters of raw cotton are the United States, with sales of $4.9 billion, and Africa, with sales of $2.1 billion. The total international trade is estimated to be $12 billion. Africa's share of the cotton trade has doubled since 1980. Neither area has a significant domestic textile industry, textile manufacturing having moved to developing nations in Eastern and South Asia such as India and China. In Africa, cotton is grown by numerous small holders. Dunavant Enterprises, based in Memphis, Tennessee, is the leading cotton broker in Africa, with hundreds of purchasing agents. It operates cotton gins in Uganda, Mozambique, and Zambia. In Zambia, it often offers loans for seed and expenses to the 180,000 small farmers who grow cotton for it, as well as advice on farming methods. Cargill also purchases cotton in Africa for export.

text: The 25,000 cotton growers in the United States are heavily subsidized at the rate of $2 billion per year although China now provides the highest overall level of cotton sector support.[78] The future of these subsidies is uncertain and has led to anticipatory expansion of cotton brokers' operations in Africa. Dunavant expanded in Africa by buying out local operations. This is only possible in former British colonies and Mozambique; former French colonies continue to maintain tight monopolies, inherited from their former colonialist masters, on cotton purchases at low fixed prices.[79]

text: Leading producer countries

text:
Top 10 Cotton Producing Countries (in metric tonnes)

Rank
Country
2010
2012
2014

1
 China
5,970,000
6,281,000
6,532,000

2
 India
5,683,000
6,071,000
6,423,000

3
 United States
3,941,700
3,412,550
3,553,000

4
 Pakistan
1,869,000
2,312,000
2,308,000

5
 Brazil
973,449
1,673,337
1,524,103

6
 Uzbekistan
1,136,120
983,400
849,000

7
 Turkey
816,705
754,600
697,000

8
 Australia
386,800
473,497
501,000

9
 Turkmenistan
230,000
295,000
210,000

10
 Mexico
225,000
195,000
198,000

Source: UN Food & Agriculture Organization[80]

text: The five leading exporters of cotton in 2011 are (1) the United States, (2) India, (3) Brazil, (4) Australia, and (5) Uzbekistan. The largest nonproducing importers are Korea, Taiwan, Russia, and Japan.[81]

text: In India, the states of Maharashtra (26.63%), Gujarat (17.96%) and Andhra Pradesh (13.75%) and also Madhya Pradesh are the leading cotton producing states,[82] these states have a predominantly tropical wet and dry climate.

text: In the United States, the state of Texas led in total production as of 2004,[83] while the state of California had the highest yield per acre.[84]

text: Fair trade

text: Cotton is an enormously important commodity throughout the world. However, many farmers in developing countries receive a low price for their produce, or find it difficult to compete with developed countries.

text: This has led to an international dispute (see United States – Brazil cotton dispute):

text: On 27 September 2002, Brazil requested consultations with the US regarding prohibited and actionable subsidies provided to US producers, users and/or exporters of upland cotton, as well as legislation, regulations, statutory instruments and amendments thereto providing such subsidies (including export credits), grants, and any other assistance to the US producers, users and exporters of upland cotton.[85]

text: On 8 September 2004, the Panel Report recommended that the United States "withdraw" export credit guarantees and payments to domestic users and exporters, and "take appropriate steps to remove the adverse effects or withdraw" the mandatory price-contingent subsidy measures.[86]

text: While Brazil was fighting the US through the WTO's Dispute Settlement Mechanism against a heavily subsidized cotton industry, a group of four least-developed African countries – Benin, Burkina Faso, Chad, and Mali – also known as "Cotton-4" have been the leading protagonist for the reduction of US cotton subsidies through negotiations. The four introduced a "Sectoral Initiative in Favour of Cotton", presented by Burkina Faso's President Blaise Compaoré during the Trade Negotiations Committee on 10 June 2003.[87]

text: In addition to concerns over subsidies, the cotton industries of some countries are criticized for employing child labor and damaging workers' health by exposure to pesticides used in production. The Environmental Justice Foundation has campaigned against the prevalent use of forced child and adult labor in cotton production in Uzbekistan, the world's third largest cotton exporter.[88] The international production and trade situation has led to "fair trade" cotton clothing and footwear, joining a rapidly growing market for organic clothing, fair fashion or "ethical fashion". The fair trade system was initiated in 2005 with producers from Cameroon, Mali and Senegal.[89]

text: Trade

text: Cotton is bought and sold by investors and price speculators as a tradable commodity on 2 different stock exchanges in the United States of America.

text:
Cotton No. 2 futures contracts are traded on the New York Board of Trade (NYBOT) under the ticker symbol CT. They are delivered every year in March, May, July, October, and December.[90]
Cotton futures contracts are traded on the New York Mercantile Exchange (NYMEX) under the ticker symbol TT. They are delivered every year in March, May, July, October, and December.[91]

text: Critical temperatures

text:
Favorable travel temperature range: below 25 °C (77 °F)
Optimum travel temperature: 21 °C (70 °F)
Glow temperature: 205 °C (401 °F)
Fire point: 210 °C (410 °F)
Autoignition temperature: 360 °C (680 °F) - 425 °C (797 °F)[92]
Autoignition temperature (for oily cotton): 120 °C (248 °F)

text: A temperature range of 25 to 35 °C (77 to 95 °F) is the optimal range for mold development. At temperatures below 0 °C (32 °F), rotting of wet cotton stops. Damaged cotton is sometimes stored at these temperatures to prevent further deterioration.[93]

text: British standard yarn measures

text:
1 thread = 55 in or 140 cm
1 skein or rap = 80 threads (120 yd or 110 m)
1 hank = 7 skeins (840 yd or 770 m)
1 spindle = 18 hanks (15,120 yd or 13.83 km)

text: Fiber properties

text: This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (December 2012) (Learn how and when to remove this template message)

text:
Property
Evaluation

Shape
Fairly uniform in width, 12–20 micrometers;
length varies from 1 cm to 6 cm (½ to 2½ inches);
typical length is 2.2 cm to 3.3 cm (⅞ to 1¼ inches).

Luster
high

Tenacity (strength)
Dry
Wet

3.0–5.0 g/d
3.3–6.0 g/d

Resiliency
low

Density
1.54–1.56 g/cm³

Moisture absorption
raw: conditioned
saturation
mercerized: conditioned
saturation

8.5%
15–25%
8.5–10.3%
15–27%+

Dimensional stability
good

Resistance to
acids
alkali
organic solvents
sunlight
microorganisms
insects

damage, weaken fibers
resistant; no harmful effects
high resistance to most
Prolonged exposure weakens fibers.
Mildew and rot-producing bacteria damage fibers.
Silverfish damage fibers.

Thermal reactions
to heat
to flame

Decomposes after prolonged exposure to temperatures of 150 °C or over.
Burns readily.

text: The chemical composition of cotton is as follows:

text:
cellulose 91.00%
water 7.85%
protoplasm, pectins 0.55%
waxes, fatty substances 0.40%
mineral salts 0.20%

text: Cotton genome

text: This article may be too technical for most readers to understand. Please help improve it to make it understandable to non-experts, without removing the technical details. The talk page may contain suggestions. (January 2011) (Learn how and when to remove this template message)

text: A public genome sequencing effort of cotton was initiated[94] in 2007 by a consortium of public researchers. They agreed on a strategy to sequence the genome of cultivated, tetraploid cotton. "Tetraploid" means that cultivated cotton actually has two separate genomes within its nucleus, referred to as the A and D genomes. The sequencing consortium first agreed to sequence the D-genome relative of cultivated cotton (G. raimondii, a wild Central American cotton species) because of its small size and limited number of repetitive elements. It is nearly one-third the number of bases of tetraploid cotton (AD), and each chromosome is only present once.[clarification needed] The A genome of G. arboreum would be sequenced next. Its genome is roughly twice the size of G. raimondii's. Part of the difference in size between the two genomes is the amplification of retrotransposons (GORGE). Once both diploid genomes are assembled, then research could begin sequencing the actual genomes of cultivated cotton varieties. This strategy is out of necessity; if one were to sequence the tetraploid genome without model diploid genomes, the euchromatic DNA sequences of the AD genomes would co-assemble and the repetitive elements of AD genomes would assembly independently into A and D sequences respectively. Then there would be no way to untangle the mess of AD sequences without comparing them to their diploid counterparts.

text: The public sector effort continues with the goal to create a high-quality, draft genome sequence from reads generated by all sources. The public-sector effort has generated Sanger reads of BACs, fosmids, and plasmids as well as 454 reads. These later types of reads will be instrumental in assembling an initial draft of the D genome. In 2010, two companies (Monsanto and Illumina), completed enough Illumina sequencing to cover the D genome of G. raimondii about 50x.[95] They announced that they would donate their raw reads to the public. This public relations effort gave them some recognition for sequencing the cotton genome. Once the D genome is assembled from all of this raw material, it will undoubtedly assist in the assembly of the AD genomes of cultivated varieties of cotton, but a lot of hard work remains.


document_title: Sunlight

question_text: how much light does the sun give off

question_tokens: how much light does the sun give off

root

text: Sunlight

text: Measurement[edit]

text: Researchers can measure the intensity of sunlight using a sunshine recorder, pyranometer, or pyrheliometer. To calculate the amount of sunlight reaching the ground, both Earth's elliptical orbit and the attenuation by Earth's atmosphere have to be taken into account. The extraterrestrial solar illuminance (Eext), corrected for the elliptical orbit by using the day number of the year (dn), is given to a good approximation by[4]

tag: p

text: where dn=1 on January 1st; dn=32 on February 1st; dn=59 on March 1 (except on leap years, where dn=60), etc. In this formula dn–3 is used, because in modern times Earth's perihelion, the closest approach to the Sun and, therefore, the maximum Eext occurs around January 3 each year. The value of 0.033412 is determined knowing that the ratio between the perihelion (0.98328989 AU) squared and the aphelion (1.01671033 AU) squared should be approximately 0.935338.

text: The solar illuminance constant (Esc), is equal to 128×103 lx. The direct normal illuminance (Edn), corrected for the attenuating effects of the atmosphere is given by:

text: where c is the atmospheric extinction and m is the relative optical airmass. The atmospheric extinction brings the number of lux down to around 100 000.

text: The total amount of energy received at ground level from the Sun at the zenith depends on the distance to the Sun and thus on the time of year. It is about 3.3% higher than average in January and 3.3% lower in July (see below). If the extraterrestrial solar radiation is 1367 watts per square meter (the value when the Earth–Sun distance is 1 astronomical unit), then the direct sunlight at Earth's surface when the Sun is at the zenith is about 1050 W/m2, but the total amount (direct and indirect from the atmosphere) hitting the ground is around 1120 W/m2.[5] In terms of energy, sunlight at Earth's surface is around 52 to 55 percent infrared (above 700 nm), 42 to 43 percent visible (400 to 700 nm), and 3 to 5 percent ultraviolet (below 400 nm).[6] At the top of the atmosphere, sunlight is about 30% more intense, having about 8% ultraviolet (UV),[7] with most of the extra UV consisting of biologically damaging short-wave ultraviolet.[8]

text: Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux. This is higher than the efficacy (of source) of most artificial lighting (including fluorescent), which means using sunlight for illumination heats up a room less than using most forms of artificial lighting.

text: Multiplying the figure of 1050 watts per square metre by 93 lumens per watt indicates that bright sunlight provides an illuminance of approximately 98 000 lux (lumens per square meter) on a perpendicular surface at sea level. The illumination of a horizontal surface will be considerably less than this if the Sun is not very high in the sky. Averaged over a day, the highest amount of sunlight on a horizontal surface occurs in January at the South Pole (see insolation).

text: Dividing the irradiance of 1050 W/m2 by the size of the sun's disk in steradians gives an average radiance of 15.4 MW per square metre per steradian. (However, the radiance at the centre of the sun's disk is somewhat higher than the average over the whole disk due to limb darkening.) Multiplying this by π gives an upper limit to the irradiance which can be focused on a surface using mirrors: 48.5 MW/m2.

text: Composition and power[edit]

text: The spectrum of the Sun's solar radiation is close to that of a black body[9][10] with a temperature of about 5,800 K.[11] The Sun emits EM radiation across most of the electromagnetic spectrum. Although the Sun produces gamma rays as a result of the nuclear-fusion process, internal absorption and thermalization convert these super-high-energy photons to lower-energy photons before they reach the Sun's surface and are emitted out into space. As a result, the Sun does not emit gamma rays from this process, but it does emit gamma rays from solar flares.[12] The Sun also emits X-rays, ultraviolet, visible light, infrared, and even radio waves;[13] the only direct signature of the nuclear process is the emission of neutrinos.

text: Although the solar corona is a source of extreme ultraviolet and X-ray radiation, these rays make up only a very small amount of the power output of the Sun (see spectrum at right). The spectrum of nearly all solar electromagnetic radiation striking the Earth's atmosphere spans a range of 100 nm to about 1 mm (1,000,000 nm).[citation needed] This band of significant radiation power can be divided into five regions in increasing order of wavelengths:[14]

text:
Ultraviolet C or (UVC) range, which spans a range of 100 to 280 nm. The term ultraviolet refers to the fact that the radiation is at higher frequency than violet light (and, hence, also invisible to the human eye). Due to absorption by the atmosphere very little reaches Earth's surface. This spectrum of radiation has germicidal properties, as used in germicidal lamps.
Ultraviolet B or (UVB) range spans 280 to 315 nm. It is also greatly absorbed by the Earth's atmosphere, and along with UVC causes the photochemical reaction leading to the production of the ozone layer. It directly damages DNA and causes sunburn, but is also required for vitamin D synthesis in the skin and fur of mammals.[15]
Ultraviolet A or (UVA) spans 315 to 400 nm. This band was once[when?] held to be less damaging to DNA, and hence is used in cosmetic artificial sun tanning (tanning booths and tanning beds) and PUVA therapy for psoriasis. However, UVA is now known to cause significant damage to DNA via indirect routes (formation of free radicals and reactive oxygen species), and can cause cancer.[16]
Visible range or light spans 380 to 780 nm. As the name suggests, this range is visible to the naked eye. It is also the strongest output range of the Sun's total irradiance spectrum.
Infrared range that spans 700 nm to 1,000,000 nm (1 mm). It comprises an important part of the electromagnetic radiation that reaches Earth. Scientists divide the infrared range into three types on the basis of wavelength:

Infrared-A: 700 nm to 1,400 nm
Infrared-B: 1,400 nm to 3,000 nm
Infrared-C: 3,000 nm to 1 mm.

tag: ul

text: Published tables[edit]

text: Tables of direct solar radiation on various slopes from 0 to 60 degrees north latitude, in calories per square centimetre, issued in 1972 and published by Pacific Northwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture, Portland, Oregon, USA, appear on the web.[17]

text: Solar constant[edit]

text: The solar constant, a measure of flux density, is the amount of incoming solar electromagnetic radiation per unit area that would be incident on a plane perpendicular to the rays, at a distance of one astronomical unit (AU) (roughly the mean distance from the Sun to Earth). The "solar constant" includes all types of solar radiation, not just the visible light. Its average value was thought to be approximately 1366 W/m²,[18] varying slightly with solar activity, but recent recalibrations of the relevant satellite observations indicate a value closer to 1361 W/m² is more realistic.[19]

text: Total solar irradiance (TSI) and spectral solar irradiance (SSI) upon Earth[edit]

text: Total solar irradiance (TSI) – the amount of solar radiation received at the top of Earth's atmosphere – has been measured since 1978 by a series of overlapping NASA and ESA satellite experiments to be 1.361 kilowatts per square meter (kW/m²).[18][20][21][22] TSI observations are continuing today with the ACRIMSAT/ACRIM3, SOHO/VIRGO and SORCE/TIM satellite experiments.[23] Variation of TSI has been discovered on many timescales including the solar magnetic cycle [24] and many shorter periodic cycles.[25] TSI provides the energy that drives Earth's climate, so continuation of the TSI time series database is critical to understanding the role of solar variability in climate change.

text: Spectral solar irradiance (SSI) – the spectral distribution of the TSI – has been monitored since 2003 by the SORCE Spectral Irradiance Monitor (SIM). It has been found that SSI at UV (ultraviolet) wavelength corresponds in a less clear, and probably more complicated fashion, with Earth's climate responses than earlier assumed, fueling broad avenues of new research in “the connection of the Sun and stratosphere, troposphere, biosphere, ocean, and Earth’s climate”.[26]

text: Intensity in the Solar System[edit]

text: Different bodies of the Solar System receive light of an intensity inversely proportional to the square of their distance from Sun. A rough table comparing the amount of solar radiation received by each planet in the Solar System follows (from data in [1]):

text:
Planet or dwarf planet
distance (AU)
Solar radiation (W/m²)

Perihelion
Aphelion
maximum
minimum

Mercury
0.3075
0.4667
14,446
6,272

Venus
0.7184
0.7282
2,647
2,576

Earth
0.9833
1.017
1,413
1,321

Mars
1.382
1.666
715
492

Jupiter
4.950
5.458
55.8
45.9

Saturn
9.048
10.12
16.7
13.4

Uranus
18.38
20.08
4.04
3.39

Neptune
29.77
30.44
1.54
1.47

Pluto
29.66
48.87
1.55
0.57

tag: table

text: The actual brightness of sunlight that would be observed at the surface depends also on the presence and composition of an atmosphere. For example, Venus's thick atmosphere reflects more than 60% of the solar light it receives. The actual illumination of the surface is about 14,000 lux, comparable to that on Earth "in the daytime with overcast clouds".[27]

text: Sunlight on Mars would be more or less like daylight on Earth during a slightly overcast day, and, as can be seen in the pictures taken by the rovers, there is enough diffuse sky radiation that shadows would not seem particularly dark. Thus, it would give perceptions and "feel" very much like Earth daylight. The spectrum on the surface is slightly redder than that on Earth, due to scattering by reddish dust in the Martian atmosphere.

text: For comparison, sunlight on Saturn is slightly brighter than Earth sunlight at the average sunset or sunrise (see daylight for comparison table). Even on Pluto, the sunlight would still be bright enough to almost match the average living room. To see sunlight as dim as full moonlight on Earth, a distance of about 500 AU (~69 light-hours) is needed; there are only a handful of objects in the Solar System known to orbit farther than such a distance, among them 90377 Sedna and (87269) 2000 OO67.

text: Surface illumination[edit]

text: The spectrum of surface illumination depends upon solar elevation due to atmospheric effects, with the blue spectral component dominating during twilight before and after sunrise and sunset, respectively, and red dominating during sunrise and sunset. These effects are apparent in natural light photography where the principal source of illumination is sunlight as mediated by the atmosphere.

text: While the color of the sky is usually determined by Rayleigh scattering, an exception occurs at sunset and twilight. "Preferential absorption of sunlight by ozone over long horizon paths gives the zenith sky its blueness when the sun is near the horizon".[28]

text: See diffuse sky radiation for more details.

text: Spectral composition of sunlight at Earth's surface[edit]

text: The Sun's electromagnetic radiation which is received at the Earth's surface is predominantly light that falls within the range of wavelengths to which the visual systems of the animals that inhabit Earth's surface are sensitive. The Sun may therefore be said to illuminate, which is a measure of the light within a specific sensitivity range. Many animals (including humans) have a sensitivity range of approximately 400–700 nm,[29] and given optimal conditions the absorption and scattering by Earth's atmosphere produces illumination that approximates an equal-energy illuminant for most of this range.[30] The useful range for color vision in humans, for example, is approximately 450–650 nm. Aside from effects that arise at sunset and sunrise, the spectral composition changes primarily in respect to how directly sunlight is able to illuminate. When illumination is indirect, Rayleigh scattering in the upper atmosphere will lead blue wavelengths to dominate. Water vapour in the lower atmosphere produces further scattering and ozone, dust and water particles will also absorb selective wavelengths.[31][32]

text: Variations in solar irradiance[edit]

text: Seasonal and orbital variation[edit]

text: On Earth, the solar radiation varies with the angle of the sun above the horizon, with longer sunlight duration at high latitudes during summer, varying to no sunlight at all in winter near the pertinent pole. When the direct radiation is not blocked by clouds, it is experienced as sunshine. The warming of the ground (and other objects) depends on the absorption of the electromagnetic radiation in the form of heat.

text: The amount of radiation intercepted by a planetary body varies inversely with the square of the distance between the star and the planet. Earth's orbit and obliquity change with time (over thousands of years), sometimes forming a nearly perfect circle, and at other times stretching out to an orbital eccentricity of 5% (currently 1.67%). As the orbital eccentricity changes, the average distance from the sun (the semimajor axis does not significantly vary, and so the total insolation over a year remains almost constant due to Kepler's second law,

text:
where

A

{\displaystyle A}

 is the "areal velocity" invariant. That is, the integration over the orbital period (also invariant) is a constant.

text: If we assume the solar radiation power P as a constant over time and the solar irradiation given by the inverse-square law, we obtain also the average insolation as a constant.

text: But the seasonal and latitudinal distribution and intensity of solar radiation received at Earth's surface does vary.[33] The effect of sun angle on climate results in the change in solar energy in summer and winter. For example, at latitudes of 65 degrees, this can vary by more than 25% as a result of Earth's orbital variation. Because changes in winter and summer tend to offset, the change in the annual average insolation at any given location is near zero, but the redistribution of energy between summer and winter does strongly affect the intensity of seasonal cycles. Such changes associated with the redistribution of solar energy are considered a likely cause for the coming and going of recent ice ages (see: Milankovitch cycles).

text: Solar intensity variation[edit]

text: Space-based observations of solar irradiance started in 1978. These measurements show that the solar constant is not constant. It varies on many time scales, including the 11-year sunspot solar cycle.[24] When going further back in time, one has to rely on irradiance reconstructions, using sunspots for the past 400 years or cosmogenic radionuclides for going back 10,000 years. Such reconstructions have been done.[34][35][36][37] These studies show that in addition to the solar irradiance variation with the solar cycle (the (Schwabe) cycle), the solar activitiy varies with longer cycles, such as the proposed 88 year (Gleisberg cycle), 208 year (DeVries cycle) and 1,000 year (Eddy cycle).

text: Life on Earth[edit]

text: The existence of nearly all life on Earth is fueled by light from the Sun. Most autotrophs, such as plants, use the energy of sunlight, combined with carbon dioxide and water, to produce simple sugars—a process known as photosynthesis. These sugars are then used as building-blocks and in other synthetic pathways that allow the organism to grow.

text: Heterotrophs, such as animals, use light from the Sun indirectly by consuming the products of autotrophs, either by consuming autotrophs, by consuming their products, or by consuming other heterotrophs. The sugars and other molecular components produced by the autotrophs are then broken down, releasing stored solar energy, and giving the heterotroph the energy required for survival. This process is known as cellular respiration.

text: In prehistory, humans began to further extend this process by putting plant and animal materials to other uses. They used animal skins for warmth, for example, or wooden weapons to hunt. These skills allowed humans to harvest more of the sunlight than was possible through glycolysis alone, and human population began to grow.

text: During the Neolithic Revolution, the domestication of plants and animals further increased human access to solar energy. Fields devoted to crops were enriched by inedible plant matter, providing sugars and nutrients for future harvests. Animals that had previously provided humans with only meat and tools once they were killed were now used for labour throughout their lives, fueled by grasses inedible to humans.

text: The more recent discoveries of coal, petroleum and natural gas are modern extensions of this trend. These fossil fuels are the remnants of ancient plant and animal matter, formed using energy from sunlight and then trapped within Earth for millions of years. Because the stored energy in these fossil fuels has accumulated over many millions of years, they have allowed modern humans to massively increase the production and consumption of primary energy. As the amount of fossil fuel is large but finite, this cannot continue indefinitely, and various theories exist as to what will follow this stage of human civilization (e.g., alternative fuels, Malthusian catastrophe, new urbanism, peak oil).

text: Cultural aspects[edit]

text: This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (February 2011) (Learn how and when to remove this template message)

text: The effect of sunlight is relevant to painting, evidenced for instance in works of Claude Monet on outdoor scenes and landscapes.

text: Many people find direct sunlight to be too bright for comfort, especially when reading from white paper upon which the sun is directly shining. Indeed, looking directly at the sun can cause long-term vision damage. To compensate for the brightness of sunlight, many people wear sunglasses. Cars, many helmets and caps are equipped with visors to block the sun from direct vision when the sun is at a low angle. Sunshine is often blocked from entering buildings through the use of walls, window blinds, awnings, shutters, curtains, or nearby shade trees.

text: In colder countries, many people prefer sunnier days and often avoid the shade. In hotter countries, the converse is true; during the midday hours, many people prefer to stay inside to remain cool. If they do go outside, they seek shade that may be provided by trees, parasols, and so on.

text: In Hinduism, the sun is considered to be a god, as it is the source of life and energy on earth.

text: Sunbathing[edit]

text: This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (January 2015) (Learn how and when to remove this template message)

text: Sunbathing is a popular leisure activity in which a person sits or lies in direct sunshine. People often sunbathe in comfortable places where there is ample sunlight. Some common places for sunbathing include beaches, open air swimming pools, parks, gardens, and sidewalk cafes. Sunbathers typically wear limited amounts of clothing or some simply go nude. For some, an alternative to sunbathing is the use of a sunbed that generates ultraviolet light and can be used indoors regardless of weather conditions. Tanning beds have been banned in a number of states in the world.

text: For many people with light skin, one purpose for sunbathing is to darken one's skin color (get a sun tan), as this is considered in some cultures to be attractive, associated with outdoor activity, vacations/holidays, and health. Some people prefer naked sunbathing so that an "all-over" or "even" tan can be obtained, sometimes as part of a specific lifestyle.

text: For people suffering from psoriasis, sunbathing is an effective way of healing the symptoms.

text: Skin tanning is achieved by an increase in the dark pigment inside skin cells called melanocytes, and is an automatic response mechanism of the body to sufficient exposure to ultraviolet radiation from the sun or from artificial sunlamps. Thus, the tan gradually disappears with time, when one is no longer exposed to these sources.

text: Effects on human health[edit]

text: The ultraviolet radiation in sunlight has both positive and negative health effects, as it is both a principal source of vitamin D3 and a mutagen.[38] A dietary supplement can supply vitamin D without this mutagenic effect,[39] but bypasses natural mechanisms that would prevent overdoses of vitamin D generated internally from sunlight. Vitamin D has a wide range of positive health effects, which include strengthening bones[40] and possibly inhibiting the growth of some cancers.[41][42] Sun exposure has also been associated with the timing of melatonin synthesis, maintenance of normal circadian rhythms, and reduced risk of seasonal affective disorder.[43]

text: Long-term sunlight exposure is known to be associated with the development of skin cancer, skin aging, immune suppression, and eye diseases such as cataracts and macular degeneration.[44] Short-term overexposure is the cause of sunburn, snow blindness, and solar retinopathy.

text: UV rays, and therefore sunlight and sunlamps, are the only listed carcinogens that are known to have health benefits,[45] and a number of public health organizations state that there needs to be a balance between the risks of having too much sunlight or too little.[46] There is a general consensus that sunburn should always be avoided.

text: Epidemiological data shows that people who have more exposure to the sun have less high blood pressure and cardiovascular-related mortality. While sunlight (and its UV rays) are a risk factor for skin cancer, "sun avoidance may carry more of a cost than benefit for over-all good health."[47] A study found that there is no evidence that UV reduces lifespan in contrast to other risk factors like smoking, alcohol and high blood pressure.[47]

text: Effect on plant genomes[edit]

text: Elevated solar UV-B doses increase the frequency of DNA recombination in Arabidopsis thaliana and tobacco (Nicotiana tabacum) plants.[48] These increases are accompanied by strong induction of an enzyme with a key role in recombinational repair of DNA damage. Thus the level of terrestrial solar UV-B radiation likely affects genome stability in plants.


document_title: Tax-Free Savings Account

question_text: when did the tax free savings account start

text: Tax-Free Savings Account

text: History[edit]

text: The first Tax-Free Savings Account was introduced by Jim Flaherty, then Canadian federal Minister of Finance, in the 2008 federal budget. It came into effect on January 1, 2009.[2]

text: This measure was supported by the C.D. Howe Institute, which stated; “This tax policy gem is very good news for Canadians, and Mr. Flaherty and his government deserve credit for a novel program”.[3] Furthermore, the Canadian Federation of Independent Business,[4] Canadian Bankers Association,[5] Bank of Montreal economist Doug Porter,[4] the Canadian Chamber of Commerce,[6] and the Canadian Taxpayers Federation[7] also supported this tax policy. In 2015 South Africa introduced TFSA accounts to encourage low to middle-class citizens to save money.

text: Canadian features[edit]

text: The TFSA is an account in which Canadian residents 18 years and older can save or invest. Income earned on contributions is not taxed. The TFSA account-holder may withdraw money from the account at any time, free of taxes.

text: Contribution room[edit]

text: The maximum annual contribution room for each year prior to 2013 was $5,000 per year. Beginning in 2013 it was increased to $5,500 per year.[8] The $5,500 annual contribution limit was indexed to the Consumer Price Index (CPI), in $500 increments, in order to account for inflation.[9]

text: The 2015 federal budget raised the contribution limit to $10,000, and eliminated indexation for inflation, beginning with the 2015 tax year.[10] However, in December 2015 a newly elected government proposed to restore the pre-2015 contribution limit of $5,500 for 2016, which will be indexed for inflation after that.[11][12][13]

text: As of January 1, 2018, the total cumulative contribution room for a TFSA is $57,500 for those who have been 18 years or older and residents of Canada for all eligible years.

text:
Years
TFSA Annual Limit
Cumulative Total

2009–2012
$5,000
$20,000

2013–2014
$5,500
$31,000

2015
$10,000[14]
$41,000

2016–2018
$5,500
$57,500

text: Any unused contribution room under the cap can be carried forward to subsequent years, without any upward limit.[15]

text: Eligible investments[edit]

text: A TFSA can hold any investments that are RRSP-eligible, including publicly traded shares on eligible exchanges, eligible shares of private corporations, certain debt obligations, instalment receipts, money denominated in any currency, trust interests including mutual funds and real estate investment trusts, annuity contracts, warrants, rights and options, registered investments, royalty units, partnership units, and depository receipts.[16]

text: Creditor protection[edit]

text: This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (September 2017) (Learn how and when to remove this template message)

text: Assets within a TFSA are not protected from creditors in the event of bankruptcy or a financial judgement that results from legal proceedings against the account-holder, whereas those within an RRSP are protected. Unless the investments in the TFSA are in a segregated fund (which then follows the Insurance act rules).

text: Over-contributions[edit]

text: A withdrawal in the year will increase the available contribution room, not in the current calendar year, but on January 1 of the following year. An over-contribution may occur when an individual (who has already maximized his TFSA contributions) might have the mistaken belief that a withdrawal from the TFSA will immediately create contribution room and 're-contribute' the withdrawn funds later in the same calendar year.

text: In the 2012 tax year CRA sent notices to about 74,000 taxpayers about TFSA over-contributions, compared to about nine million TFSAs existing at the end of 2012. About 76,000 notices were sent in 2011 and 103,000 in 2010.[17]

text: Foreign dividend withholding tax[edit]

text: Unlike an RRSP, a TFSA is not considered by the United States Internal Revenue Service to be a pension plan. Therefore, the tax treaty between the U.S. and Canada foregoing the U.S. withholding tax on dividends in registered pension plans does not apply to TFSA accounts, subjecting Canadians in most cases to a 15% U.S. tax withheld on dividends paid on shares of U.S. corporations. The tax withheld cannot be credited against other payable taxes as would be the case with non-registered accounts.

text: To get around this problem, one exchange-traded fund manager, Horizons ETFs Group, offers an ETF that uses swap contracts to replicate the return of the underlying dividend-paying stocks in the fund without actually holding any of those stocks. However, due to the fees charged by the counterparty to the swap agreement, as well as the fund's own management fee, its expenses exceed the actual withholding tax payable for the underlying stocks, if those were to be held directly in the TFSA.[18][19][20][21][22][23]

text: Risks for U.S. citizens and U.S residents[edit]

text: Canadian mutual funds held in TFSAs are generally considered by the IRS to be investments in a passive foreign investment company (PFIC), and must be reported as such (on form 8621) by U.S. citizens. PFICs can be very disadvantageous as, absent certain elections, "excess" distributions are always taxed at the highest marginal rate. Also, income is averaged over the duration of the investment, and interest is then charged from the date the income is deemed to have occurred, resulting in effective tax rates as high as 50% or more.[24][25] The TFSA may also be a grantor foreign trust from the perspective of the U.S. U.S. citizens with a grantor foreign trust are required to file IRS Forms 3520A (due March 15) and 3520 (due at the same time as Form 1040). These forms are both complicated and both involve potentially large penalties for late filing. Like other non-U.S. accounts the TFSA may also need to be included on a U.S. citizen's FBAR and tax-FBAR. Earnings inside the TFSA are taxed by the U.S.

text: South African features[edit]

text: The lifetime contribution limit is R500000 and the annual limit is R33000.[26]

text: Comparison to RRSP[edit]

text: This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (October 2014) (Learn how and when to remove this template message)

text: The tax treatment of a TFSA is the opposite of a Registered Retirement Savings Plan (RRSP). There is an income tax deduction for contributions to an RRSP, and withdrawals of contributions and investment income are all taxable. In contrast, there is no tax deduction for contributions to a TFSA, and there is no tax on withdrawals of investment income or contributions from the account.

text: Unlike an RRSP, which must be withdrawn before the holder turns 71, the TFSA does not expire.

text: If an account-holder withdraws funds from a TFSA, his or her contribution room is increased by that amount on the 1st of January after the withdrawal. In an RRSP, the contribution room is not increased to reflect withdrawals.

text: The Canada Revenue Agency (CRA) describes the difference between a TFSA and an RRSP as follows: "An RRSP is primarily intended for retirement. The TFSA is like an RRSP for everything else in your life." Interest paid on money borrowed to invest in either TFSA or RRSP is not tax deductible.[27]

text: Similar accounts in other countries[edit]

text: The TFSA is similar to a Roth Individual Retirement Arrangement in United States, although the TFSA has fewer restrictions.[clarification needed][28] In the UK, similar tax advantages have been available in Individual Savings Accounts since 1999.[29]