Geography Dictionary

Calcareous soils – soils controlled by a calcium-based parent-material such as limestone or chalk.

Calcification – deposition of calcium carbonate in a soil in low precipitation areas having high rates of evaporation and thus water deficit.

Calcium carbonate – a compound with the formula CaCO₃.

Caldera – a volcanic cone where the original top and centre have been removed either through a massive eruption or through collapse leaving the base of the cone as a large ring-shaped ridge.

Calorie intake – a measure of the amount of energy derived from food. Requirements vary with sex, age, size and environmental factors. One of the measures having a bearing on health.

Calving – a form of ablation whereby a mass of ice breaks away from a glacier or sheet. After reaching a body of water the tip of the glacial mass is floated creating stresses with the main body remaining on land that cause it to snap free and float away as an ice-berg.

Cambrian – in geologic time, a period lasting from 570m to 505m years ago.

Canopy – when the trees in a woodland or forest area are close enough together that the upper leaf layer of the trees form a more or less consistent cover.

Canyon – a large-scale, steep-sided valley which is deeper than it is wide.

CAP – see common agricultural policy.

Capillary action – the upward movement of water through a channels in a substance. In geography, most commonly the upward movement of water through a soil. Caused by adhesion of the water to the channel surface and cohesion of water molecules to one another.

Capillary water – the water that moves around the soil and is available for plant use.

Capital – three forms can be identified:

• money capital is the finance to start or expand a business that comes either from shareholders or from loans.
• fixed capital is the investment of existing buildings or equipment to a business
• social capital is the social amenity infrastructure of an area that may attract a business to set up there.

Capitalism – a social and economic system relying on market mechanisms to allocate factors of production which are privately rather than state owned.

Carbonation – a form of chemical weathering where natural rainwater, a weak carbonic acid, reacts with calcium carbonate in rock to produce calcium bicarbonate.

Carbon dating – a means of dating organic material based on the fact that carbon-14, a radioactive component of all living things, decays at a known rate over time from death.

Carbon dioxide (CO₂) – an atmospheric gas which has in modern times made up approximately 0.03% of the atmosphere by volume. It is vital for photosynthesis and for its contribution to the Greenhouse Effect which allows life to exist on earth by absorbing long-wave radiation from the earth’s surface and holding the energy in what we know as air temperature.

Carboniferous limestone – a sedimentary rock laid down in the geological period 280-345 million years BP (the Carboniferous period). Has a calcium carbonate content of at least 80% meaning it was laid down in highly productive, warm, shallow seas which provided the necessary skeletal remains. Characterized by thick, well-jointed beds which are pervious and allow rapid carbonation leading to karst scenery.

Carbon monoxide (CO) – a gas produced through inefficient and therefore incomplete combustion of fossil fuels.

Carbon tax – taxes levied on fossil fuel products as a disincentive to consume them as a strategy to slow global warming.

Cardinal points – North, South, East, West.

Carnivore – an animal that consumes other animals for food.

Carrying capacity – the idea that any given environment can only support a finite population. Originating in ecology for plant communities, social geographers have tried to apply the idea to human populations.

Cartel – a group of producers within a single industry who agree to limit supply to keep prices high. To be effective they must control most of the productive capacity of the industry and every member must abide by the agreement. Not appropriate to all industries. Most countries legislate against cartels as they exploit the consumer to too great a degree. One famous, and legal, cartel is OPEC.

Cartography – map and chart making.

Cash cropping – the growing of crops for sale as opposed to consumption.

Catastrophism – the belief that landscape is the result of sudden, catastrophic events, rather than slow, day-to-day processes. Outmoded, but recognized as a contributory factor.

Catchment area – the area of land from which precipitation makes its way to a particular river channel.

Catena – sequence of soils on a slope where the differences between them are a direct function of the change in slope.

Cation exchange capacity – ability of the soil to retain cations and thus be fertile.

Cave – a recess in the ground.

Cavern – a large cave.

Cavitation – creation of pot holes in a stream bed due to the blasting effect of particles thrown against it by the formation and collapse of air bubbles. The bubbles form in streams flowing at high speed or under high pressure.

CBD – see central business district

Census – the collection of data about a population. At its simplest, a count of the number of people in an area. EMDC governments collect much more data to do with demographics, housing, social patterns and economic factors. These are usually carried out every ten years and participation is compulsory.

Central business district – a centrally-located (in space and/or time) zone of an urban area, containing the principal commercial, professional, retail and governmental functions.

Centrally planned economy – see command economy.

Central place theory – the idea that all settlements influence the area surrounding them in the provision of goods and services – the sphere of influence. This leads to a regular spacing of settlements of a similar size and function across a landscape. Larger settlements’ spheres of influence overlay those of smaller ones.

CFC – see chloroflurocarbon

Chalk – a porous, sedimentary rock formed mostly from the skeletal remains of marine organisms. Bedding planes and joints increase the permeability. It is relatively soft but, when uplifted, can maintain an upland landscape as the permeability allows the rapid removal of water which slows weathering and erosional degradation.

Channel efficiency – the ability of the channel to conserve energy that may otherwise be lost to friction. Measured by hydraulic radius.

Channel flow – run off of surface water in a defined channel as in a river or stream.

Channel morphology – shape and dimensions of the cross-section of a channel.

Chaparral – a biome of scrub vegetation i.e. one dominated by short, woody dense bushes, found in California. Related to maquis of the Mediterranean. Adapted for hot, dry summers and mild winters which may include periods of drought.

Chelation – a form of chemical weathering. Organic acids released during decomposition release iron and aluminium from the A horizon and combine with them to form chelates.

Chemical weathering – a weathering process in which the resultant material is chemically different to the original rock. Usually carried out by dilute acids. Rates will therefore increase with the increased presence of water and increased temperature except for carbonation in which weathering rates increase at lower temperature. Other types include hydration, hydrolysis and oxidation.

Chernozem – soil type often found in continental interiors with a temperate grassland biome type. Thick grass provides for rich black humus which is extended into the A horizon by fauna during warm summers. Wet spring and early summer leads to leaching. Hot late summer causes capillary action. Up and down movement of water leads to formation of calcium carbonate nodules at about 1m depth.

Chinook – the N. American name for a warm dry wind sinking on the leeward side of a mountain range. See Fφhn.

Chi-squared test – the comparison of an actual distribution of points with a random distribution of the same number of points to establish whether or not there is a significant enough difference to say that the actual distribution has occurred for a particular reason.

Χ²=Σ(O-E)²

                                                                                                                 E

            where O is the observed frequency and E is the expected frequency.

Chloroflurocarbons – chemicals which were used in foam, refrigeration units, and aerosols for many years. Their release into the atmosphere was held responsible for the depletion of helpful ozone in the stratosphere and they also act as a greenhouse gas. Many countries have now banned their use.

Choropleth map – a map using different densities of shading to indicate the distribution of different classes of data by administrative unit across an area.

Christaller, Walter – one of the main architects of central place theory.

Cirque – see corrie

City Action team – group of civil servants charged by 1980s and 1990s UK government with formulating solutions to inner city decay, particularly problems of unemployment and derelict land.

Clapotis – phenomenon where pattern of incoming sea waves exactly matches waves reflected by a sea wall or a sea cliff resulting in a static pattern of crests and troughs just offshore.

Clarke-Fisher model - theoretical change in the relative importance of primary, secondary, tertiary and quaternary employment sectors over time as an economy develops from pre-industrial, through industrial to post-industrial stages.

Clay – a particle size classification for rock. Clay should be a rock particle with a diameter of less than 0.002mm.

Clay-humus complex – a soil particle made up of clay and some humus.

Clean Air Act, 1956 – UK legislation to control the amount of smoke produced in urban areas in response to the smog that commonly afflicted them, often for days on end.

Cleavage – the line of weakness in a rock along which it will break when put under stress.

Cliff – a tall, vertical, or near vertical, rock face.

Climate – aggregate weather conditions of an area over a long period of time which allow for the designation of seasonal patterns and expected future weather.

Climate change – long term variations in climate, particularly related to average annual temperatures and annual rainfall.

Climax community - The stage in community succession where the community has become relatively stable through successful adjustment to its environment.

Climax vegetation – the dominant and stable vegetation combination achieved naturally under particular environmental conditions over a long period of time.

Clint – flat-topped block that forms the ‘paving stone’ in a limestone pavement.

Clouds – visible masses of water droplets and/or ice crystals formed by condensation in the atmosphere.

Cloud seeding – attempt to create or grow clouds by the introduction of condensation nuclei in order to cause greater precipitation.

Coast – a zone of interaction of the land and the sea at the margins where the two meet.

Coastal landforms – those landforms unique to erosional and depositional processes at coasts, or due to sea level changes.

Coastal management – the attempt to mitigate the effects of erosion and flooding in coastal areas. May be hard engineering – structural features that directly block water action such as sea walls – or soft engineering – giving nature a helping hand such as beach nourishment. Some modern approaches suggest humans should intervene less in coastal environments and advocate restricted development here thus allowing coastal retreat if it happens.

Col – a saddle-like landform between mountain peaks where two corrie glaciers have back-eroded an arκte.

Cold desert – in high latitudes where temperatures are very low, there may be very arid areas due to a lack of precipitation and/or the locking of water as ice.

Cold front – the boundary between a warm and a cold air mass where the cold mass is undercutting the warm, causing the latter to rise. The rate of rise tends to be rapid causing rapid cooling and condensation which leads to the formation of tall cumulonimbus clouds and short, heavy thunderstorms.

Cold glacier – one in which ice temperature remains very low (often -30˚C) all year. The glacier will not move very rapidly if at all and so erosion is minimal.

Collective farming – an agricultural system, commonly practiced in communist countries, in which land is leased by the government to a ‘collective’ of workers who operate the farm and, in theory, share its profits. The system was usually inefficient and often corrupted by further government intervention. In the USSR, the collective farm, or kolkhoz, was gradually phased out after World War 2 and replaced by the state farm, or sovkhoz.

Colonialism – the establishment of direct rule by one country over another, separate country, fundamentally to improve and protect the economic situation of the dominant power.

Colonizer plants – the first plants to establish themselves in a virgin environment as the pioneer community.

Command economy – an economic system in which all decisions are made centrally by the national government, usually through the establishment of sequential five-year plans. Their express purpose is to attain fair distribution of resources among all citizens, but they are often plagued by political and economic inefficiency and corruption and many have collapsed.

Commercial farming – food production for market sale. Farmer has economic aims such as profit maximization.

Comminution – the reduction in size of particles through attrition.

Common Agricultural Policy (CAP) – the system of organization of farming in the European Union (EU). http://europa.eu/pol/agr/index_en.htm

Communication – the movement and/or exchange of information, goods and people over time and space.

Community forests – a UK policy begun in 1990 to improve derelict areas on the edge of urban areas. Landowners are given help to plant woodland on land that has fallen into disuse which is then made accessible to the local community. Aims are to improve opportunities for recreation, education and wildlife.

Commuter – a person undertaking commuting.

Commuter village – a village near to an urban area where former residents of the urban area have moved to while retaining their original jobs. As the proportion of commuters in the village increases, its character will change and there may be a decline in services as the newcomers prefer to use services in the urban area.

Commuting – movement of people between place of residence and place of work and vice versa. Can vary over space (rural-urban, intra-urban and urban-urban) and time (daily or weekly).

Comparative advantage – the idea that areas tend to be more efficient in certain economic activities than others and so should specialise in them in order to maximize their quality of life through trade.

Comparison goods – those goods which are highly priced and which are bought infrequently. Purchase decisions are usually made after comparing different brands or models etc.

Competence – in rivers, the maximum particle diameter that can be carried at a given velocity.

Competition – where more than one company provides a good or service. Can keep prices low as competitors fight for customers by undercutting their rivals. However, this could put operators out of business and reduce competition, possibly causing price increases. Can also lead to inefficiency through duplication, especially in services.

Composite volcano – one in which the cone is made up of alternating layers of lavas and ashes.

Compressing flow – in a glacier, when gradient is reduced and the ice becomes thicker and slower.

Concentric-ring model – a theory of how urban land use develops over time. Developed by Earnest Burgess in 1924 to explain social patterns in Chicago, it was later proposed as a general theory of urban land use. It says that zones of transition, low, medium and high-class residences are found in concentric rings outwards from the CBD. Since discredited as having few real-life applications due to unrealistic base assumptions that fail to account for factors such as transport routes and topography.

Condensation – the formation of water droplets or ice crystals from water vapour when it is cooled to the dew point.

Conduction – the transmission of heat through a substance i.e. through touch from a higher temperature area to one of lower temperature.

Conditional instability – when the ELR is lower than the DALR but higher than the SALR then an air mass will initially be stable and may sink. However, if the rising mechanism takes the air mass to its dew point and beyond at the SALR then the air can become instable and rise of its own accord through the release of latent heat.

Confidence level – the degree of confidence that a statistical result is the correct one rather than one produced by chance.

Confluence – where two river channels join.

Conglomerate – in physical geography, a sedimentary rock in which smooth, rounded rock pieces have been cemented into silts and clays.

Coniferous woodland – woodland or forest made up of softwood trees having common characteristics such as an evergreen appearance, waxy needle-like leaves and usually producing seeds within cones which open to allow dispersal by wind.

Connectivity – the extent to which points, or nodes, in a network may be interconnected and thus a measure of the network’s efficiency in allowing transfers in space or time. See alpha index, beta index, cyclomatic number, detour index and gamma index for measuring methods.

Consequent stream – a stream created as a consequence of uplift.

Conservative plate margin – in plate tectonics, a plate boundary where the relative movement of the two crustal plates is lateral, or past each other.

Conservation – the maintenance of a landscape (natural or man-made) in its current state.

Constructive plate margin – in plate tectonics, a plate boundary where the relative movement of the crustal plates is apart from each other allowing magma to rise from the mantle and solidify to construct new crust.

Constructive wave – a low height, low frequency wave where the net movement of material is up the beach as the swash is stronger than the backwash.

Consumer – two types:

• in human geography, a person buying a good or service.
• In physical geography, any organism that lives off the tissue of another organism.

Containerization – the development of standardized metal containers for cargo which can be transshipped between train, lorry and ship carriers. Revolutionized haulage by reducing transshipment times and replacing large numbers of labourers with crane technology.

Continent - one of the seven largest pieces of land on earth.

Continental climate – typical climates of interior areas well away from the influence of the sea. Tend to hot summers and cold winters with a large temperature range between the two. Low overall precipitation which tends to be at its highest in summer if convection allows.

Continental crust - is the layer of granitic, sedimentary, and metamorphic rocks which form the continents and the areas of shallow seabed close to their shores, known as continental shelves.

Continental drift – theory that the land mass of the earth was once held as a single continent which has since split into segments which have drifted apart and into the modern configuration of the continents. Proposed by Alfred Wegener in 1912, based on observed matches in the shape of continents, their geology and biological history, it was rejected as no satisfactory mechanism could be postulated. Has regained favour, though modified, in plate tectonic theory.

Continental plate – a segment of the earth’s crust made up of sial. Found mostly, but not exclusively, above sea-level.

Continental shelf – shallow sea floor fringing continents. That part of the continental plate that is currently flooded due to modern sea levels.

Continuous permafrost – within the Arctic Circle average temperatures rarely rise above zero. Water in the ground generally remains frozen apart from some superficial summer melting of perhaps the top few centimeters. The permafrost can be several hundred metres deep and is not broken.

Contour interval – the difference in elevation (height above sea-level) between adjacent contour lines.

Contour line – on topographical maps, the isolines connecting points of equal height above sea-level.

Contour ploughing - Ploughing so the furrows follow the contours of the slope i.e. they go horizontal across the slope not up and down the slope.

Contract farming – where large agribusinesses, usually food processing companies or supermarket chains, contract farmers to provide them with particular types of produce.

Conurbation – large, effectively continuous urban area produced as urban sprawl leads formerly separate settlements to coalesce.

Convection – transfer of heat in a gas or liquid by upward movement of the hotter, less dense portion. Found in atmospheric, oceanic and asthenospheric mediums.

Convection current – the circular movement of a liquid or gas undergoing convection in a limited space.

Convection plume – the upwelling part of a convection cycle in the mantle.

Convergent plate margin – see destructive plate margin.

Co-operative agriculture – smaller, individual farmers form a co-operative to reduce input costs through bulk buying and improve pricing through greater bargaining power.

Coral – a tiny animal (polyp) which exists in large colonies in warm, shallow, clear salt-water.

Coral reef – offshore accumulation of dead coral, usually with live coral on top.

Core – two main associations in geography:

• in physical geography, the central interior of the earth. Thought to be an inner core, mostly solid under extreme temperature and pressure, and an outer core, mostly liquid, both composed of iron and nickel.
• in human geography, an area that enjoys economic, social and political superiority in comparison to its surrounding area – the periphery or hinterland.

Core-periphery model – a model seeking to explain a spatial pattern of economic growth in which one centre or region in a country develops an economic advantage over the rest of the country. Several have been proposed.

Coriolis force – the effect of drag from the earth’s rotation on airflow.

Corrasion – see abrasion.

Correlation – the degree of association between two sets of data either positive – as one increases so does the other – or negative – as one increases the other decreases. Does NOT indicate causality.

Corrie – (also known as a cirque or cwm) a great bowl-shaped hollow at the head of a glacial valley. Accumulation of snow in a depression over many years forms a niche glacier which then erodes the corrie by plucking and abrasion in a rotational movement. Characterized by a steep back-wall and a rock lip at the lower, front end.

Corrie glacier – the glacier found in a corrie which has been responsible for its formation.

Corrosion – a generic term for chemical weathering.

Cottage industry – small-scale, home-based production.

Council housing – in the UK, housing funded by local government with help from central government. Started in 1919 to provide for low-paid workers and their families when forced to move due to slum clearance or when housing shortages forced prices out of reach. Housing remains in ownership of the local authority and tenants pay limited rent to it. Much of the better stock has now been transferred to private ownership.

Counterurbanisation – decentralisation of population from large urban areas to smaller ones or rural areas. Thought to be a result of both improved communication and connectivity as well as a reaction against the problems associated with large urban areas.

Crater – the depression found at the summit of a volcanic cone.

Craton – see shield area.

Creep – extremely slow downslope movement of soil. Caused by combination of factors which allow horizontal dislodging of particles which then subside under gravity. Factors include raindrop impact, soil expansion, vegetation stress and animal activity.

Cretaceous - in geologic time, a period lasting from 144m to 65m years ago.

Crevasse – a deep crack in the surface, usually in a glacier.

Cross-profile – cut away view through a feature from side to side.

Crust – solid, outer layer of the earth. Between 5 and 80km thick, it is made up of two types of material, continental or sial, and oceanic or sima which exist in large segments called plates.

Crustal plate – see crust.

Cuesta – where a more resistant strata of rock is left upstanding when less resistant strata on either side are degraded more rapidly. The dipping angle of the strata creates a steep scarp slope on one side (escarpment) and a more gentle dip slope on the other.

Cultivation – the preparation and use of land for crop growing.

Cumulative causation – the idea that one factor can trigger a sequence of events which reinforce and amplify the entire process concerned. Term coined by Myrdal to explain economic disparity between regions whereby an initial advantage in one then draws in resources to improve the position of the region at the expense of those surrounding. Also thought to work in reverse to explain economic decline.

Cuspate foreland – triangular beach form. Can be few hundred square metres to few hundred square kilometers.

Cusps – small hollows on beach fronts, a few metres across, which look like mini bays within the beach itself.

Cwm – see corrie

Cycle of poverty – the process which maintains conditions of chronic poverty in rural areas of ELDCs. A lack of money restricts, or more often precludes, investment in agricultural technology keeping yields low and thus little or no surplus for sale which maintains the lack of money.

Cyclomatic number – the number of circuits in a network.

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