132 of the Geography glossary’s terms, each with the part of the syllabus where you first meet it.
The process by which marine organisms such as corals, molluscs and some plankton build shells and skeletons of calcium carbonate from dissolved calcium and carbonate ions.
A carbon trading system in which a government sets a declining cap on total emissions, issues allowances up to that cap, and lets firms buy and sell them.
A view of development, associated with Amartya Sen, that judges progress by people’s real freedoms to be and do what they value, rather than by income alone.
The total amount of load that a river can carry at a given discharge.
The ability of people, organisations and systems to use their resources and skills to manage a hazard event and its effects.
The upward movement of water through narrow spaces between soil particles, against gravity, which can carry dissolved salts towards the surface.
The harvesting of wild fish and other aquatic animals from the sea, rivers and lakes, as opposed to farming them.
A residential area designed so that most households do not own or need a car, with streets reserved for walking, cycling and access, and any parking placed at the edge.
Technology that captures CO₂ from large sources such as power stations and industrial plants, transports it and stores it permanently in underground rock formations.
The increase in plant growth and water-use efficiency caused by higher carbon dioxide concentrations in the air, strongest in C3 plants such as wheat and rice.
Methods that remove CO₂ from the atmosphere and store it in plants, soils, rocks or the ocean, such as afforestation, direct air capture and enhanced weathering.
The total greenhouse gas emissions, in tonnes of CO₂-equivalent, caused directly and indirectly by a person, organisation, event or product over a period or over its life cycle.
Compensating for greenhouse gas emissions by paying for an equivalent reduction or removal elsewhere, usually by buying carbon credits from projects such as forest protection.
A carbon store that absorbs more carbon from the atmosphere than it releases, reducing the concentration of carbon dioxide in the air; the oceans and growing forests are the main natural sinks.
A reservoir in the Earth system that holds carbon for a period of time, such as the atmosphere, oceans, vegetation, soils, permafrost, fossil fuels and sedimentary rocks.
A tax on the carbon content of fuels or on greenhouse gas emissions, which raises the cost of polluting activities and gives an incentive to cut emissions.
A market-based approach in which permits to emit greenhouse gases are bought and sold, so that emissions are cut where it is cheapest to do so; also called emissions trading.
The maximum population that an area can support indefinitely with its available resources without degrading the environment; for people it depends on technology, trade and levels of consumption.
A chain of hazards in which one event triggers others, such as an earthquake causing landslides, liquefaction and a tsunami, or an eruption followed by lahars.
The proportion of people diagnosed with a disease who die from it, usually expressed as a percentage.
A located, detailed and recent study of one place, event or issue, with data on causes, impacts and responses, used as evidence for discussion in an answer.
A payment of money from a government or aid agency directly to poor or vulnerable households, given either unconditionally or on conditions such as school attendance or clinic visits.
A bond sold to investors that pays a government or insurer a set sum if a defined disaster, such as an earthquake above a given magnitude in a given area, occurs; otherwise investors keep their money and interest.
The suppression or control of speech, writing, media or online content by a government or other authority that considers it harmful, offensive or a threat to security or public order.
The commercial centre of a city, with the highest land values and accessibility, tall buildings, a concentration of offices, shops and services, and few residents.
Christaller's model (1933) of the size, number and spacing of settlements that serve their surrounding areas, in which higher-order centres with larger ranges and thresholds are fewer and further apart.
An irrigation system in which a line of sprinklers mounted on wheeled towers rotates around a central water supply, watering a circular field.
The movement of people or economic activity away from the centre of an urban area, such as suburbanisation and counter-urbanisation.
The movement of people or economic activity towards the centre of an urban area, such as rural–urban migration, gentrification and reurbanisation.
Migration in which people follow relatives, friends or neighbours who have already moved, relying on them for information, housing and work at the destination.
The modification of a river channel by straightening, deepening, widening or lining it, usually to carry floodwater away more quickly; also called channel modification.
The idea, proposed by Jule Charney in 1975, that vegetation loss in drylands raises surface albedo and reduces rainfall, so that less vegetation grows: a positive feedback.
A small, low barrier built across a stream or gully to slow runoff, trap sediment and let water infiltrate and recharge groundwater; the johad of north India is one form.
The decomposition of rock by chemical reactions that change its minerals, such as hydration, oxidation and solution; it needs water and is fastest in warm, wet climates.
A statistical test comparing observed frequencies in categories with the frequencies expected if there were no difference or association, to see whether the gap is significant.
A narrow, strategic passage on a transport route, such as a strait or canal, through which a large share of trade passes and where disruption would block or delay supply.
An acute diarrhoeal disease caused by the bacterium Vibrio cholerae, spread through food or water contaminated with faeces, which can kill through dehydration within hours.
A map that shades areas such as countries or districts in graded tones of one colour according to classes of a value expressed as a rate or ratio, such as density or a percentage.
A slow-moving, long-term pressure that weakens a city over time, such as poverty, inequality, ageing infrastructure, water scarcity or sea-level rise.
A small, steep volcanic cone built from loose fragments of tephra, usually during a single short-lived eruption.
An economic system that designs out waste and pollution, keeps products and materials in use at their highest value through reuse, repair, remanufacture and recycling, and regenerates natural systems.
An urban metabolism in which outputs such as waste, wastewater and heat are reused or recycled as inputs, so the city uses fewer resources and produces less waste.
An armchair-shaped hollow on a mountainside with a steep backwall, an over-deepened rock basin and a lip, eroded by a small glacier; it often holds a tarn after the ice melts.
The reporting of news, images and video by members of the public rather than professional journalists, usually shared through social media.
Scientific research in which members of the public collect, process or analyse data, usually following a standard method designed with professional scientists.
The citizens, groups and organisations that act collectively outside government and business, such as NGOs, community groups, faith groups, trade unions and social movements.
An organisation formed by citizens outside government and business to pursue shared interests or values, such as a charity, campaign group or trade union; an international one works across several countries.
A model of sector shift in which, as an economy develops, employment moves from the primary sector to the secondary sector and then to the tertiary and quaternary sectors.
The use of measures such as regrading, drainage, toe protection, rock bolts and vegetation to reduce erosion and mass movement on a cliff.
The view that climate change is an ethical and political issue because those least responsible for emissions are often most vulnerable to its effects, so the costs of responding should be shared fairly.
A computer simulation of the climate system, based on the physics of the atmosphere, oceans, land and ice, used to project future climate under different scenarios of greenhouse gas emissions.
The planned, permanent movement of a community away from a place made unsafe or uninhabitable by the effects of climate change, such as erosion or permafrost thaw.
A plausible, internally consistent description of how the climate might develop under particular assumptions about emissions and socio-economic change, such as the IPCC’s Shared Socioeconomic Pathways; not a prediction.
A theory that live, round-the-clock television and online news coverage of a crisis influences governments’ decisions, for example by creating public pressure to send aid.
The planning and use of strategies to reduce coastal erosion and flood risk and to balance the competing human and environmental uses of a coastline.
The division of a coastline and its waters into zones in which particular uses, such as ports, tourism or conservation, are permitted or banned.
A measure of relative variability equal to the standard deviation of a set of values divided by their mean, multiplied by 100; for annual rainfall, a higher percentage means less reliable rain.
An ocean current colder than the surrounding water and air, usually flowing from high latitudes towards the Equator on the eastern side of an ocean basin.
A glacier whose base is below the pressure melting point and frozen to the bedrock, so it moves only slowly by internal deformation and does little erosion.
A word or phrase at the start of an examination question, such as describe, explain or evaluate, that states what kind of answer is wanted and how much depth it needs.
Farming in which crops or livestock are produced mainly for sale, with the aim of making a profit.
The process by which cultural traditions, objects, places or experiences are turned into products to be bought and sold, often for visitors.
The principle that certain areas and their resources, such as the deep seabed beyond national jurisdiction, belong to all humanity and must be managed for the benefit of all.
A customs union in which goods, services, capital and people can also move freely between member states.
A resource, such as an aquifer or fishery, from which it is difficult to exclude users and where each user's consumption reduces what is left for others.
An illness caused by a pathogen such as a bacterium, virus or parasite that can pass between people or animals, directly or through water, food, air or a vector.
A member of a community, given basic training, who provides health education, preventive care, simple treatment and referrals in that community, often where doctors are scarce.
The involvement of local water users in decisions about the planning, construction, operation, maintenance and financing of water services and resources.
An approach in which local people identify the hazards they face and plan, carry out and monitor their own risk reduction actions, often with support from governments and NGOs.
Tourism that is owned and managed by a local community, which decides how visitors are received and keeps most of the income.
A system in which consumers pay a farm in advance for a share of its produce for the season, so that consumers and the farmer share the risks and rewards of production.
A town or village, usually beyond the edge of a city, whose residents mostly travel to work in the city each day.
An urban form with relatively high residential density and mixed land uses, which reduces travel distances and the amount of land built on.
The size of the largest particle that a river can transport at a given velocity.
A steep-sided cone built from alternating layers of ash and lava erupted from viscous magma, often explosively, such as Mount Fuji.
A bar graph in which each bar is divided into parts showing the components of a total, either as values or as percentages of 100.
A technology in which mirrors focus sunlight onto a receiver to heat a fluid that drives a turbine; the heat can be stored, for example in molten salt, to generate power after dark.
A coastline where bands of rock of different resistance run parallel to the shore, so that a resistant outer band protects weaker rock behind it.
The policy conditions, such as spending cuts, tax rises or privatisation, that a borrowing country must accept in order to receive a loan from the IMF or another lender.
The funnel-shaped lowering of the water table around a well that pumps groundwater faster than it can flow in from the surrounding aquifer.
A grid that compares each pair of land uses or activities in an area and shows whether they are compatible, in conflict, or compatible only under certain conditions.
A low, long and gentle wave, breaking about 6–8 times a minute, whose strong swash and weak backwash move sediment up the beach and build it up.
The use of a place's scenery, heritage or atmosphere as a product that visitors experience and pay for, which can change or degrade the landscape being consumed.
The emissions caused by the goods and services consumed in a country, wherever they were produced: territorial (production-based) emissions minus emissions in exports plus emissions in imports.
Expansion diffusion through direct contact between people or neighbouring places, so that spread is strongly affected by distance from the hearth.
The transport of goods in standard-sized steel containers that can be moved between ships, trains and lorries without unpacking, which cut shipping costs and required large new port terminals.
A situation in which different stakeholders compete for the same urban land or disagree over how it should be used or changed, usually because they gain or lose differently from the change.
The belt of sea from 12 to 24 nautical miles from a state's baseline, in which the state may enforce its customs, tax, immigration and health laws.
The thick, less dense layer of mainly granitic rock, about 25–70 km thick, that forms the continents; it is too buoyant to subduct and parts are about 4 billion years old.
In law, the seabed and subsoil beyond a state's territorial sea to 200 nautical miles, or to the edge of the continental margin up to 350 nautical miles, over whose resources the state has rights.
The effect of distance from the sea on climate: places deep inside a large continent have a larger annual temperature range and usually less precipitation than coastal places at the same latitude.
Permafrost that underlies 90–100% of the ground surface, found where mean annual temperatures are well below freezing; it is often hundreds of metres thick.
A line on a map joining points of equal height above sea level; the vertical distance between adjacent contours is the contour interval.
An arrangement in which a buyer, usually a company, agrees in advance to purchase a farmer’s produce at an agreed price, quantity and quality, often supplying inputs and advice in return.
A circulation in which hot, less dense material rises, spreads and cools, then sinks again; in the mantle it transfers heat outward over millions of years.
A plate boundary where two plates move towards each other, so that one plate subducts or the crust is crumpled in a collision.
A roof with a light-coloured or reflective surface of high albedo, so that it absorbs less solar radiation and stays cooler than a conventional dark roof.
The whitening of corals when unusually warm water makes them expel the algae living in their tissues that supply most of their food; if the heat lasts, the corals die.
A structure built over thousands of years from the calcium carbonate skeletons of reef-building corals, in warm, shallow, clear tropical seas, supporting very high biodiversity.
A region with a concentration of people, economic activity, investment and political power, usually centred on a capital city, port or industrial area.
A spatial pattern in which a dominant core region, holding most of a country’s wealth, investment and power, is surrounded by less developed peripheral regions that depend on it.
The apparent deflection of moving air and water caused by the Earth’s rotation, to the right in the northern hemisphere and to the left in the southern hemisphere; zero at the Equator.
Describing the optimistic view that human ingenuity, technology and markets will always find ways to overcome resource shortages, so population and economic growth can continue.
A relationship between two variables in which one changes as the other changes: positive when both rise together, negative when one rises as the other falls.
A method of appraising a project by comparing its expected costs and benefits, usually in monetary terms over its lifetime, to judge whether it is worthwhile.
The net movement of people from large urban areas to smaller towns, villages and rural areas beyond the edge of the city.
Products made and sold with a copied trademark or design so that they appear to be genuine branded goods, in breach of intellectual property law.
An international initiative led by Gavi, CEPI and the WHO, with UNICEF, to buy and distribute COVID-19 vaccines fairly to all countries, especially low- and middle-income countries.
A small area in which crime occurs much more frequently than in the surrounding area, identified by mapping recorded crimes.
An approach that reduces opportunities for crime by designing buildings and public spaces with natural surveillance, clear boundaries, good lighting and maintenance.
The lowest mean velocity at which a particle of a given size is picked up and set in motion by flowing water; also called the entrainment velocity.
The systems and assets, such as energy, water, transport, telecommunications and health services, that are essential to a city’s functioning and whose loss would cause severe disruption.
The value from a statistical table that a calculated test statistic must reach for the result to be significant at a chosen level, for a given sample size or degrees of freedom.
A side view of the shape of the land surface along a straight line between two points, drawn from contour heights on a map or from field measurements.
Obtaining information, ideas, services or funds from a large number of people, usually through the internet or mobile phones, rather than from employees or official sources.
Raising money for a project, cause or person by collecting small contributions from a large number of people, usually through an online platform.
Mapping in which many volunteers add data, such as roads, buildings or damage seen on satellite images or reported by phone, to a shared online map used by responders.
The parts of the Earth’s surface where water is frozen, including ice sheets, glaciers, sea ice, lake and river ice, snow cover and permafrost.
The spread of cultural traits, ideas and products from their place of origin to other places and peoples, through migration, trade, media, tourism and the internet.
The variety of cultures, languages, ethnicities and identities found in a place, from the local to the global scale.
The creation of new cultural forms, such as foods, music, languages or festivals, by mixing traits from two or more cultures.
The spread and dominance of one society’s culture, products and values over others, through economic and political power, so that local cultures are weakened or replaced.
A landscape shaped by the people who live in it, whose buildings, land uses, signs and sacred sites show their culture and how it changes.
A single element of a culture, such as a language, a religious practice, a food, a style of dress, a type of music or a custom.
The shared beliefs, values, customs, practices, language and material goods of a group of people, learned and passed on from one generation to the next.
A process in which an initial advantage attracts investment and growth, which create further advantages and growth, so success builds on itself in an upward spiral.
Rights to own or use land that come from the traditions of a community, such as a village, clan or herding group, rather than from a title registered by the state.
A free trade area whose members also set a common external tariff on imports from non-member countries.
Crime carried out using computers and the internet, either by attacking computer systems and data or by using digital networks to commit offences such as fraud, theft and extortion.
The protection of computer networks, devices, programs and data from attack, damage or unauthorised access, through technology, procedures, training and cooperation between organisations and states.
A self-reinforcing sequence in which low income leads to poor housing, diet, health and education, which lead to low-paid work or unemployment, keeping income low and passing disadvantage to the next generation.