Information AboutSmog |
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London was notorious for its thick smogs, or "pea-soupers", a fact that is often recreated to add an air of mystery to a period Costume Drama .]] Smog is a kind of Air Pollution - the name is a Portmanteau of Smoke and Fog . Classic smog results from large amounts of coal burning in an area and is caused by a mixture of smoke and Sulphur Dioxide . In the 1950s a new type of smog, known as Photochemical Smog , was first described. This is a noxious mixture of air pollutants including the following:
All of these chemicals are usually highly reactive and oxidizing. Due to this fact, photochemical smog is considered to be a problem of modern industrialization. Photochemical smog is a concern in most major urban centres but, because it travels with the wind, it can affect sparsely populated areas as well. Smog is caused by a reaction between sunlight and emissions mainly from human activity. Photochemical smog is the chemical reaction of sunlight, Nitrogen Oxides (NOx) and Volatile Organic Compound s (VOC's) in the atmosphere, which leaves airborne particles (called Particulate Matter ) and ground-level Ozone . Nitrogen oxides are released in the exhaust of Fossil Fuel -burning engines in Cars , trucks, Coal Power Plant s, and industrial manufacturing factories. VOC's are vapors released from Gasoline , Paint s, Solvent s, Pesticide s, and other Chemical s. Origin of term The term "smog" was first coined by Dr. Henry Antoine Des Voeux in his 1905 paper, “Fog and Smoke,” for a meeting of the Public Health Congress . The 26 July 1905 edition of the London newspaper ''Daily Graphic'' quoted Des Voeux, “ {Link without Title} e said it required no science to see that there was something produced in great cities which was not found in the country, and that was smoky fog, or what was known as ‘smog.’” The following day the newspaper stated that “Dr. Des Voeux did a public service in coining a new word for the London fog.” Areas affected Smog can form in almost any climate where industries or cities release large amounts of Air Pollution . However, it is worse during periods of warmer, sunnier weather when the upper air is warm enough to inhibit vertical circulation. It is especially prevalent in geologic basins encircled by hills or mountains. It often stays for an extended period of time over densely populated cities, such as London , Los Angeles , Mexico City , Athens , Beijing , Hong Kong or the Ruhr Area and can build up to dangerous levels. The high density of factories located in Mainland China has polluted Hong Kong . Now, Hong Kong's skyscrapers can barely be seen. London Even in the Middle Ages , concerns over air pollution were sufficient for Edward I to (briefly) ban the use of coal fires in London in 1273. In 1661, John Evelyn 's '' Fumifugium '' suggested burning fragrant wood instead of mineral coal, to reduce coughing. A ballad of the time describes how the smoke "does our lungs and spirits choke, Our hanging spoil, and rust our iron." Episodes of smog became common in London in the late 19th Century and were nicknamed "pea-soupers". The Great Smog Of 1952 darkened the skies over London and killed approximately 4,000 people in the short term (a further 8,000 died from its effects in the following weeks and months). Reluctant to admit that coal smoke was to blame, the British government initially blamed a Flu Epidemic . In 1956 the Clean Air Act introduced Smokeless Zone s to the capital. Only smokeless fuels could be used in these areas. Consequently, reduced Sulfur Dioxide levels made the intense and persistent London smog a thing of the past. Smog caused by traffic pollution, however, does occur in modern London. Health effects Smog is a problem in a number of cities and continues to harm human health Ground-level ozone is especially harmful for seniors, children, and people with heart and lung conditions such as Emphysema , Bronchitis , and Asthma [http://www.airnow.gov/index.cfm?action=health2.smog1#4 . It can inflame breathing passages, decreasing the lung's working capacity, and causing shortness of breath, pain when inhaling deeply, wheezing, and coughing. It can cause eye and nose irritation and dry out the protective membranes of the nose and throat and interfere with the body's ability to fight infection, increasing susceptibility to illness. Hospital admissions and respiratory deaths often increase during periods when ozone levels are high [http://www.cwac.net/air_pollution/ozone.html]. The U.S. ; 15.5 ppbv - 30.4ppb for CO and 0.65 ppbv - 1.24 {Link without Title} in the beige cloud bank behind Golden Gate Bridge ]] Natural causes An erupting Volcano can also emit high levels of Sulfur Dioxide , creating volcanic smog, or Vog . The burning of Forest s in Indonesia has on a number of occasions created prolonged smog-like Haze , which have extended to parts of Malaysia , Philippines , Singapore and Thailand . Cultural references The London "pea-soupers" earned the capital the nickname of "The Smoke". Similarly, Edinburgh was known as "Auld Reekie". The smogs feature in many London novels as a motif indicating hidden danger or a mystery, perhaps most overtly in Margery Allingham 's ''The Tiger in the Smoke'' (1952), but also in Dickens ' '' Bleak House '' (1852). {Link without Title} s he handed me into a fly after superintending the removal of my boxes, I asked him whether there 'Smog' or ' Smoggy ' has also come into use to describe a resident of Teesside (in North East England) or a supporter of Middlesbrough Football Club , due to the high concentration of chemical and heavy industry in the Teesside area. See also Notes and references
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