ELSS Vocab List Flashcards
Ablation
The loss of ice and snow, especially from a glacier, through melting, evaporation and sublimation.
Acidification
Decreasing pH, e.g. of the oceans due to an increase in the uptake of CO2 from the atmosphere.
Active Layer
In areas of permafrost, the top layer of soil that thaws during the summer and freezes again during the autumn.
Adiabatic expansion
The expansion of a parcel of air due to decrease in pressure. Expansion causes cooling.
Albedo
The reflectivity of a surface: snow and ice have high albedos. Once ice forms on the earth the high albedo reflects solar radiation back into space, further reducing surface temperatures.
Aquifer
A water-bearing band of porous or permeable rock
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 synclinal structure.
Atmosphere
Thin envelope of gases (mainly nitrogen and oxygen) that surrounds the Earth
Biological pump
The ocean’s biologically driven sequestration of carbon from the atmosphere to deep sea water and sediment.
Biosphere
The space at the Earth’s surface and within the atmosphere occupied by living organisms.
Cap and trade
An internal scheme to control carbon emissions. A market-based solution to climate change where polluters either cut their emissions or incur extra costs by buying tradable carbon credits.
Carbonation
A process of chemical weathering where calcium carbonate rocks react with naturally acidic water to form calcium bicarbonate, a soluble product, which is removed by the water in solution.
Carbon Capture & 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 credits.
Carbon sink
A long-term store of carbon in ocean sediments, carbonate rocks etc.
Carbon source
Inputs of carbon to the atmosphere by respiration, combustion and decomposition.
Chelation
A type of chemical weathering caused by acids derived from rainwater and dead organic material.
Condensation
The phase change of water vapour (gas) to liquid (water).
Convection
The motion of a gas or liquid which when warmed rises until eventually it cools and sinks in a continuous circulation.
Decarbonation
The reduction or removal or carbon emissions from energy sources.
Decomposition
Process by which organic substances are broken down into simpler matter.
Desertification
The conversion of marginal land into desert brought about by naturally occurring periods of drought together with human mismanagement of the land.
Dew point
The critical temperature at which condensation occurs.
Discharge
The total volume of water flowing through a channel at any given point and is measured in cubic metres per second (cumecs).
Downwelling
The sinking of dense, salty (or cold) water in the oceans.
Dynamic equilibrium
A system displaying unrepeated average states through time.
Ecosystem
A group of organisms (plants, animals, bacteria) which interact with one another and the environment so that material is transferred between the living and non-living (air, soil, water) parts of the system.