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Black Carbon
Chemically, black carbon (BC) is a component of fine particulate matter (PM ≤ 2.5 µm in aerodynamic diameter). Black carbon consists of pure carbon in several linked forms. It is formed through the incomplete combustion of fossil fuels, biofuel, and biomass, and is one of the main types of particle in both anthropogenic and naturally occurring soot. Black carbon causes human morbidity and premature mortality. Because of these human health impacts, many countries have worked to reduce their emissions, making it an easy pollutant to abate in anthropogenic sources. In climatology, black carbon is a climate forcing agent contributing to global warming. Black carbon warms the Earth by absorbing sunlight and heating the atmosphere and by reducing albedo when deposited on snow and ice (direct effects) and indirectly by interaction with clouds, with the total forcing of 1.1 W/m2. Black carbon stays in the atmosphere for only several days to weeks, whereas potent greenhouse gas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Black
Carbon black (subtypes are acetylene black, channel black, furnace black, lamp black and thermal black) is a material produced by the incomplete combustion of coal and coal tar, vegetable matter, or petroleum products, including fuel oil, fluid catalytic cracking tar, and ethylene cracking. Carbon black is a form of paracrystalline carbon that has a high surface-area-to-volume ratio, albeit lower than that of activated carbon. It is dissimilar to soot in its much higher surface-area-to-volume ratio and significantly lower (negligible and non-bioavailable) polycyclic aromatic hydrocarbon (PAH) content. However, carbon black can be used as a model compound for diesel soot to better understand how diesel soot behaves under various reaction conditions as carbon black and diesel soot have some similar properties such as particle sizes, densities, and copolymer adsorption abilities that contribute to them having similar behaviours under various reactions such as oxidation experiment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. It is a trace gas in Earth's atmosphere at 421 parts per million (ppm), or about 0.04% by volume (as of May 2022), having risen from pre-industrial levels of 280 ppm. Burning fossil fuels is the primary cause of these increased CO2 concentrations and also the primary cause of climate change.IPCC (2022Summary for policy makersiClimate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA Carbon dioxide is soluble in water and is found in groundwater, lakes, ice ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Depth
In physics, optical depth or optical thickness is the natural logarithm of the ratio of incident to ''transmitted'' radiant power through a material. Thus, the larger the optical depth, the smaller the amount of transmitted radiant power through the material. Spectral optical depth or spectral optical thickness is the natural logarithm of the ratio of incident to transmitted spectral radiant power through a material. Optical depth is dimensionless, and in particular is not a length, though it is a monotonically increasing function of optical path length, and approaches zero as the path length approaches zero. The use of the term "optical density" for optical depth is discouraged. In chemistry, a closely related quantity called "absorbance" or "decadic absorbance" is used instead of optical depth: the common logarithm of the ratio of incident to transmitted radiant power through a material, that is the optical depth divided by ln 10. Mathematical definitions Optical dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NOAA
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditions, charts the seas, conducts deep sea exploration, and manages fishing and protection of marine mammals and endangered species in the U.S. exclusive economic zone. Purpose and function NOAA's specific roles include: * ''Supplying Environmental Information Products''. NOAA supplies to its customers and partners information pertaining to the state of the oceans and the atmosphere, such as weather warnings and forecasts via the National Weather Service. NOAA's information services extend as well to climate, ecosystems, and commerce. * ''Providing Environmental Stewardship Services''. NOAA is a steward of U.S. coastal and marine environments. In coordination with federal, state, local, tribal and international authorities, NOAA manages the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aethalometer
An aethalometer is an instrument for measuring the concentration of optically absorbing (‘black’) suspended particulates in a gas colloid stream; commonly visualized as smoke or haze, often seen in ambient air under polluted conditions. The word aethalometer is derived from the Classical Greek verb ''aethaloun'', meaning "to blacken with soot". Principle of operation The gas stream (frequently ambient air) passes through a filter material which traps the suspended particulates, creating a deposit of increasing density. A light beam projected through the deposit is attenuated by those particles which are absorbing (‘black’) rather than scattering (‘white’). Measurements are made at successive regular time intervals. The increase in attenuation from one measurement to the next is proportional to the increase in the density of optically absorbing material on the filter: which, in turn, is proportional to the concentration of the material in the sampled air stream. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clean Air Act 1956
The Clean Air Act 1956 was an Act of the Parliament of the United Kingdom enacted principally in response to London's Great Smog of 1952. It was sponsored by the Ministry of Housing and Local Government in England and the Department of Health for Scotland, and was in effect until 1993. The Act introduced a number of measures to reduce air pollution. Primary among them was mandated movement toward smokeless fuels, especially in high-population ‘smoke control areas’ to reduce smoke pollution and sulphur dioxide from household fires. The Act also included measures that reduced the emission of gases, grit, and dust from chimneys and smoke-stacks. The Act was a significant milestone in the development of a legal framework to protect the environment. It was modified by later enactments, including the Clean Air Act 1968. The Act was repealed by the Clean Air Act 1993. Background London had long been noted for its pea soup fog. In 1880, meteorologist Rollo Russell wrote an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raman Spectroscopy
Raman spectroscopy () (named after Indian physicist C. V. Raman) is a spectroscopic technique typically used to determine vibrational modes of molecules, although rotational and other low-frequency modes of systems may also be observed. Raman spectroscopy is commonly used in chemistry to provide a structural fingerprint by which molecules can be identified. Raman spectroscopy relies upon inelastic scattering of photons, known as Raman scattering. A source of monochromatic light, usually from a laser in the visible, near infrared, or near ultraviolet range is used, although X-rays can also be used. The laser light interacts with molecular vibrations, phonons or other excitations in the system, resulting in the energy of the laser photons being shifted up or down. The shift in energy gives information about the vibrational modes in the system. Infrared spectroscopy typically yields similar yet complementary information. Typically, a sample is illuminated with a laser beam. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphite
Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large scale (300 kton/year, in 1989) for uses in pencils, lubricants, and electrodes. Under high pressures and temperatures it converts to diamond. It is a weak conductor of heat and electricity. Types and varieties Natural graphite The principal types of natural graphite, each occurring in different types of ore deposits, are * Crystalline small flakes of graphite (or flake graphite) occurs as isolated, flat, plate-like particles with hexagonal edges if unbroken. When broken the edges can be irregular or angular; * Amorphous graphite: very fine flake graphite is sometimes called amorphous; * Lump graphite (or vein graphite) occurs in fissure veins or fractures and appears as massive platy intergrowths of fibrous or acicular cryst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environmental Impact
Environmental issues are effects of human activity on the biophysical environment, most often of which are harmful effects that cause environmental degradation. Environmental protection is the practice of protecting the natural environment on the individual, organizational or governmental levels, for the benefit of both the environment and humans. Environmentalism is a social and environmental movement that addresses environmental issues through advocacy, legislation education, and activism. Environment destruction caused by humans is a global, ongoing problem. Water pollution also cause problems to marine life. Most scholars think that the project peak global world population of between 9-10 billion people, could live sustainably within the earth's ecosystems if human society worked to live sustainably within planetary boundaries. The bulk of environmental impacts are caused by the most wealthy populations in the globe consuming too much industrial goods. The UN Environmental ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Hansen
James Edward Hansen (born March 29, 1942) is an American adjunct professor directing the Program on Climate Science, Awareness and Solutions of the Earth Institute at Columbia University. He is best known for his research in climatology, his 1988 Congressional testimony on climate change that helped raise broad awareness of global warming, and his advocacy of action to avoid dangerous climate change. In recent years he has become a climate activist to mitigate the effects of global warming, on a few occasions leading to his arrest. Early life and education Hansen was born in Denison, Iowa, to James Ivan Hansen and Gladys Ray Hansen. He was trained in physics and astronomy in the space science program of James Van Allen at the University of Iowa. He obtained a B.A. in Physics and Mathematics with highest distinction in 1963, an M.S. in Astronomy in 1965 and a Ph.D. in Physics in 1967, all three degrees from the University of Iowa. He participated in the NASA graduate tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tihomir Novakov
Tihomir Novakov, Ph.D known also as Tica Novakov (March 16, 1929 – January 2, 2015) was a Serbian-born American physicist. As a scientist, Novakov is known for his black carbon, air quality, and climate change research. James Hansen dubbed him "the godfather of black carbon". Early life Novakov was born in Sombor, Serbia, in 1929. His father was a veterinarian and his mother was a homemaker. While in high school, Novakov began to build X-ray tubes and radios, furthering his scientific knowledge on his own. After graduating from the University of Belgrade with a PhD in nuclear physics, he taught at the University of Belgrade and worked at the Vinča Nuclear Institute. Novakov migrated to the United States in 1963 and began working as a research scientist at the Lawrence Berkeley National Laboratory. He later founded an Aerosol Research Group which traveled the world conducting research on climate change. Career In the late 1960s and early 1970s, Novakov's group was the first t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael Faraday
Michael Faraday (; 22 September 1791 – 25 August 1867) was an English scientist who contributed to the study of electromagnetism and electrochemistry. His main discoveries include the principles underlying electromagnetic induction, diamagnetism and electrolysis. Although Faraday received little formal education, he was one of the most influential scientists in history. It was by his research on the magnetic field around a conductor carrying a direct current that Faraday established the concept of the electromagnetic field in physics. Faraday also established that magnetism could affect rays of light and that there was an underlying relationship between the two phenomena.. the 1911 Encyclopædia Britannica. He similarly discovered the principles of electromagnetic induction, diamagnetism, and the laws of electrolysis. His inventions of electromagnetic rotary devices formed the foundation of electric motor technology, and it was largely due to his efforts t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
