Noise pollution is unwanted or harmful sound that intrudes upon human or other faunal activity. Noise pollution is almost entirely human generated, whether by machine sources or amplified sound of human creation. Approximately ninety percent of all such intrusive sound arises from such transport devices as motor vehicles, aircraft and rail activities. Noise pollution gives rise to an assortment of adverse human health effects as well as disruption of faunal activity. Regulation of noise pollution began in a systematic way in the United States with enactment of the Noise Control Act of 1972. Within the next 22 years a number of other national governments had emulated the U.S. initiative, including Netherlands (1979), France (1985), Spain (1993), and Denmark (1994). Noise pollution can also occur underwater, where man made sound may disrupt communication and echo-location for marine mammals and other fauna.
In the Arctic, people frequently see unique and beautiful optical phenomena. The atmospheric conditions that can lead to the development of these...
Nonpoint sourceLast Updated on 2013-05-23 00:00:00
A nonpoint source refers to a source of pollution from an origin other than a well defined point. The term is most often applied to air pollution, water pollution and noise pollution. Nonpoint pollution sources may be classified as either line sources, area sources, or less frequently as volume sources. The classic line source is a linear highway, which produces both air pollution and noise pollution. A classic area source is a parcel of land, which produces water pollution in the form of surface runoff containing excessive amounts of nitrates, phosphates, pesticides and herbicides.
The attention to nonpoint sources was heightened, when researchers realized that most human exposure to air and noise pollution derived from nonpoint sources. In the case of noise pollution, over ninety percent of environmental noise exposure worldwide arises from line sources .Less commonly,... More »
UK Department for Environment, Food and Rural AffairsLast Updated on 2012-04-30 00:00:00
The Department for Environment, Food and Rural Affairs (Defra) is the government department responsible for environmental protection, food production and standards, agriculture, fisheries and rural communities in the United Kingdom (UK). Formal agreements also establish the frameworks for co-operation between Defra and the Scottish Government, the Cabinet of the National Assembly for Wales and with representatives from the Northern Ireland Assembly, which have delegated responsibilities for these matters in their respective nations.
Defra also represents the UK at the European Union on agricultural, fisheries and environment matters and in other international negotiations on sustainable development and climate change, although a new Department of Energy and Climate Change was created in 2008 to take over this responsibility.
The headquarters of Defra are... More »
Atmospheric lapse rateLast Updated on 2011-10-16 00:00:00
The atmospheric lapse rate ( ) refers to the change of an atmospheric variable with a change of altitude, the variable being temperature unless specified otherwise (such as pressure, density or humidity). While usually applied to Earth's atmosphere, the concept of lapse rate can be extended to atmospheres (if any) that exist on other planets.
Lapse rates are usually expressed as the amount of temperature change associated with a specified amount of altitude change, such as 9.8 °Kelvin (K) per kilometer, 0.0098 °K per meter or the equivalent 5.4 °F per 1000 feet. If the atmospheric air cools with increasing altitude, the lapse rate may be expressed as a negative number. If the air heats with increasing altitude, the lapse rate may be expressed as a positive number.
Understanding of lapse rates is important in microscale air pollution dispersion... More »
Sowerby's beaked whaleLast Updated on 2011-05-02 00:00:00Sowerby's beaked whale (scientific name: Mesoplodon bidens) is is one of 21 species of beaked whales (Hyperoodontidae or Ziphiidae), medium-sized whales with distinctive, long and narrow beaks and dorsal fins set far back on their bodies. They are marine mammals within the order of cetaceans.
Relatively little is known about this cetacean, including what it eats, details of its growth, reproduction and social organization. Sowerby's beaked whale is a toothed whale and can be recognised as such by the single blowhole and the presence of teeth (rather than baleen). The lower jaw has a single pair of teeth (exposed only in adult males). The forehead rises at a shallow angle and has a slight bump. It has a distinct beak and the mouthline is curved down at rear.
It is a small beaked whale that can reach up to 5.5 meters in length. Sowerby's beaked whale has a charcoal grey dorsal and... More »
Dark side of insulationLast Updated on 2011-02-09 00:00:00Building insulation has become a modish activity in the western world since the 1980s. Considerable benefits can accrue in energy conservation, occupant comfort and reduction of noise pollution from external sources. A dark side of insulation arises, however, from its trapping of radon gas, cigarette smoke, household sprays and other toxins within the enhanced imperviousness of the building skin. Furthermore, insulation can promote the entrapment of moisture, that in turn may increase the formation of molds and mildews, some of which contain toxic species.
Compounding the problem of trapping indoor air pollutants, some insulation techniques employ fibers and chemicals that themselves have adverse human health effects including toxicity risks. While use of asbestos has been a long known risk, there are a host of recently developed chemical substances and fibers that pose entirely... More »
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