P Wave (Primary Wave)
A type of energy wave that is released during an earthquake and is the fastest to travel out from the focus.
Pacific Ring of Fire
A region around the edge of the Pacific Ocean where there are a high number of volcanoes and earthquakes due to it representing a series of plate boundaries.
Paddy Field
A field, usually found in Asia that can be flooded in order to allow for the growing of rice
Pandemic
A disease that is prevalent over a whole country or the world.
Pangea
The large landmass, or supercontinent that existed on Earth approximately 200 millions years ago.
Paradigm
A distinctive set of thought patterns or ways of doing things.
Participatory Decision Making
A process by which the general public express their own opinions about a potential change and influence more central actors in the process.
Pastoral Farming
Farming that produces livestock for meat, milk, wool, hide and other animal products.
Patriarchal System
A social viewpoint in which the lives of men are placed above that of women.
Peak Discharge
The maximum volume of water passing a certain point per unit of time in a river system.
Peak Land Value Intersection (PLVI)
The region within a settlement that holds the greatest land value.
Peak Oil (Production)
The point at which the maximum rate of oil extraction and production is reached.
Percolation
The movement of water downward and radially through the subsurface soil layers, usually continuing downward to the groundwater.
Perennial Crop
A food plant that lives for more than one year, and thus reduces the amount of inputs needed to keep production sustainable.
Periphery Region
An area with low levels of productivity, innovation and employment.
Periurban
An area that is directly next to an urban area.
Peters Projection
A cylindrical map projection which tries to show the position of the continents relative to the poles but in doing so distorts their shape.
Photovoltaic Cells (PV Cells)
An electronic device installed on the outside of a building or on a solar farm that converts the Sun's light into electricity.
Physical Water Scarcity
A state whereby a country's economic ability to gain water is unhampered but where there is a limited supply physically for demand to be met.
Physical Weathering
The break up of rock material in situ without a change in its chemical composition.
Piracy
An act of criminal violence at sea that can typically include kidnapping and holding up a ship for its cargo.
Plagioclimax
A state when human activity has restricted the ecosystem from progressing any further.
Plantation
A large farm concentrating on producing a single cash crop, usually for export.
Plate Tectonics
The theory that states that the Earth's crust is split into a number of plates that slowly move around, causing earthquakes and volcanoes.
Plateau
A large flat area of land that is raised above the land surrounding it.
Player
Someone who has a role to play in the decision making process surrounding an issue.
Plinian Eruption
A highly explosive volcanic eruption with dense clouds of gas and tephra being propelled upwards for many kilometres.
Plucking
The erosional process resulting in the direct removal of loose bedrock by the impact of water or by incorporation into glacier ice.
Plume
An upwelling of molten rock through the asthenosphere to the lower lithosphere, forming a hot spot which causes volcanic activity at the surface.
Plunge Pool
A pool at the base of a waterfall, often undercutting the sheer rock face, formed as a result of hydraulic action, eddying, cavitation or pothole erosion.
Pluvial
Connected to or relating to rainfall.
Pollution
A substance, often alien to the host environment which causes an undesirable change in the physical, chemical or biological characteristics of the natural environment.
Pollution Dome
A mass of polluted air in and above an industrial complex of city which is prevented from rising by the presence of an inversion above it.
Population Density
The number of people in a given unit of area.
Population Distribution
The spread of people across a specific region or country, usually measured in people per square kilometre.
Population Policy
A government initiative that aims to control the number of people in the population of a country or region.
Population Pyramid
A graphical method of representing the number of people of each sex and in different age categories.
Population Structure
The variety of ways in which one might characterise a population, such as by age, sex, ethnicity or socio-economic background.
Portable Water
Water that is clean enough for drinking and for use in cooking.
Positive Feedback
Any output that when viewed as an input for the same system allows the system to regenerate and continue to run.
Post colonialism
The processes and cultures left by the legacy of the European colonial era in the countries they took over.
Potable Water
Water that is safe to drink.
Pothole
A roughly circular hole in the bedrock of a river, often enlarged by pebbles inside it colliding with the bedrock as the water swirls.
Poverty Cycle
A model to show how once the factors for poverty are in place it can be difficult to move out of that sphere due to their interconnectedness.
Poverty Line
The estimated minimum level of income needed to secure the necessities of life.
Powder Snow
Snow that has newly fallen and not been compacted by humans or the weight of more snow on top of it.
Power Station
An industrial facility where electrical power is generated for distribution.
Precipitation
Moisture that falls from the sky, usually in the form of rain or snow.
Pre-Shock (Foreshock)
A small earthquake that happens just before a larger one.
Primary Effects
The direct impacts of a hazardous event that usually happen in the short term.
Primary Industry
The section of industry concerned with the harvesting of raw materials and food stuffs.
Primary Product Dependency
A situation where a country over-relies on the productivity of farming, mining and forestry industries.
Primate City
The primate city is the largest most dominant city in a region.
Privatisation
The removal of state ownership or control of a property or business which then passes to the private sector.
Product Stewardship
The idea that everyone involved in the production and marketing of a particular product has a responsibility to see that it is made in the most environmentally friendly way.
Progressive Taxation
A system of taxation where those who earn and own the most wealth pay the most in tax.
Pro-Natalist Policy
A birth control policy that seeks to increase the number of babies born in a particular country.
Proven Oil Reserves
The amount of oil that is extractable through economic and technical means.
Pull Factors
The reasons why a person decides to immigrate into a country or region.
Purchasing Power Parity
The power one’s money has to buy everyday items in comparison with the power it has in other countries or regions.
Push Factors
The reasons why a person decides to emigrate from a country or region.
Pyramidal Peak (Horn or Aiguille)
A post-glacial feature which was formed by the carving of glaciers on four sides of the same peak and creating four corries back to back.
Pyroclastic Flow
A dense, destructive mass of gas, ash, dust and rocks explosively ejected from a volcano during a highly explosive eruption.
Quality of Life
The general wellbeing of individuals and societies, indicated by measures such as health, education level and disposable income.
Quarry
An excavation from which materials such as rocks, sand and minerals are extracted for building.
Quaternary Industry
The section of industry concerned with research and development as well as technological advancement.
Quota
A set numerical limit for the amount of goods that can be produced or taken, for example, fish.
Racism
Discrimination and prejudice based on someone’s race.
Radiation
Energy travelling in the form of electromagnetic waves, including visible and UV waves such as those released by the Sun.
Radioactivity
The emission of ionising radiation or particles caused by the natural disintegration of atomic nuclei.
Rain Gauge
An instrument, often sunk into the ground, used for measuring precipitation.
Rain Shadow
The dry area on the lee side of a mountain which receives little rainfall as a result of the mountains blocking the preceding wet weather systems.
Rapids
Areas of greatly disturbed water across a river caused by a continuous and relatively gentle slope.
Rationalisation
The movement from a society based on traditions and emotional responses to one based on more scientific and economic principles.
Raw Material
A substance in its natural form which it used to manufacture something else.
Rebranding
The process by which the physical appearance and / or cultural identity of a place is changed to make it more attractive.
Recession
A temporary decline in the economy shown by a fall in gross domestic product for at least six consecutive months.
Recolonisation
The re-establishment of a species in a habitat where it was formerly found.
Recycling
A process by which used goods and materials can be remade into new ones.
Reforestation
Replanting of trees and plants in an area that had previously been cleared of vegetation.
Refugee
A migrant who has moved in order to escape real or feared persecution based on their race, religion, nationality or political opinion, or to flee war or the effects of a natural hazard.
Regeneration
A process of land redevelopment, normally in an urban area, in order to modernise it, often following a change in the local economy.
Regressive Population Pyramid
A population pyramid which shows a country has a declining birth rate and a low death rate.
Rejuvenation
The process of restoring something to how it may have looked as new, often by simple cosmetic touches.
Relative Poverty
A state of living in poverty compared others within a community, region or country.
Relief
The shape of the land.
Relief Rainfall (Orographic Rainfall)
Precipitation that falls as a result of air being forced to rise as it ascends to go over a mountain or hillside.
Remittances
Money paid by migrants to their families and friends who remain in their home country.
Renewable Energy
The power made from energy resources that will not run out within one's lifetime.
Replacement Level
The number of babies needed to be born to each woman in a population to replace the number of people who are dying.
Reserves to Production Ratio
The amount of a non-renewable resource left expressed in a numerical time value for the amount of use left.
Reservoir
A body of water that pools as a result of the placement of a dam.
Re-shoring
The process of businesses re-locating production to the UK.
Resilience
The ability to reduce the loss experienced from a natural hazard or natural phenomena, or to return to an original state more quickly by having specific measures in place.
Resource Depletion
The process by which a resource is used up fasting than it can be replenished.
Resource Nationalisation
The process by which a national resource is owned by the state rather than by a private industry.
Resource Substitution
A process whereby a different resource is used in order to meet demand when another resource is either exhausted or temporarily too expensive to use.
Return Period
The length of time between events - including droughts, floods and earthquakes - of a given magnitude, calculated using continuous records kept over a number of years.
Reurbanisation
The repopulation of urban areas by people who have since moved to rural spaces.
Revetment
A (usually) wooden structure that sits in the centre of the beach, parallel to the coastline in order to protect the upper beach and any cliffs from wave erosion.
Ria
The seaward end of a river valley which has been flooded as a result of a rise in sea level or a fall in land level.
Richter Scale
A scale, related to the amplitude of the ground wave and its duration - of the magnitude of earthquakes, ranging from 1 to 10.
Ridge
A glacial features formed by the movement of two glaciers eroding against either side of a hill or mountain.
Rip-Rap
A barrier used to defend river banks or a coastline from water erosion where stones and rocks are piled up to increase friction and slow the power of the water.
Risk
The likelihood of suffering adverse effects from a hazard.
River Cliff
A steep, concave curve created on the outside of a meander bend by the erosive effect of fast flowing water.
River Discharge
The volume of water flowing through a given point in a river in a given time.
River Profile
A graphical representation of a river, and how it changes, from source to mouth.
Rodgers Model
A theory that highlights the idea that despite equal inputs, a city that is able to build in sustainable processes in its core will have reduced waste and outputs.
Rotational Slip
A mass movement whereby a rock moves either side of a fault plane in a curved path.
Rural Idyll
A picturesque and romantic, though often in reality flawed, perception of the countryside and rural life.
Rural-Urban Fringe
An intermediate transition zone around a town or city where urban functions and activities impinge on those that are agricultural and rural.