Carbon dioxide. Carbon dioxide (chemical formula CO2) is a naturally occurring chemical compound composed of 2 oxygen atoms each covalently double bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state, as a trace gas at a concentration of 0.039 per cent by volume. The environmental effects of carbon dioxide are of significant interest.
Atmospheric carbon dioxide is the primary source of carbon in life on Earth and its concentration in Earth's pre-industrial atmosphere since late in the Precambrian eon was regulated by photosynthetic organisms. Carbon dioxide is an important greenhouse gas; burning of carbon-based fuels since the industrial revolution has rapidly increased the concentration, leading to global warming. History Chemical and physical properties Structure and bonding The carbon dioxide molecule is linear and centrosymmetric. In aqueous solution The hydration equilibrium constant of carbonic acid is (at 25 °C). .
Uses. Wastewater. Wastewater treatment plant in Cuxhaven, Germany Wastewater, also written as waste water, is any water that has been adversely affected in quality by anthropogenic influence. Municipal wastewater is usually conveyed in a combined sewer or sanitary sewer, and treated at a wastewater treatment plant. Treated wastewater is discharged into receiving water via an effluent sewer. Wastewaters generated in areas without access to centralized sewer systems rely on on-site wastewater systems. These typically comprise a septic tank, drain field, and optionally an on-site treatment unit. Sewage is the subset of wastewater that is contaminated with feces or urine, but is often used to mean any wastewater.
Sewerage is the physical infrastructure, including pipes, pumps, screens, channels etc. used to convey sewage from its origin to the point of eventual treatment or disposal. Origin Wastewater or sewage can come from (text in brackets indicates likely inclusions or contaminants): Treatment Avatar Land. History Design Attractions A flying E ticket simulator attraction, where guests will learn to fly with a mountain Banshee.A boat ride attraction showcasing the native fauna and flora of Pandora. It may include small drops. Location Avatar Land is being built in the former location of Camp Minnie-Mickey, which was originally earmarked for the Beastly Kingdom, a never-built themed land which would have been based around mythological creatures. See also References ^ Jump up to: a b c Staggs, Tom. External links Official announcement at the Disney Parks Blog.
Pillow lava. Recently formed pillow lava, off Hawaii Cross-section of pillow lava near Oamaru, New Zealand Pillow lavas are lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava under water, or subaqueous extrusion. Pillow lavas in volcanic rock are characterized by thick sequences of discontinuous pillow-shaped masses, commonly up to one metre in diameter. They form the upper part of 'Layer 2' of normal oceanic crust.
Composition Pillow lavas are commonly of basaltic composition, although pillows formed of komatiite, picrite, boninite, basaltic andesite, andesite or even dacite are known. In general the more intermediate the composition, the larger the pillows, due to the increase in viscosity of the erupting lava. Occurrence Pillow lavas are also found associated with some subglacial volcanoes at an early stage of an eruption. Formation Use as a 'Way-up' criterion See also Pillow basalt References
Intertidal wetland. An intertidal wetland is an area along a shoreline that is exposed to air at low tide and submerged at high tide. This type of wetland is defined by an intertidal zone and includes its own intertidal ecosystems. Description The main types of intertidal wetlands are mudflats (e.g., mangrove swamps) and salt marshes. The mangrove swamps are encountered along tropical shores and are characterized by tree vegetation, while salt marshes are mostly found in temperate zones and are mostly grass ecosystems. Intertidal wetlands are commonly encountered in most estuaries. See also Tidal marsh References Anoxia. The term anoxia means a total depletion in the level of oxygen, an extreme form of hypoxia or "low oxygen". The terms anoxia and hypoxia are used in various contexts: Inert gas.
An inert gas is a gas which does not undergo chemical reactions under a set of given conditions. The noble gases and nitrogen often do not react with many substances. Inert gases are used generally to avoid unwanted chemical reactions degrading a sample. These undesirable chemical reactions are often oxidation and hydrolysis reactions with the oxygen and moisture in air. The term inert gas is context-dependent because nitrogen gas and several of the noble gases can be made to react under certain conditions.
Purified nitrogen and argon gases are most commonly used as inert gases due to their high natural abundance (78% N2, 1% Ar in air) and low relative cost. Unlike noble gases, an inert gas is not necessarily elemental and is often a compound gas. Production The inert gases are obtained by fractional distillation of air. Applications Because of the non-reactive properties of inert gases they are often useful to prevent undesirable chemical reactions from taking place. Shale gas. As of 2013, the US, Canada, and China are the only countries producing shale gas in commercial quantities. The US and Canada are the only countries where shale gas is a significant part of the gas supply.
Shale gas is natural gas that is found trapped within shale formations. Shale gas has become an increasingly important source of natural gas in the United States since the start of this century, and interest has spread to potential gas shales in the rest of the world. In 2000 shale gas provided only 1% of U.S. natural gas production; by 2010 it was over 20% and the U.S. government's Energy Information Administration predicts that by 2035, 46% of the United States' natural gas supply will come from shale gas. The Obama administration believes that increased shale gas development will help reduce greenhouse gas emissions (in 2012, US carbon dioxide emissions dropped to a 20-year low).
Human and public health will both benefit from shale gas displacing coal burning. US Tropospheric ozone. Seasonal average vertical columns of tropospheric ozone in Dobson units over the period 1979 to 2000. In June to August photochemical ozone production causes very high concentrations over the East Coast of the USA and China. Ozone (O3) is a constituent of the troposphere (it is also an important constituent of some regions of the stratosphere commonly known as the ozone layer). The troposphere extends from the surface of the Earth to between 12 and 20 kilometers above the surface of the Earth and consists of many layers. Ozone is more concentrated above the mixing layer, or ground layer. Ground-level ozone, though less concentrated than ozone aloft, is more of a problem because of its health effects. Photochemical and chemical reactions involving it drive many of the chemical processes that occur in the atmosphere by day and by night.
Tropospheric ozone is a greenhouse gas and initiates the chemical removal of methane and other hydrocarbons from the atmosphere. Measurement Afterglow. After the eruption of the volcano Krakatoa in 1883, a remarkable series of red sunsets appeared worldwide. These were due to an enormous amount of exceedingly fine dust blown to a great height by the volcano's explosion, and then globally diffused by the high atmospheric currents. Edvard Munch's painting The Scream possibly depicts an afterglow during this period. An afterglow on Krakow's housing estate See also References See also
Aerostatics. Aerostatics is the study of gases that are not in motion. The corresponding study of gases in motion is called aerodynamics. It is a subfield of fluid statics. Aerostatics studies density allocation, especially in air. One of the applications of this is the barometric formula. An aerostat is a lighter than air craft, such as an airship or balloon, which uses the principles of aerostatics to float. Fields of study See also Aeronautics. Carbon cycle. This diagram of the fast carbon cycle shows the movement of carbon between land, atmosphere, and oceans in billions of tons of carbon per year. Yellow numbers are natural fluxes, red are human contributions in billions of tons of carbon per year. White numbers indicate stored carbon. The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth.
Along with the nitrogen cycle and the water cycle, the carbon cycle comprises a sequence of events that are key to making the Earth capable of sustaining life; it describes the movement of carbon as it is recycled and reused throughout the biosphere. The global carbon budget is the balance of the exchanges (incomes and losses) of carbon between the carbon reservoirs or between one specific loop (e.g., atmosphere ↔ biosphere) of the carbon cycle.
Relevance for the global climate Main components Atmosphere Terrestrial biosphere Controlled atmosphere. A controlled atmosphere is an agricultural storage method. An atmosphere in which oxygen, carbon dioxide and nitrogen concentrations as well as temperature and humidity are regulated. Two major classes of commodity can be stored in controlled atmosphere: Dry commodities such as grains, legumes and oilseed. In these commodities the primary aim of the atmosphere is usually to control insect pests. Most insects cannot exist indefinitely without oxygen or in conditions of raised (greater than approximately 30%) carbon dioxide. Controlled atmosphere treatments of grains can be a fairly slow process taking up to several weeks at lower temperatures (less than 15°C).
See also References Jump up ^ Annis, P.C. and Morton, R. 1997.The acute mortality effects of carbon dioxide on various life stages of Sitophilus oryzae. Rod (optics) Long exposure photograph of moths showing exaggerated rod effect Various paranormal interpretations appeared in the popular culture, and one of the more outspoken proponents of rods as alien life forms is Jose Escamilla, who claims to have been the first to film them on March 19, 1994 at Roswell, New Mexico, while attempting to film a UFO. Since then, Escamilla has made additional videos and embarked on lecture tours to promote his claims. The Straight Dope columnist Cecil Adams called rods a hoax "where unscrupulous people are exploiting a gullible public for profit", and said that investigators have shown that rods are mere tricks of light which result from how images (primarily video images) of flying insects are recorded and played back.
In particular, the fast passage before the camera of an insect flapping its wings has been shown to produce rodlike effects, due to motion blur, if the camera is shooting with relatively long exposure times. Ozone. Ozone /ˈoʊzoʊn/ (systematically named 1λ1,3λ1-trioxidane and μ-oxidodioxygen), or trioxygen, is an inorganic molecule with the chemical formula O 3(μ-O) (also written [O(μ-O)O] or O 3). It is a pale blue gas with a distinctively pungent smell.
It is an allotrope of oxygen that is much less stable than the diatomic allotrope O 2, breaking down in the lower atmosphere to normal dioxygen. Ozone is formed from dioxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 ppm of the atmosphere. Ozone's odor is sharp, reminiscent of chlorine, and detectable by many people at concentrations of as little as 10 ppb in air. Ozone is a powerful oxidant (far more so than dioxygen) and has many industrial and consumer applications related to oxidation. Nomenclature The trivial name ozone is the most commonly used and preferred IUPAC name. History   Bog. Marsh. Mire. Tropical rainforest. Waste container. Effects of the automobile on societies. Water. Oil sludge. Environmental impact of aviation.
Dead zone (ecology)