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Dobson Spectrometer
The Dobson spectrophotometer, also known as Dobsonmeter, Dobson spectrometer, or just Dobson is one of the earliest instruments used to measure atmospheric ozone. History The Dobson spectrometer was invented in 1924 by Gordon Dobson. A history of the development of the instrument is here and an example of one of Dobson's own instruments remains on display in the University of Oxford Department of Physics. Operation Dobson spectrophotometers can be used to measure both total column ozone and profiles of ozone in the atmosphere. Ozone is tri-atomic oxygen, O3; ozone molecules absorb harmful UV light in the atmosphere before it reaches the surface of the earth. No UVC radiation penetrates to the ground as it is absorbed in the ozone-oxygen cycle. However some longer-wave and less harmful UVB and most of the UVA is not absorbed as ozone is less opaque to these frequencies, so they penetrate to the ground level of Earth in higher quantities. The sources of light used may vary. ...
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Umkehr Effect
The Umkehr is the time variation of the ratio of the scattered intensity at two different wavelengths. The word means 'reversal' in German. The Umkehr effect is observed when measurements are made with ultraviolet spectrophotometer of the ratio of the zenith sky light intensities of two wavelengths in the solar ultraviolet when the sun is near the horizon. The shorter of two wavelengths (intensity ''I'') is strongly absorbed and the other (intensity ''I' '') is weakly absorbed. If the value of log(''I''/''I' '') is plotted against the sun's zenith angle, it is observed that this log-intensity ratio decreases as the zenith angle increases until a minimum is reached for a zenith angle of about 8° (when the wavelengths are 3114 and 3324 A). This effect was first noticed by Götz in 1930. The Umkehr measurement is known as customarily N-value and is given by the logarithm base 10 of the ratio of cloudless zenith sky intensities at two different wavelengths scaled by a multiplicative fa ...
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Spectrometers
A spectrometer () is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the spectral components are somehow mixed. In visible light a spectrometer can separate white light and measure individual narrow bands of color, called a spectrum. A mass spectrometer measures the spectrum of the masses of the atoms or molecules present in a gas. The first spectrometers were used to split light into an array of separate colors. Spectrometers were developed in early studies of physics, astronomy, and chemistry. The capability of spectroscopy to determine chemical composition drove its advancement and continues to be one of its primary uses. Spectrometers are used in astronomy to analyze the chemical composition of stars and planets, and spectrometers gather data on the origin of the universe. Examples of spectrometers are d ...
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Alan West Brewer
Alan West Brewer (1915 – 21 November 2007) was a Britanno-Canadian physicist and climatologist. Born in Montreal, Quebec, Canada and raised in Derby, England, he earned a scholarship to study physics at the University College London. He received his M.Sc. there, and began to work for the Met Office in 1937. During World War II, he researched contrails for the Royal Air Force, making the discovery that the stratosphere is much drier than had been presumed. Later this observation led to the development of Brewer-Dobson circulation. Brewer worked at the Subdepartment of Atmospheric, Oceanic and Planetary Physics, University of Oxford from 1948 until 1962, when he became a professor at University of Toronto. In 1977, Brewer retired from the University of Toronto, returning to England, in Devon Devon ( , historically known as Devonshire , ) is a ceremonial and non-metropolitan county in South West England. The most populous settlement in Devon is the city of Plymouth ...
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Kunming
Kunming (; ), also known as Yunnan-Fu, is the capital and largest city of Yunnan province, China. It is the political, economic, communications and cultural centre of the province as well as the seat of the provincial government. The headquarters of many of Yunnan's large businesses are in Kunming. It was important during World War II as a Chinese military center, American air base, and transport terminus for the Burma Road. In the middle of the Yunnan–Guizhou Plateau, Kunming is at an altitude of above sea level and a latitude just north of the Tropic of Cancer. As of 2020 census, Kunming had a total population of 8,460,088 inhabitants, of whom 5,604,310 lived in its built-up (or metro) area made of all urban districts but Jinning, not conurbated yet. It is at the northern edge of Dian Lake, surrounded by temples and lake-and-limestone hill landscapes. Kunming consists of an old, previously walled city, a modern commercial district, residential zones and university areas. ...
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Svalbard
Svalbard ( , ), also known as Spitsbergen, or Spitzbergen, is a Norwegian archipelago in the Arctic Ocean. North of mainland Europe, it is about midway between the northern coast of Norway and the North Pole. The islands of the group range from 74° to 81° north latitude, and from 10° to 35° east longitude. The largest island is Spitsbergen, followed by Nordaustlandet and . The largest settlement is Longyearbyen. The islands were first used as a base by the whalers who sailed far north in the 17th and 18th centuries, after which they were abandoned. Coal mining started at the beginning of the 20th century, and several permanent communities were established. The Svalbard Treaty of 1920 recognizes Norwegian sovereignty, and the 1925 Svalbard Act made Svalbard a full part of the Kingdom of Norway. They also established Svalbard as a free economic zone and a demilitarized zone. The Norwegian Store Norske and the Russian remain the only mining companies in place. Res ...
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Ny-Ålesund
Ny-Ålesund ("New Ålesund") is a small town in Oscar II Land on the island of Spitsbergen in Svalbard, Norway. It is situated on the Brøgger peninsula ( Brøggerhalvøya) and on the shore of the bay of Kongsfjorden. The company town is owned and operated by Kings Bay, which provides facilities for permanent research activities by 19 institutions from 11 countries. The town is ultimately owned by the Ministry of Climate and Environment and is not incorporated (i.e. is not recognised as a town by the Norwegian government). Ny-Ålesund has an all-year permanent population of 30 to 35, with the summer population reaching 114. Its facilities include Ny-Ålesund Airport, Hamnerabben, Svalbard Rocket Range, a port and Ny-Ålesund Town and Mine Museum, as well as a number of buildings dedicated to research and environmental monitoring activities. It is the northernmost functional civilian settlement in the world. The town was founded in 1917 by Peter Brandal and his mining company, Ki ...
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Norwegian Polar Institute
The Norwegian Polar Institute (NPI; no, Norsk Polarinstitutt) is Norway's central governmental institution for scientific research, mapping and environmental monitoring in the Arctic and the Antarctic. The NPI is a directorate under Norway's Ministry of Climate and Environment. The institute advises Norwegian authorities on matters concerning polar environmental management and is the official environmental management body for Norwegian activities in Antarctica. Activities The institute's activities are focused on environmental research and management in the polar regions. The NPI's researchers investigate biodiversity, climate and environmental toxins in the Arctic and Antarctic, and in this context the institute equips and organizes large-scale expeditions to both polar regions. The institute contributes to national and international climate work, and is an active contact point for the international scientific community. The institute collects and analyses data on the environm ...
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Ozone Hole
Ozone depletion consists of two related events observed since the late 1970s: a steady lowering of about four percent in the total amount of ozone in Earth's atmosphere, and a much larger springtime decrease in stratospheric ozone (the ozone layer) around Earth's polar regions. The latter phenomenon is referred to as the ozone hole. There are also springtime polar tropospheric ozone depletion events in addition to these stratospheric events. The main causes of ozone depletion and the ozone hole are manufactured chemicals, especially manufactured halocarbon refrigerants, solvents, propellants, and foam-blowing agents (chlorofluorocarbons (CFCs), HCFCs, halons), referred to as ozone-depleting substances (ODS). These compounds are transported into the stratosphere by turbulent mixing after being emitted from the surface, mixing much faster than the molecules can settle. Once in the stratosphere, they release atoms from the halogen group through photodissociation, which catalyze t ...
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British Antarctic Survey
The British Antarctic Survey (BAS) is the United Kingdom's national polar research institute. It has a dual purpose, to conduct polar science, enabling better understanding of global issues, and to provide an active presence in the Antarctic on behalf of the UK. It is part of the Natural Environment Research Council (NERC). With over 400 staff, BAS takes an active role in Antarctic affairs, operating five research stations, one ship and five aircraft in both polar regions, as well as addressing key global and regional issues. This involves joint research projects with over 40 UK universities and more than 120 national and international collaborations. Having taken shape from activities during World War II, it was known as the Falkland Islands Dependencies Survey until 1962. History Operation Tabarin was a small British expedition in 1943 to establish permanently occupied bases in the Antarctic. It was a joint undertaking by the Admiralty and the Colonial Office. At the end of t ...
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Joe Farman
Joseph Charles Farman CBE (7 August 193011 May 2013) was a British geophysicist who worked for the British Antarctic Survey. Together with Brian Gardiner and Jon Shanklin, he published the discovery of the ozone hole over Antarctica, having used Dobson ozone spectrophotometers. Their results were first published on 16 May 1985. Education He was educated at Norwich School, where he was a prefect in Coke House, and Corpus Christi College, Cambridge, where he gained an undergraduate degree in Natural Sciences. Awards He received numerous honours for this discovery, including the Society of Chemical Industry (SCI) Environment Medal, the Chree Medal and Prize, membership of the Global 500 Roll of Honour, and a CBE The Most Excellent Order of the British Empire is a British order of chivalry, rewarding contributions to the arts and sciences, work with charitable and welfare organisations, and public service outside the civil service. It was established o ... in the 2000 New Year ...
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Pollutants
A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like oil) or anthropogenic in origin (i.e. manufactured materials or byproducts from biodegradation). Pollutants result in environmental pollution or become public health concerns when they reach a concentration high enough to have significant negative impacts. A pollutant may cause long- or short-term damage by changing the growth rate of plant or animal species, or by interfering with human amenities, comfort, health, or property values. Some pollutants are biodegradable and therefore will not persist in the environment in the long term. However, the degradation products of some pollutants are themselves polluting such as the products DDE and DDD produced from the degradation of DDT. Pollution has widespread negative impacts on the environ ...
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