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Mariah Carbone
Mariah Suzanne Carbone is an American geophysicist who is a professor of Geosciences at the Center for ecosystem science and society, Northern Arizona University. She studies terrestrial ecosystems and how they respond to environmental change. Early life and education Carbone was an undergraduate student at Wesleyan University where she played women's soccer for the Wesleyan Cardinals. She moved to the University of California, Irvine for doctoral research, supervised by Susan Trumbore. Her thesis investigated ecosystem respiration and the residence time of the products of photosynthesis. Research and career Carbone studies how terrestrial ecosystems respond to environmental change, and how these ecosystems impact the Earth's climate. She makes use of isotope tracers to understand carbon cycling through plants and soils. This allows Carbone to understand how increasing levels of carbon dioxide will influence terrestrial ecosystems. Investigating the fate of carbon in terre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Arizona University
Northern Arizona University (NAU) is a public research university based in Flagstaff, Arizona. It was founded in 1899 as the final public university established in the Arizona Territory, 13 years before Arizona was admitted as the 48th state. NAU is one of the three universities governed by the Arizona Board of Regents and accredited by the Higher Learning Commission. As of fall 2022, 28,090 students were enrolled at NAU with 21,411 at the Flagstaff campus. The university is divided into seven academic colleges offering about 130 undergraduate degrees, 100 graduate programs, and various academic certificates. Students can take classes and conduct research in Flagstaff, online, and at more than 20 statewide locations, including the Phoenix Biomedical Campus. The university is classified among "R2: Doctoral Universities – High research activity" and ranked No. 183 in the National Science Foundation (NSF) national research rankings for fiscal year 2020. NAU's astronomy facult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate
Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorological variables that are commonly measured are temperature, humidity, atmospheric pressure, wind, and precipitation. In a broader sense, climate is the state of the components of the climate system, including the atmosphere, hydrosphere, cryosphere, lithosphere and biosphere and the interactions between them. The climate of a location is affected by its latitude/longitude, terrain, altitude, land use and nearby water bodies and their currents. Climates can be classified according to the average and typical variables, most commonly temperature and precipitation. The most widely used classification scheme was the Köppen climate classification. The Thornthwaite system, in use since 1948, incorporates evapotranspiration along with temperature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wild Fire
Wildfire is a fire in an area of combustible vegetation that occurs in the countryside or rural areas. Wildfire or Wild Fire may also refer to: People * "Wildfire", Chippewa name of sculptor Edmonia Lewis (c. 1844–1907) Arts, entertainment, and media Fictional entities *Wildfire (Drake Burroughs), a DC Comics superhero and member of the Legion of Super-Heroes * Wildfire (Carol Vance Martin), a Quality Comics female superhero from the 1940s * Wildfire, a flammable substance similar to Greek fire, featured in George R. R. Martin's fantasy novel series, ''A Song of Ice and Fire'', and its TV adaptation, ''Game of Thrones'' * ''Wildfire'', a spaceship capable of crossing universes in the British TV miniseries ''Red Dwarf'' * Wildfire, a biological facility in ''The Andromeda Strain'' * Wildfire, a playable "Trap Master" character in '' Skylanders: Trap Team'' Films * ''Wildfire'' (1915 film), a 1915 silent film * ''Wildfire'' (1925 film), a 1925 silent film * ''Wildfire'' (194 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territories of the United States by population, most populous U.S. state and the List of U.S. states and territories by area, 3rd largest by area. It is also the most populated Administrative division, subnational entity in North America and the 34th most populous in the world. The Greater Los Angeles area and the San Francisco Bay Area are the nation's second and fifth most populous Statistical area (United States), urban regions respectively, with the former having more than 18.7million residents and the latter having over 9.6million. Sacramento, California, Sacramento is the state's capital, while Los Angeles is the List of largest California cities by population, most populous city in the state and the List of United States cities by population, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redwood Tree
Sequoioideae, popularly known as redwoods, is a subfamily of coniferous trees within the family Cupressaceae. It includes the largest and tallest trees in the world. Description The three redwood subfamily genera are '' Sequoia'' from coastal California and Oregon, ''Sequoiadendron'' from California's Sierra Nevada, and ''Metasequoia'' in China. The redwood species contains the largest and tallest trees in the world. These trees can live for thousands of years. Threats include logging, fire suppression, climate change, illegal marijuana cultivation, and burl poaching. Only two of the genera, ''Sequoia'' and ''Sequoiadendron'', are known for massive trees. Trees of ''Metasequoia'', from the single living species ''Metasequoia glyptostroboides'', are much smaller. Taxonomy and evolution Multiple studies of both morphological and molecular characters have strongly supported the assertion that the Sequoioideae are monophyletic. Most modern phylogenies place ''Sequoia'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Weapons Testing
Nuclear weapons tests are experiments carried out to determine nuclear weapons' effectiveness, Nuclear weapon yield, yield, and explosive capability. Testing nuclear weapons offers practical information about how the weapons function, how detonations are affected by different conditions, and how personnel, structures, and equipment are affected when subjected to Nuclear explosion, nuclear explosions. However, nuclear testing has often been used as an indicator of scientific and military strength. Many tests have been overtly political in their intention; most List of countries with nuclear weapons, nuclear weapons states publicly declared their nuclear status through a nuclear test. The first nuclear device was detonated as a test by the United States at the Trinity site in New Mexico on July 16, 1945, with a yield approximately TNT equivalent, equivalent to 20 kilotons of TNT. The first thermonuclear weapon technology test of an engineered device, codenamed "Ivy Mike", was teste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon-14
Carbon-14, C-14, or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues (1949) to date archaeological, geological and hydrogeological samples. Carbon-14 was discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, California. Its existence had been suggested by Franz N. D. Kurie, Franz Kurie in 1934. There are three naturally occurring isotopes of carbon on Earth: carbon-12 (), which makes up 99% of all carbon on Earth; carbon-13 (), which makes up 1%; and carbon-14 (), which occurs in trace amounts, making up about 1 or 1.5 atoms per 1012 atoms of carbon in the atmosphere. Carbon-12 and carbon-13 are both stable, while carbon-14 is unstable and has a half-life of 5,730 ± 40 years. Carbon-14 decays into nitrogen-14 () through bet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bomb Pulse
The bomb pulse is the sudden increase of carbon-14 (14C) in the Earth's atmosphere due to the hundreds of aboveground nuclear bombs tests that started in 1945 and intensified after 1950 until 1963, when the Limited Test Ban Treaty was signed by the United States, the Soviet Union and the United Kingdom. These hundreds of blasts were followed by a doubling of the relative concentration of 14C in the atmosphere. We discuss “relative concentration”, because measurements of 14C levels by mass spectrometers are most accurately made by comparison to another carbon isotope, often the common isotope 12C. Isotope abundance ratios are not only more easily measured, they are what 14C carbon daters want, since it is the fraction of carbon in a sample that is 14C, not the absolute concentration, that is of interest in dating measurements. The figure shows how the fraction of carbon in the atmosphere that is 14C, of order only a part per trillion, has changed over the past several decades f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accelerator Mass Spectrometry
Accelerator mass spectrometry (AMS) is a form of mass spectrometry that accelerates ions to extraordinarily high kinetic energies before mass analysis. The special strength of AMS among the mass spectrometric methods is its power to separate a rare isotope from an abundant neighboring mass ("abundance sensitivity", e.g. 14C from 12C). The method suppresses molecular isobars completely and in many cases can separate atomic isobars (e.g. 14N from 14C) also. This makes possible the detection of naturally occurring, long-lived radio-isotopes such as 10Be, 36Cl, 26Al and 14C. Their typical isotopic abundance ranges from 10−12 to 10−18. AMS can outperform the competing technique of decay counting for all isotopes where the half-life is long enough. Other advantages of AMS include its short measuring time as well as its ability to detect atoms in extremely small samples. The method Generally, negative ions are created (atoms are ionized) in an ion source. In for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon-14
Carbon-14, C-14, or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues (1949) to date archaeological, geological and hydrogeological samples. Carbon-14 was discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, California. Its existence had been suggested by Franz N. D. Kurie, Franz Kurie in 1934. There are three naturally occurring isotopes of carbon on Earth: carbon-12 (), which makes up 99% of all carbon on Earth; carbon-13 (), which makes up 1%; and carbon-14 (), which occurs in trace amounts, making up about 1 or 1.5 atoms per 1012 atoms of carbon in the atmosphere. Carbon-12 and carbon-13 are both stable, while carbon-14 is unstable and has a half-life of 5,730 ± 40 years. Carbon-14 decays into nitrogen-14 () through bet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...—its atom making four electrons available to form covalent bond, covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, Carbon-12, C and Carbon-13, C being stable, while Carbon-14, C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the Timeline of chemical element discoveries#Ancient discoveries, few elements known since antiquity. Carbon is the 15th Abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the Abundance of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flux
Flux describes any effect that appears to pass or travel (whether it actually moves or not) through a surface or substance. Flux is a concept in applied mathematics and vector calculus which has many applications to physics. For transport phenomena, flux is a vector quantity, describing the magnitude and direction of the flow of a substance or property. In vector calculus flux is a scalar quantity, defined as the surface integral of the perpendicular component of a vector field over a surface. Terminology The word ''flux'' comes from Latin: ''fluxus'' means "flow", and ''fluere'' is "to flow". As ''fluxion'', this term was introduced into differential calculus by Isaac Newton. The concept of heat flux was a key contribution of Joseph Fourier, in the analysis of heat transfer phenomena. His seminal treatise ''Théorie analytique de la chaleur'' (''The Analytical Theory of Heat''), defines ''fluxion'' as a central quantity and proceeds to derive the now well-known express ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
