geography-key terms

Hotspot volcanoes

These are found in the middle of tectonic plates and are thought to be fed from the underlying mantle (a thick layer of high-density rocks lying between the Earth's crust and its molten core). These volcanoes occur where the mantle is unusually thin and hot. The summits of the Hawaiian islands are classic examples.

Subduction zones

Broad areas where two plates are moving together, often with the thinner, more dense oceanic plate descending beneath a continental plate. Fold mountains form at the edge of the overriding plate, with associated volcanic activity. Stress between the two plates also triggers earthquakes.

Paleomagnetism

Results from magma locking in the Earth's magnetic polarity when it cools. Scientists can use this to reconstruct past plate movements.

Hazards

These are natural events that threaten or actually cause injury and death, as well as damage and destruction to property.

Disasters

These occur when hazards have a significant impact on vulnerable populations. Officially, a hazard becomes a disaster when 100 or more people are killed and/or 100 or more people are affected.

Tectonic hazard profile

A technique used to try to understand the physical characteristics of different types of hazard, such as earthquakes, volcanic eruptions and tsunamis.

Stakeholders

Individuals, communities, organisations, businesses and governments with a specific interest in a situation - in this instance, in hazard risk and hazard mitigation.

Mega-disasters

These result from tectonic hazards and show several diagnostic features: ● They are large-scale in terms of the area involved and their economic and human impacts. ● They pose huge challenges, particularly at the emergency stage. ● They usually require substantial amounts of international disaster aid.

Mitigation

Any action taken to reduce or eliminate the long-term risk to human life and property from natural hazards. Those actions are largely the outcome of stage 5 in the hazard management cycle (Figure 1.8). However, they are also likely to be taken during stage 3, sometimes referred to as adjustment or adaptation.

Preparedness

Educating people about what they should do in an emergency (where to seek shelter, how to assist others) as well as improving warning systems and training, and equipping rescue teams. It is focused on the emergency stage immediately following a hazard.

Glaciation

The modification of landscapes while covered by ice sheets or glaciers.

Periglaciation

The modification of landscapes located adjacent to the margins of glaciers and ice sheets.

Stadials and interstadials

Short-term fluctuations within glacial periods. Stadials are colder phases that lead to ice advances, while interstadials are slightly warmer phases during which ice sheets and glaciers retreat.

Basal sliding

Occurs where ice temperatures are at or close to 0°C and a layer of basal meltwater forms between the ice and the bedrock.

Regelation

Occurs where basal ice is forced against a rock obstacle; it melts and then refreezes on the down-glacier side. The temporary meltwater acts as a lubricant.

Internal deformation

A plastic-like quality caused when, under pressure, ice crystals move slightly relative to each other.

Subglacial

locations lying beneath the base of a glacier or ice sheet.

Proglacial

locations lying close to the ice front of a glacier or ice sheet.

Periglacial

locations where frost action and permafrost processes dominate.

Paraglacial

locations recovering from the disturbance of glaciation.

Abrasion

The process by which solid rock is eroded by rock fragments being transported by glaciers.

Plucking

The detachment of joint-bounded blocks by glaciers. It was thought that the ice froze onto the rock and wrenched blocks of it away. However, it is now believed that the breaking away of blocks is due to the movement of the glacier.

Littoral zone

The wider coastal zone, which includes adjacent land areas, the shore and the shallow part of the sea just offshore. It comprises four sub-zones: coast, backshore, foreshore and nearshore

Dynamic equilibrium

The balanced state of a system when inputs and outputs balance over time. If one of the inputs changes, then the internal equilibrium of the system is upset. By a process of feedback, the system adjusts to the change and the equilibrium is regained.

Halophytes

Plants that can tolerate salt water, be it around their roots, being submerged at high tide or being sprayed by the sea.

Xerophytes

Plants that can tolerate very dry conditions, such as those found in coastal sand dunes.

Plant succession

The sequential development of vegetation from its initial establishment on bare ground through to the ultimate vegetation cover or climax plant community.

Fetch

The uninterrupted distance across water over which the wind blows. It is the distance over which waves are able to grow in size.

Swash

The flow of seawater up a beach as a wave breaks.

Backwash

The return flow of seawater back down the beach to meet the next incoming wave.

Beach morphologyy

The shape of a beach, including its width and slope (the beach profile) and features such as berms, ridges and runnels. It also includes the type of sediment (shingle, sand, mud) forming the beach.

Currents

Flows of seawater in a particular direction driven by wind, tides and differences in density, salinity and temperature.

Sediment cells

Long stretches of coastline that operate as almost selfcontained physical systems. In each sediment cell there are sources (inputs), where sediment is generated (e.g. eroding cliffs and beaches), transfer zones (flows), which are stretches where sediment is moving along the coast by longshore drift and currents, and sinks (outputs), locations where the dominant process is deposition (e.g. spits and offshore bars).

Weathering

The disintegration and decomposition of rocks in situ by the combined actions of the weather, plants and animals.

Mass movement

A collective term for the processes responsible for the downslope movement of weathered material under the influence of gravity.

Environmental refugees

People and communities forced to abandon their homes due to natural processes. These processes may be sudden, as with landslides or volcanic eruptions, or gradual, such as coastal erosion and rising sea levels.

Transnational corporations (TNCs)

Businesses whose operations are spread across the world, operating in many nations as both makers and sellers of goods and services.

Glocalisation

The changing of the design of products to meet local tastes or laws.

Trade blocs

Voluntary international agreements that encourage the free flow of goods and capital between member countries.

Special economic zone (SEZ)

An industrial area, often near a coastline, where favourable conditions are created to attract foreign TNCs.

Foreign direct investment (FDI)

A financial injection made by a business into another country's economy, either to build new facilities (factories or shops) or to acquire, or merge with, a firm already based there.

Global shift

The international relocation of different types of industrial activity, especially manufacturing industries.

Deindustrialization

The decline of regionally important manufacturing industries in terms of either workforce numbers or output and production measures.

Cultural diffusion

The gradual spread of culture from an influential civilisation.

Cultural imperialism

The practice of promoting the culture/language of one nation in another. It is usually the case that the former is a large, economically or militarily powerful nation and the latter is a smaller, less affluent one.

Diaspora

The dispersion or spread of a group of people from their original homeland.

Economic migrant

A person who moves from one country to another in order to find work and improve their standard of living and quality of life.

Resource nationalism

A growing tendency for state governments to take measures ensuring that domestic industries and consumers have priority access to the national resources found within their borders.

Ethical consumption

This occurs when the consumer takes into account the costs (economic, social and environmental) of producing food and goods, and of providing services.

Connection

Any type of physical, social or online linkage between places. Places may keep some of their characteristics or change them as a result.

Deindustrialization

The process of economic and social change due to a reduction in the industrial capacity or activity of a country, region or city. A process widely experienced in the developed world with the global shift of manufacturing to emerging economies.

Quality of life

The level of social and economic well-being experienced by individuals and communities, measured by various indicators such as health, longevity, happiness and educational achievement.

Gentrification

The movement of middle-class people back into rundown inner-urban areas, resulting in an improvement of the housing stock and image.

Deprivation

A condition when a person's well-being falls below a level generally regarded as a reasonable minimum. Measuring deprivation usually relies on indicators relating to employment, housing, health and education.

Studentification

Social, economic and environmental change brought about by the concentration of students in particular areas and cities, usually located close to universities.

Perception

The 'picture' or 'image' of reality held by a person or group of people resulting from their assessment of received information.

Sink estates

Housing estates characterised by high levels of poverty, deprivation and crime, such as domestic violence, drugs and gang warfare.

Marginalisation

The social process of being made to feel apart or excluded from the rest of society. This leads to feelings of belonging to an underclass that is discriminated against.

Infrastructure

The basic physical systems of a place. Economic infrastructure includes highways, energy distribution, water and sewerage facilities and telecommunication networks. Social infrastructure includes public housing, hospitals, schools and universities.

Stakeholder

An individual, group or organisation with a particular interest in the actions and outcomes of a project or issue-solving exercise.

Population density

The number of people per unit area (usually per sq km), i.e. the total population of a given area (a country, region, city or place) divided by its area.

Natural change

The outcome of the balance between births and deaths in a population during a given period. Natural increase occurs when births exceed deaths; natural decrease occurs when deaths exceed births.

Net migration

The balance at a national level between international arrivals (immigrants) and international departures (emigrants) during a given period. However, with areas within a country, the term takes into account both international and internal. The balances can be either positive or negative.

Population pyramid

This is, in effect, a histogram, constructed in one-, five- or ten-year age groups, with males on one side and females on the other. The base of the pyramid represents the youngest age group and the apex the oldest.

Rural idyll

A 'chocolate box' image of quaint villages set in beautiful countryside. A place thought to be free of most of the negatives associated with urban living.

Enclave

A group of people surrounded by a group or groups of entirely different people in terms of ethnicity, culture or wealth.

Assimilation

The process by which different groups within a community intermingle and become more alike. The process particularly applies to the integration of immigrant ethnic groups.

Gentrification

The movement of middle-class people into rundown, inner-urban areas and the associated improvement of the housing stock and area image.

Management

A set of actions that facilitates the transition from one situation to another. More specifically, those actions might be aimed at solving or ameliorating a particular problem or issue.

Stakeholder

An individual, group or organisation with a particular interest in the actions and outcomes of a project or issue-solving exercise.

Blue water

Freshwater stored in rivers, streams and lakes - the visible part of the hydrological cycle.

Green water

Freshwater stored in the soil and vegetation - the invisible part of the hydrological cycle.

Residence time

The average time a water molecule will spend in a store or reservoir.

Fossil water

Ancient, deep groundwater from former pluvial (wetter) climatic periods.

Cryoshpere

Water frozen into ice and snow.

Desertification

The degradation of land in arid and semi-arid areas resulting from various factors, including climatic variations and human activities.

Ecosystem stress

Refers to constraints on the development or survival of ecosystems. The constraints can be physical (drought), chemical (pollution) and biological (diseases).

Ecosystem resilience

The capacity of an ecosystem to recover from disturbance or to withstand an ongoing pressure, such as drought.

Water insecurity

This exists when a population no longer has sustainable access to adequate quantities of water of acceptable quality. Adequate, that is, in sustaining human wellbeing and socio-economic development and for ensuring protection against waterborne pollution and disease.

Safe water

Water that is sufficiently clean to be fit for human consumption and use.

Desalinisation

The conversion of salt water into freshwater through the partial or complete extraction of dissolved solids.

Sequestering

The long-term storage of carbon dioxide and other forms of carbon.

Photosynthesis

The process by which plants capture carbon dioxide from the atmosphere and then store (sequester) it as carbon in their stems and roots. Some will also be stored in the soil.

Carbon cycle pumps

The processes operating in oceans that circulate and store carbon.

Thermohaline circulation

The global system of surface and deep-water currents within the oceans driven by differences in temperature and salinity.

Carbon pathways

The routes taken by flows of carbon between stores.

Energy mix

The combination of different available energy sources used to meet a country's total energy demand.

Primary energy

The forms of energy found in nature that have not been subjected to any conversion or transformation process, for example water (watermills) and wind power (windmills) or the burning of gas in heating the home and by motor vehicles.

Secondary energy

Derived from the conversion of primary energy. The most important secondary energy is electricity, which is derived from many primary sources.

Land conversion

Clearing a natural ecosystem and using the space it occupied for a different purpose.

Ocean acidification

The decrease in the pH of the oceans caused by the uptake of carbon dioxide from the atmosphere.

Ecosystem resilience

The level and speed of disturbance that ecosystems can cope with while still maintaining their original status.

Adaptation

In the present context, any action that reacts and adjusts to changing climate conditions.

Mitigation

In the present context, any actions that either reduce or eliminate the long-term risk and hazards of climate change.

Hyperpower

An unchallenged superpower that is dominant in all aspects of power (political, economic, cultural, military) - for example, the USA from 1990 to 2010. Is there a hyperpower today?

Geo-strategic location

A location that commands access to and control over a large territory and its resources.

Neo-colonialism

Refers to an indirect form of control which means that newly independent countries are not masters of their own destinies.

Free trade

The exchange of goods and services free of import/export taxes and tariffs or quotas on trade volume.

Inter-governmental organisations (IGOs)

Mainly global organisations whose members are nation states that uphold treaties and international law.

Sanctions

The aim is to force or persuade a country back to the negotiating table without using military force. Sanctions can be diplomatic, economic, military or even sporting.