Seven of the largest industrialized countries (Canada, France, Germany, Italy, Japan, UK, and USA) whose leaders meet regularly in economic summit meetings. …
A group that has replaced the Group of 7, by also including the European Union and Russia (which does not participate in all events). It holds an annual economic and political summit (the G8 Summit), comprising heads of government and international officials. …
1 A method of tree harvesting in which patches of selected trees are cut in order to create a mosaic of openings in the forest canopy and to encourage the growth of uneven‐aged stands. 2 A theory which explains altruistic behaviour in individuals in terms of benefits for the group. …
A small wood or group of trees that has no undergrowth. See also coppice. …
The period of the year during which temperature remains high enough to allow plant growth, which is usually between the average date of the last frost in spring and the first frost in autumn. Also known as cropping season . See also harvest. …
The annual growth pattern found in many organisms, such as snails. In coral the band is caused by the secretion of calcium carbonate. One yearly growth band contains two smaller bands, which represent winter growth and summer growth. …
The physical appearance and structure of an organism. …
The percentage rate at which something (such as an organism, population, or economy) is growing per unit time (normally a year). See also doubling time. …
The layer of wood growth that is formed by a tree during a single growing season, which includes both the earlywood (which forms in spring) and the latewood (which forms in autumn). Also known as annual ring . …
The process of growing a plant in order to produce fresh viable seed which can be used to evaluate the characteristics of its varieties. …
A narrow protective structure that is built out into the sea from the land, in order to restore an eroding beach by intercepting longshore drift and trapping sand. …
A group of species whose members exploit similar resources in a similar manner. …
A narrow, fast‐flowing warm ocean current which is part of the North Atlantic gyre. It starts in the Gulf of Mexico around the Caribbean, and (driven by the westerly winds and deflected by the Coriolis force) flows north‐eastwards across the Atlantic and warms the climate of the east coast of the USA. The current splits around the latitude of Spain and part of it flows south, heating the coast…
A deep ditch caused by the erosion of soil on a hillslope by running water. …
Glacial till that is highly weathered, has a high clay content, and becomes sticky and plastic when wet. …
The first period of glaciation in Europe during the Pleistoceneice age, equivalent to the Nebraskan in North America. …
A sudden, brief increase in wind speed, generally lasting less than 20 seconds. …
Any of the non‐flowering seed plants. Contrast angiosperm. …
An evaporite mineral that is formed by the evaporation of saltwater, and is used in making plasters and cements. …
A European moth ( Lymantria dispar ) that was introduced into North America in 1869 and is a serious defoliatingpest of hardwood shade trees. …
A permanent large‐scale circulation cell of water in the open ocean, which is driven by prevailing winds and the Coriolis effect. …
Freshwateranaerobic mud that contains abundant organic matter. …
The general growth pattern of a plant, which includes creeping plants, trees, shrubs, and vines. …
The place or set of environmental conditions (abiotic and biotic) in which a plant or animal normally lives. For a species to survive in a particular ecosystem, its habitat must support a population large enough to sustain itself by breeding. Habitats vary in size according to the species that occupy them. Carnivores usually occupy and require much larger habitats than herbivores, because a carniv…
A management plan that defines objectives and targets for the maintenance or enhancement of a particular habitat, and the actions that are regarded as necessary to achieve them. Also known as habitat conservation plan . …
The network of corridors that links isolated patches of habitat, which allows organisms to move through an area. See also fragmentation. …
Any managed change to a habitat that improves its value and increases its ability to meet the particular needs of one or more species. …
The break‐up of a large habitat into a number of separate, smaller remnants, for example because of land use change. See also corridor. …
Any physical attribute of the environment (such as soil pH or the salinity of a water body) that can be measured to characterize the conditions necessary to support an organism, population, or community in the absence of pollutants. …
The disappearance or conversion of natural habitat, often as a result of human actions. …
An area of habitat that differs from the surrounding area, and meets particular needs for particular organisms. …
Restoring a habitat to its original community structure, by removing exotic species and/or reintroducing native species. See also active restoration, natural process restoration. …
A major initiative of the European Union that is designed to protect biodiversity through the conservation of natural habitats and wild plants and animals, and the creation of a network of protected areas across the EU to be known as Natura 2000 sites. …
An area of land that is capable of supporting a particular climax plant association. …
A dust storm or sandstorm that is caused by cold downdrafts from a thunderstorm which turbulently lift dust and sand into the air. The term is mostly used in connection with the Sudan. …
The deepest part of the ocean, at depths greater than the abyssal zone or more than six kilometres, which includes the lower levels of ocean trenches. …
The oldest period of geological time, extending from the origin of the Earth about 4.5 billion years ago until the date of the oldest known rocks, about 3.9 billion years ago (the start of the Archaean). There are no rocks on Earth this old. …
An important cell in the general circulation of the atmosphere. Warm air rises in the tropics and it flows towards the poles, transporting heat energy, whereby the air cools and sinks at around 30? north and south. The air then moves back towards the equator as wind (trade winds). …
A protein that is found in the red blood cells of mammals and other animals that carries oxygen round the body. …
Solid precipitation that falls as ice particles from cumulonimbus clouds. Individual particles are called hailstones, and the storm is called a hailstorm. …
1 The time required for half of the atoms of a radionuclide to decay, which is specific to each nuclide. Radon‐222 has a very short half‐life of 3.82 days, so compared with radium‐226 (half‐life of 1622 years) or thorium‐232 (half‐life of 14 million years), radon gas disappears very quickly. 2 The time required for a pollutant to decrease in concentration by half. For example, the half…
The dominance of ocean salt in water. See also saline. …
A circle of light around the Sun or Moon that is caused by the refraction or reflection of light by the ice crystals in cirrus clouds. …
A compound that contains carbon and at least one halogen, and sometimes hydrogen. Chlorofluorocarbons (CFCs) are halocarbons. …
A layer in a body of water at which salinity and thus density change sharply. …
Any of a group of five chemically related, non‐metallic elements (bromine, fluorine, chlorine, iodine, and astatine) that can combine with metals to form salts or substitute for hydrogen in many organic compounds. …
A compound in which a halogen atom has been introduced, via a chemical reaction. …
A soil that contains a significant proportion of soluble salts. …
A synthetic halogenatedhydrocarbon compound that consists of bromine and other halogens (which could include fluorine and/or chlorine), is used as a fire extinguishing agent, and persists in the atmosphere for a long time. Halons are much more effective in terms of ozone destruction than CFCs. See also ozone depletion potential. …
A salt tolerant organism, which is specially adapted to live in areas of high salt concentration. See also extremophile. …
A plant that is adapted to grow in salty soil and air. …
A rural settlement that is smaller than a village and contains a few houses. …
A surface of stones (pebbles, gravel, or boulders) on a desert, that is formed by the washing or blowing away of the finer material. …
A traditional method of fishing, using a hooked line which is held down in the water with a weight and pulled up by hand or with pulleys. Also known a jigging . …
The site of a nuclear facility in south‐central Washington, USA which was established in 1943 (during World War II) as part of the Manhattan Project, to provide the plutonium necessary for the development of nuclear weapons. …
A former glacialtributary valley that enters a larger glacial valley above the floor of the larger valley, high up on the valley wall. Waterfalls (such as Bridal Veil Falls in Yosemite) are common features of hanging valleys. …
Having one set of chromosomes in the nucleus of each cell as in mosses and many protists and fungi. …
A board‐like building material that is made from wood fibre. …
An approach to economic development that relies on conventional sources of energy, including fossil fuels and nuclear energy, which create environmental problems including pollution and waste management. Contrast soft energy path. …
A freeze in which vegetation is killed and the ground surface is frozen solid. …
The fruit or nuts of trees such as oak, beech, and walnut. …
1 A measure of the amount of dissolved salts (particularly calcium carbonate) in alkaline water. 2 The degree of resistance of a mineral to scratching, which is usually measured on the Moh hardness scale. …
A hard, relatively impervious, layer of soil in the lower A‐horizon or in the B‐horizon. It is difficult for plant roots to penetrate and is caused by cementation of soil particles with organic matter or with materials such as clay or calcium carbonate. Also known as clay pan . See also impeded drainage, indurated, iron pan. …
Alkaline water that contains dissolved mineral salts (particularly calcium and magnesium bicarbonates), which reduces the cleansing power of soap and produces limescale in hot water appliances. See also ion exchange treatment. …
A dry desert wind that blows from the Sahara onto the coast of West Africa between November and March. …
A spear with a barbed point and a strong line attached to it, which is used for catching large fish (such as giant tuna and swordfish) or whales. …
Farm equipment that is used to break up clumps of soil on heavy ground. …
A technique that breaks up the soil in preparation for planting. Also known as disking . …
1 The act of gathering a ripened crop. 2 The season in which a crop is gathered. See also cropping season. 3 The yield from plants in a single growing season. See also crop yield. …
The removal of mature trees from a forest. Contrast intermediate cut. …
The gathering of a ripened crop or the felling and removal of trees. …
Relating to the mouthparts of an insect that are modified for sucking. …
Grass that has been mowed and dried for use as fodder. …
A field of grass which is cut two or three times in the summer to produce a crop of hay for feeding to livestock. …
A source of danger or disruption. See also natural hazard. …
The analysis and evaluation of the physical, chemical, and biological properties of a particular hazard. The term, as used in North America, is usually applied to human exposure to particular agents such as toxic substances. Also known as hazards analysis, evaluation . …
The process of determining whether exposure to a particular agent might affect human health. …
The sum of all hazard quotients for a specific pathway or scenario, which takes into account the presence of multiple substances at one site, or exposures to the same chemicals through multiple media and pathways. …
The process of establishing where and to what extent particular hazards are likely to pose a threat to people, property, and the environment. …
Any air pollutant that in the USA is not covered by ambient air quality standards but which (as defined in the Clean Air Act) may reasonably be expected to cause or contribute to irreversible illness or death. Examples include asbestos, mercury, radionuclides, and vinyl chloride. …
Any chemical whose presence or use is a physical hazard or a health hazard. Examples include flammables, explosives, and acids. …
Any substance that, because of its quantity, concentration, or physical, chemical, or infectious characteristics, has the potential to cause a physical or health hazard. Also known as hazardous material . …
Waste material that is reactive, toxic, corrosive, or otherwise poses a hazard to human health and the environment. Contrast toxic waste. …
A landfill site in which hazardous waste is deposited and covered. …
Reducing the amount of hazardous waste that is produced by a facility, via source reduction or environmentally‐sound recycling. …
A measure of the health risk of exposure to a particular toxic material, expressed as the ratio between average daily dose and a reference dose defined from toxicity tests. …
A method used in the USA by the Environmental Protection Agency for evaluating potential relative risks to public health and the environment from abandoned or uncontrolled hazardous waste sites. The scale runs from 0 to 100; if a site scores 28.5 or more it is placed on the National Priorities List. See also National Oil and Hazardous Substances Contingency Plan, Site Inspection. …
A reduction in visibility that is caused by fine dry particles of dust and pollutants. …
1 The source of water from which a stream arises. Also known as headwater . 2 The elevation of a water surface above a particular point, such as the height of water in a reservoir above the turbine that is used for generating hydroelectricity. 3 Unsorted angular rock debris. …
1 A rocky promontory that sticks out into the sea. 2 A strip of unploughed land at the end of a set of furrows or along a fence. …
A steep slope at the head of a valley, such as the rock cliff at the back of a cirque. …
The source and upper part of a stream. Also known as head . …
A state of complete physical, mental, and social well‐being and not merely the absence of disease or infirmity. …
The process of collecting, analysing, and disseminating information on health status and health risks, which is used in prioritizing and managing public health problems. …
A chemical, a mixture of chemicals, or a pathogen for which there is statistically significant evidence that acute or chronic effects may occur in any people who are exposed to it. …
An initiative from US President George Bush that is designed to improve regulatory processes to reduce the risk of catastrophic wildfires and restore forest health. …
A US non‐profit anti‐environmentalthink‐tank that was founded in Chicago, Illinois in 1984 and whose mission is to help build social movements in support of ideas that empower people. Such ideas include market‐based approaches to environmental protection, privatization of public services, and deregulation in areas where property rights and markets do a better job than government bureaucr…
The wood in the centre of a tree that is composed of non‐living cells and is usually darker than the sapwood. …
A form of energy that is transferred from one body to another (by conduction, convection, advection, and radiation) because of a difference in temperature, from regions of higher temperature to regions of lower temperature. …
The amount of heat energy that is required to to raise the average temperature of a mass, usually expressed in Joules per Kelvin (J K?1). See also British thermal unit, calorie, specific heat. …
Any engine that makes use of heat to do mechanical work. …
A mild form of heat stroke that causes faintness, dizziness, and heavy sweating in humans. …
The amount of heat that is transferred across a surface of given area in a given amount of time. Also known as thermal flux . …
A plant community that is dominated by low‐growing shrubs with woody stems and narrow leaves (members of the Ericaceae or heather family), which often grow on acidic or upland soils. …
A low shrub with small evergreen leaves and clusters of pink flowers, which was traditionally used in Britain to make brooms, thatch, and bedding, and for heating ovens. Also known as ling . …
Uncultivated land with heather and heath growing on acidic, nutrient‐poor, sandy soils. …
The apparent temperature that is created by the combined effect of high air temperatures and high humidity levels. …
The amount of heat energy that is required to change a substance from solid to liquid at constant temperature. Also known as heat of melting . See also latent heat. …
The amount of heat energy that is required to change a substance from liquid to gas at constant temperature. …
A condition that results from excessive exposure to intense heat, causing high fever, collapse, and sometimes convulsions or coma in humans. …
A continuous period of unusually and uncomfortably hot weather. …
A metallic element that has a high atomic weight, is often toxic, and tends to accumulate in the food chain. Examples include arsenic, cadmium, chromium, lead, and mercury. See also bioaccumulation. …
Water that contains deuterium, a heavy isotope of hydrogen, which is used in nuclear reactors to slow down neutrons. …
A nuclear fission reactor that uses deuterium‐enriched water to moderate the fission reaction. …
A unit of area that is equal to 10?000 square metres or 2.47 acres. …
A natural fence that is created by a row of closely planted shrubs or bushes. …
An untrimmed hedge or barrier of bushes, shrubs, or small trees that are growing close together in a line, which creates a natural growing fence and provides cover and a corridor for wildlife. See also live fence. …
A method of economic evaluation, based on the premise that the price of a good is partly determined by its characteristics or the services it provides. The approach seeks to value the individual characteristics of that good by studying how the price people are willing to pay for it changes when the characteristics change. It is widely used to explain variations in house prices in terms of variatio…
A helicopter equipped with a specially designed tank that is used for transporting and dropping suppressants or retardants on wildfires. …
A natural, inert gas that is colourless, non‐toxic, non‐combustible, and lighter than air. It is the second lightest and second most abundant element. Roughly 25% of the Sun is helium, but it accounts for only 0.0005% of the Earth's atmosphere. See also high temperature gas‐cooled reactor. …
Incomplete or partial metamorphosis in insects. Contrast holometabolism. …
A deep‐sea sediment that accumulates near the continental margin, and is composed of material that comes from both land and sea. …
Half of the Earth, defined either in terms of north and south of the equator, or east and west of the Greenwich Meridian. …
See human exceptionalism paradigm, hydroelectric power. …
Any small, non‐woody vascular plant, such as grass or forbs. …
Non‐woody vegetation that dies back each season. …
The vegetation in the understorey in a forest that consists mainly of non‐woody plants. Also known as ground cover . …
The edible biomass of herbaceous plant, on which grazing animals feed. …
1 A collection of dried, pressed, or preserved plant specimens (leaves, flowers, seeds, and stems). 2 The kitchen garden of an abbey or monastery. …
A chemical pesticide that is used to control or kill specific unwanted plants, particularly weeds. See also contact herbicide, systemic herbicide. …
An organism that eats only plants. Granivores and frugivores are special types of herbivores. See also primary consumer. …
1 A group of domesticated mammals (such as cattle or sheep) that are kept together and looked after by humans. 2 A group of wild animals of one species that remain together in a colony, such as antelope, elephants, seals, or whales. …
The passing on of characteristics from one generation to another, which in organisms takes place via genes. See also inherit. …
A measure of the extent to which a characteristic in an organism is related to genetic, inherited factors relative to the mean of the population. …
1 Anything that is inherited from an ancestor. 2 The overall natural and cultural inheritance of a country, including important natural or archaeological sites, historic buildings, customs, and traditions. …
A US non‐profit anti‐environmentalthink‐tank that was established in 1973 and whose mission is to promote conservative public policies based on the principles of free enterprise, limited government, individual freedom, traditional American values, and a strong national defence. …
An individual born with genitalia and/or secondary sexual characteristics which combine features of both sexes. For example, an earthworm. See also androgeny. …
Reptiles (such as snakes, turtles, and lizards) and amphibians (such as frogs, toads, and salamanders). …
An SI measure of frequency (number of cycles per second). …
Variety or diversity, lack of uniformity; the variety of qualities found in an environment (habitat patches) or a population (genotypic variation). Contrast homogeneity. …
An organism that is unable to synthesize organic compounds (and thus get its energy) from the environment, so it must feed upon organic compounds that are produced by other organisms. There are three types of heterotroph that derive energy from different sources, namely saprophytes, parasites, and holozoic organisms. Also known as consumer . Contrast autotroph. …
Having different alleles (forms) of a particular gene; genetic variability among individuals within a populations, and among populations. …
Secure places (such as caves or dens) where animals hibernate during the winter in order to conserve energy. …
A long‐term, deep sleep during which some animals' heartbeat and respiration rates slow down to allow them to survive the winter cold period when there is little food available. …
1 The skin of a large, mature animal. 2 A hut or tent that allows observers of wildlife to conceal themselves. …
A series of ordered groupings of things within a system. …
Woodland that is managed to allow the majority of trees to reach maturity. Contrast coppice. …
Towards the poles, away from the equator. Contrast low latitude. …
A passenger vehicle that carries more than a specified minimum number of passengers, such as a bus or a car used within a carpool. Contrast low occupancy vehicle. …
An area of high atmospheric pressure. Also known as anticyclone or high . …
A community of people which is located close to numerous potential environmental and health hazards, which may result in high levels of exposure to contaminants or pollutants. …
General term for international areas of the oceans that lie beyond the legal control of any nation. Similar to open sea. …
A nuclear fission reactor that uses helium gas to transfer heat from the core to a steam generator. …
High water. The highest level to which the tide rises within the daily tidal cycle. Contrast low tide. …
The maximum height or stage that is reached by rising water, such as a rising tide at the coast or a flood in a river. …
The line along the coast to which the sea rises at high tide. Contrast low water mark. …
Sustained winds of 40 miles per hour, mph (64 kilometres per hour, kmh) or greater which last for an hour or more, and/or gusts of greater than 58 mph (93 kmh). …
A variety of crop plant that produces a high yield relative to other varieties. See also Green Revolution. …
A method of harvestingnatural resources that removes the biggest and best of a species (for example of trees in a forest, or fish in the sea) and ignores the rest. …
A method of cable logging in which timber is dragged from where it is cut to a collecting point by a powered cable above ground level. Contrast ground‐lead logging. …
The longest‐lasting and most dangerous of all the radioactive waste produced by the nuclear industry, which contains highly radioactive, short‐lived fission products, hazardous chemicals, and toxicheavy metals. Contrast low‐level waste, intermediate‐level waste. …
A facility that is designed to handle the safe disposal of spent nuclear fuel, high‐level radioactive waste, and plutonium waste. …
A place where highly radioactive wastes can be buried and stored safely for tens of thousands of years, unexposed to groundwater and earthquakes. See also Yucca Mountain. …
A local, well‐defined elevated area of land with a rounded top, smaller than a mountain. See also hillslope. …
Farming in an upland environment, where the land is sloping, fields are often relatively small, soil erosion is a common problem, and yield is often relatively low because of harsh climate and poor soils. …
A type of dry prairie that is found in well‐drained sites at the tops of hills, bluffs, and ridges, and on steep slopes. …
The side or slope of a hill. Also known as hillside . See also colluvium. …
The area that is tributary to a place and linked to it by economic activities. …
1 Related to the known or recorded past, in times of written history. See also prehistoric. 2 Important or famous in history. …
A land zoning category in the USA that applies to an area in which the buildings have particular historic, architectural, or cultural significance. …
The natural ecosystem that currently exists or is known to have existed in the past, which guides restoration activities. …
The natural range or geographical areas that a particular species was known or believed to occupy in the past. …
The study of past events within the historic period. …
A wet, organic order of soil that is found in bogs, swamps, and wetlands, and contains a large amount (usually more than 30%) of organic material. …
See Protocol on Preparedness, Response and Co‐operation to Pollution Incidents by Hazardous and Noxious Substances (2000). …
A form of frost that consists of a deposit of needle‐like soft ice crystals formed on vegetation, the ground, or window‐panes by direct condensation from the air at temperatures below freezing point. Also known as white frost . …
A pond or reservoir that is usually made of soil or sediment, and is designed to store pollutedrunoff. …
A container where wastewater is stored before it is removed for treatment or disposal. …
The maximum amount of time that a sample (for example, of soil or polluted water) can be stored before analysis. …
The idea that the whole is greater than the sum of the parts, so that studying a whole system and its interrelationships is better than studying isolated parts of it. Contrast reductionism. …
An explanation that attempts to explain complex phenomena in terms of the properties of the system as a whole. See also holism. …
A holistic approach to the management of natural resources, that takes into account interrelationships between people, the environment, and ecosystems. …
The post‐glacial epoch. The most recent phase of geological time within the Quaternary, which began 10?000 years ago, after the end of the Pleistocene ice age when glaciers retreated and sea level rose because of a warmer global climate. Climatic change in the northern hemisphere through the Holocene includes the Climatic Optimum, the Medieval Warm Period, and the Little Ice Age. …
Complete metamorphosis in insects. Contrast hemimetabolism. …
Marineorganisms that spend all their life in water and not on or in the sea bed. …
A heterotrophicorganism that ingests complex organic matter, and can absorb large particles of undissolved food and soluble compounds. All higher animals (including humans) are holozoic. …
The process of self‐regulation which maintains steady state within environmental systems through adjustment and feedback. …
A warm‐blooded organism (such as a bird or mammal) that regulates its body temperature independently of changes in the temperature of its environment. Contrast ectotherm, poikilotherm. See also endotherm. …
An area in which an animal normally lives, and from which it gets its food. Contrast territory. …
The home and adjacent land that is occupied by a family. …
A primate of the family Hominidae, which includes Homo sapiens as well as extinct human ancestors. …
Modern humans and their extinct immediate ancestors. Erect, bipedal (walk on two feet) primates with relatively large brains. …
A view of nature that only considers human, rather than plant or animal, needs. Contrast ecocentric. See also anthropocentric. …
Induced colour change in an organism based on perception of the background against which they are cultured. …
A species of hominid that lived between 1.8 million and 300?000 years ago, stood upright, had a brain slightly smaller than that of modern humans, and was the first Homo species to migrate beyond Africa. …
A species of hominid that lived in East Africa between 1.9 and 1.8 million years ago. Homo habilis was the first hominid to make and use tools. …
A species of hominid that lived between 150?000 and 30?000 years ago (the Middle Palaeolithic) in Europe and Western Asia. Once thought to be a geographical variant of Homo sapiens it is now regarded as a distinct species. …
Modern humans who appeared in the fossil record about 200?000 years ago. …
The lower part of the Earth's atmosphere, consisting of the troposphere, stratosphere, and mesosphere. …
The physical principle that the stress within a solid is proportional to the strain, so that the movement of an object is proportional to the pressure that is applied to it. …
A method of small‐scale fishing in which fish are caught in a net that is suspended from a hoop on a pole. …
1 The line where the visible edge of the Earth's surface meets the sky. 2 A surface that separates two adjacent beds in sedimentary rocks. 3 See soil horizon. …
A chemical substance that is produced in the body by an endocrine gland, is carried around the body in the bloodstream, and regulates the activity of other organs or cells in particular ways. …
A sharp‐edged mountain peak (such as the Matterhorn) that is formed by glacial erosion when cirques erode simultaneously on more than two sides of a mountain. See also ar?te. …
The subtropical region at latitudes 30? to 35?, where winds are mainly light and the weather is hot, dry, and settled. …
An upstanding block of the Earth's crust that is bounded by faults and has been uplifted by tectonic forces. Also known as fault‐block mountain . …
The cultivation of plants, particularly fruit, flowers, ornamental plants and vegetables, usually for sale, either in gardens and smallholdings or on general farms. …
An animal or plant that supports a parasite, although the host does not benefit and is often harmed by the association. …
The country where the reduction, avoidance or sequestration of greenhouse gasemissions takes place. …
The extent to which a herbivore feeds on a host plant when it is offered a choice of host plants, either simultaneously or sequentially. …
In the context of climate change negotiations, a broad term for reductions in greenhouse gas emissions (for example, in the former Soviet Union) that are caused by economic crisis rather than intentional efforts to reduce emissions. …
A desert (such as the Sahara in North Africa) that is located between about 20? and 30? north and south of the equator, where evaporation rates exceed precipitation and temperatures can be very high. Desert surfaces heat up rapidly during the day in the scorching sun (daytime temperatures of up to 55?C in the shade are not uncommon) and lose heat rapidly at night by radiation back to the overlying…
An approach to the exploitation of geothermal energy, in which cold water is pumped through fractured hot dry rock deep underground, is heated by contact with the rock, and is then extracted and used for heating and electricity generation. …
An area of the Earth's crust where there is molten igneous rock close to the surface, which provides a source of geothermal energy. …
An area that has an unusually high level of some particular quality or activity, such as air pollution, biodiversity, or volcanic activity. See also biodiversity hotspot. …
