Coral Reef Bleaching

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Abstract: Coral reef bleaching is caused by anthropogenic and natural variations in reef environment including warm sea surface temperature, solar irradiance, sedimentation, xenobiotics, subaerial exposure, inorganic nutrients, freshwater dilution, and epizootics.

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The study of sources of energy that replenish itself. Most sources of renewable energy are based on solar energy, either directly or via wind power, hydroelectric power, wave power and biomass (the products of photosynthesis). Geothermal power harnesses heat from deep in the ground or from tidal power.

The study of climate, the regular pattern of weather experienced in a particular place over a period of time. The primary factors affecting climatic variation are latitude, wind movements, ocean currents, the temperature difference between land and sea, and topography. Human activities have an increasing effect.

A mixture of particles that remain suspended in the air because they are so small that gravity has little effect on them. They fall naturally at about 10 cm (4 inches) a day, but are removed much more quickly by rain or snow. Aerosol particles include soil particles, salt crystals from the evaporation of sea spray, spores, bacteria and tiny insects.

Energy produced from renewable and supposedly ecologically safe sources, as opposed to nonrenewable sources with toxic by products that require special disposal, such as fossil fuels (in conventional power plants) and uranium (in nuclear power plants). Alternative energy source include flowing water, biomass (from the burning of crops grown, for fuel) waves and tides, wind, Sun and the heat in the Earth's crust.

A colourless gas, slightly soluble in water and denser than air. It is a waste product produced whenever carbon or substances containing carbon burn, and is also produced during respiration in plants, animals and microorganisms, and through the decay of organic matter.

The removal of solid rock particles from the land surface and their transport by water or wind. Agents of erosion include water (the sea, rivers), glaciers and wind. This is a natural and continual process that can be speeded up by human intervention.

Preserving energy resources by reducing the use of energy. Profligate and inefficient energy use by industrialised countries contributes greatly to atmospheric pollution and greenhouse effect, when it draws on nonrenewable energy sources.

An increase in the extent of the ice cover of a planet. Glaciation have punctuated Earth's history, the earliest having occurred during Proterozoic times. A glaciation may include both glacials and interglacials.

The gradual rising of the temperature of air in the lower atmosphere, believed to be due to the buildup of gases such as carbon dioxide, ozone, methane, nitrous oxide and chlorofluorocarbons. As the carbon dioxide component increases, as on Venus, most of the incoming solar radiation is trapped, with a rapid and unstoppable temperature rise.

The principle which requires that the costs of pollution whether incurred in preventing the release of a potential pollutant or in repairing pollution damage, should be internalised and met by whoever causes the pollution.

The previous epoch in geological time, at the beginning of the Quaternary period, about 2.5 million years ago. The Pleistocene ended about 10,000 years ago and was marked by extensive glaciations.

The variation in the atmospheric conditions experienced at a given site.

The mechanical and chemical processes that break up bedrock and reduce it to its individual bedrock or their derivatives.

The regular rise and fall of water levels in the world's oceans resulting from the gravitational attraction that is exerted upon the Earth by the Sun and the Moon.

A highly reactive pale blue gas - O3, with a penetrating odour. Ozone is an allotrope of oxygen, made up of three atoms of oxygen. At lower atmospheric levels ozone is an air pollutant and contributes to greenhouse effect. Near the ground, higher-than-usual concentrations of ozone can cause asthma attacks, stunted growth in plants and corrosion of certain materials.