Geography Overview

Ablation

The loss of ice and snow especially from a glacier through melting evapouration and sublimation

Absolute humidity

The mass of water vapour in a given volume of air

Abstraction

The extraction of water from rivers and boreholes for public water supply

Abyssal plain

The deepest part of the ocean covering vast areas of ocean floor submarine mountain chains and trenches interrupt the relatively flat plain

Accumulation

The addition or gain of snow and ice to a glacier overtime

Acidification

Decreasing pH e.g. Of the oceans due to an increase in the uptake of CO2 from the atmosphere

Active layer

The near surface layer in a periglacial environment which seasonally freezes and thaws

Adiabatic expansion

The expansion of a parcel of air due to a decrease in pressure. Expansion causes cooling

Advanced countries (ACs)

Countries that share a number of important economic characteristics including well-developed financial markets high degrees of financial intermediation and diversified economic structures with rapidly growing service sectors

Advection

The horizontal movement of an air mass which often results in either heating or cooling

Aeolian

Erosion also transportations and depositional processes by the wind

Aggradation

The deposition of sediment in a river channel which results in a rise in the bed elevation

Agribusiness

A large scale farming practice e run on business lines

Afro-ecosystems

An ecosystem that is managed to produce food

Alases

Flat-floored steep side steep-side depressions in periglacial environments

Albedo

Proportion of sunlight reflected from a surface

Algal bloom

A rapid increase in algae in a water system

Alkaloid

A naturally occurring chemical compound the active ingredient in many medical drugs e.g. morphine

Alluvial fan

A cone of sediment deposited by the river where it leaves a steep upland course and enters a lowland area

Abthropocene

The current geological period where humankind is the main driver of environmental change

Appropriate technology

Technology which is appropriate in its context of use it is small scale can be managed and often uses skills available in the local community

Aquifer

A water-bearing band of porous or permeable rock

Archipelago

A closely grouped cluster of islands

Arête

A narrow knife edged ridge between two corries

Artesian aquifer

A confined aquifer containing groundwater that when tapped will rise to the surface under its own pressure

Artesian pressure

The hydrostatic pressure exerted on groundwater in a confined aquifer occupying a synclical structure

Aspect

The direction a slope faces

Asthenosphere

The layer in the earths mantle below the lithosphere the high temperatures cause the rocks to soften and become viscous meaning the can easily deform

Asylum seeker

A person who seeks entry to another country by claiming to be a refugee

Atmosphere

The thin envelope of gases (mainly nitrogen and oxygen) that surrounds the earth

Attrition

The erosion of sediment transported by rivers glaciers waves and wind

Backwash

Flow of water down a beach after a wave has broken

Bajada

A series of alluvial fans that merge to form a continuous apron of sediment along a mountain front in dry land regions

Balance of payments

Difference between a country's inflows and outflows of money, including all transactions with the rest of the world for goods and services flows of FDI and migrant remittances over a period of time

Barchan

A discrete crescent shaped sand dune with horns pointing downwind

Barrage

A dam built across an estuary or bay so that the rise and or fall in the tides can be used to generate energy by the turning of turbines

Base flow

Water input to streams and rivers from natural reservoirs such as aquifers, pear bogs, soils etc.

Beach recharge

The addition of sediment to a beach by humans to increase its size and volume

Benioff zone

Boundary between a subduction ocean plate and the over-riding continental plate at a destructive boundary

Bio-prospecting

The discovery and commercial exploitation of biological resources e.g. Genetic material in organisms

Biodegrade

The breakdown of a substance through biochemical reactions or the actions of organisms such as bacteria into different compounds

Biodiversity

The number of different plant, animal, fungi etc. Species in a given area

Biodiversity hotspot

A region that is rich in biodiversity and where species and habitats are threatened with destruction

Biological weathering

The breakdown of rocks through the chemical and physical action of living organisms

Bioluminescence

The ability of some organisms to generate light from their bodies

Biopiracy

The exploitation of medicinal drugs from wild environments by pharmaceutical companies with little or no benefit to indigenous people

Biosphere

The space at the earths surface and within the atmosphere occupied by living organisms

Black smoker

Hydrothermal vent on the ocean floor at constructive or destructive plate boundaries. The water carries a high amounts of metal sulphides

Block disintegration

Physical weathering of massive jointed rocks which result in boulder-sized rock debris

Blockfield

A large expanse of boulders strewn across a level surface, often in mountain environments

Blue water navy

A navy capable of operating away from its home bases and across the deep oceans

Butte

An isolated steep sided flat topped rock outcrop

Caldera

Large- scale volcanic crater formed as a result of an explosive eruption which emptied the magma chamber causing the volcano sides to subside

Canopy

The uppermost layer of treetops and branches in a forest or woodland ecosystem

Cal and trade

An internal scheme to control carbon emissions. A market-based solution to climate change where pollutants either cut their emissions or incur extra costs by buying tradable carbon credits

Capital intensive

High levels of investment in manufacturing in plant and machinery per employee

Capital

Accumulated wealth of any kind used in producing more wealth; this may include tangibles such as machinery, buildings, land, and intangibles such as money, investment finance, company stocks

Capitalist

The Socio-economic system in which production of goods and services takes place to generate profit. A key driving force in the system is people's desire for gain and self-interest.

Caprock

A resident layer of rock often in a plateau-like surface, which protects older weaker rocks from denudation

Carbon capture and storage

The removal of CO2 from emissions by thermal power stations and its storage in disused oil and gas wells underground

Carbon credits

Allowances that permit given levels of CO2 emissions by businesses. Excess emissions must be covered by trading carbon credits

Carbon fertilisation

Rising CO2 levels in the atmosphere which increase photosynthesis and stimulate plant growth

Carbon offset

Market-based approach to limiting carbon emissions. Businesses receive annual carbon quotas (credits). These can be sold/bought on international carbon markets.

Carbon sink

A long term store of carbon in ocean sediments, carbonate rocks, forests etc.

Carbon source

Inputs of carbon to the atmosphere by respiration, combustion and decomposition

Carbonaceous rock

Rocks mainly comprising the fossilised remains of plants e.g. Coal and lignite

Carbonate rock

Rocks compromising carbonate minerals e.g. CaOC3 such as limestone and chaulk

Carrying capacity

The maximum number of a species that can be supported in a given area in a sustainable way.

Catchment

The area drained by a river and its tributaries I.e. Drainage basin

Central tendency

The middle value in a data set e.g. Median

Chelation

A type of chemical weathering caused by acids derived from rainwater and dead organic material

Chemical weathering

The in situ brake down of rocks by chemical processes such as oxidation, solution and hydrolysis

Choropleth map

A numerical map with areas shaded in proportion to the values they represent

Cirrus cloud

A high altitude, feather-like cloud made of ice crystals.

civil society

NGOs and other organisations that are independent of governments, working voluntarily, either individually or collectively, in support of citizens and communities throughout the world.

closed system

A system with inputs and outputs of energy, but without any movement of material across system boundaries.

Coastal squeeze

the erosion of mudflats, sand flats and beaches, trapped between rising seal level and hard coastal defence structures (e.g sea walls)

Coefficient of determination

The square of the correlation coefficient showing the % of change in u explained by x

Cold seeps

Low temperature mineral-rich springs flowing from the ocean floor

Commodity

A good material (not a service) interchangeable through trade or commerce such as a raw material

Communicable disease

An infectious disease that spreads from host to host

Comparative advantage

The principle that countries or regions benefit from specialising in an economic activity in which they are relatively more efficient or skilled

composite cone volcano

A strato-volcano

Comprehensive redevelopment

The planning and rebuilding of a substantial part of an urban area involving the demolition of nearly all of the previous buildings and infrastructure

Compressing flow

The movement of glacial ice down a gentle gradient, during which it thickens

Concordant

A coastline with bands of different geologies lying parallel to the shore

Condensation

The phase change of water vapour (gas) to water (liquid)

Contagious diffusion

The process by which a disease spreads through direct contact with a carrier

Contagious disease

A disease spread by contact or indirect contact between people, e.g. Ebola

Containerisation

The shipping of goods (by road, rail and sea) in standard-sized metal boxes. It allows efficient, merchandised handling of large volumes of goods and lowers transport costs

Continental drift

The theory that the continent are mobile and have moved across the Earth's surface through geological time

Continental rise

Gently sloping ocean floor between the continental slope and the abyssal plain

Continental shelf

The gently sloping offshore extension of a container extending into the ocean as far as the continental slope

Continental slope

Where the continental shelf becomes steeper as it descends to the deep ocean

Conurbation

Large urban area in population and areal terms, made up of the merging together of previously separate towns and cities

Convection

The motion of gas or liquid which when warmed rises until it eventually cools and sinks in a continuous circulation

Coral bleaching

The loss of algae (which give coral its colours) from coral due to an increase in water temperature

Core region

An area where economic activity is concentrated and living standards at relatively high

Corporate social responsibility

Commitment and initiative of a corporation to assess and take responsibility for its social and environmental impact. This includes its ethical behaviour towards the quality of life of its work force, their families and local communities, and its contribution to economic development and the natural environment

Corrasion

The scouring and erosion of rock surfaces by sediments transported by rivers, glaciers, waves and wind (also known as abrasion)