Katabatic
A wind flowing down valley sides and floors, usually as air cools, condenses and sinks at night.
Keystone Species
One that has a sizeable and important impact on the integrity of the ecosystem as a whole.
Knoll
A small hill or mound of earth.
La Niña
The opposing phase to the El Niño Southern Oscillation, where 'normal' conditions are hyper exaggerated.
Lagoon
A calm, shallow body of water separated from a larger body of water by barrier islands or reefs or in the centre of an atoll.
Lahar
A mudflow caused by erupted materials such as ash, dust and lava from a volcanic eruption mixing with water.
Laminar Ice Flow
A type of flow in which the plains of glacial ice run in parallel and do not cross over one another.
Land Breeze
A breeze blowing towards the sea from the land, caused by land cooling more quickly than water.
Land Degradation
The slow loss of function from a terrestrial ecosystem due to negative outside influences.
Land Grab
The buying or leasing of large areas of land for commercial farming with little regard for the wellbeing of the people who previously used it to sustain their own livelihoods.
Land Hoarding
The act by which property developers buy up land but do not build on it immediately, instead waiting for the price of the land to rise and ensuring a higher profit upon sale.
Landfill
A location for the deposal or burial of waste material.
Landslide
The mass movement of rock and earth material at significant speed down a slope.
Lapse Rate
The rate at which air temperature falls with increasing altitude.
Latent Heat
The quantity of heat absorbed or released when a substance changes its physical state at a constant temperature.
Lateral Moraine
Parallel ridges of unconsolidated debris deposited along the sides of a glacier.
Latitude
An imaginary line running east to west around the Earth signifying how far north or south a place is from the Equator.
Latosol
Low fertility soils found under tropical rainforests with a relatively high content of iron, alumina and silica.
Lava
Hot molten or semi-fluid rock expelled by a volcano during an eruption and the resulting rock after its cooling and solidification.
Leaf Litter
The collection of plant matter such as leaves, twigs, branches and bark that collect on the ground as vegetation shed their material.
Least Developed Countries
Countries who sit amongst the twenty poorest in the world according to GDP per capita.
Lee Side
The side of a building or hill that faces away from the prevailing wind and is thus usually sheltered from it.
Levee
A naturally occurring or artificially constructed embankment which regulates water levels.
Life Expectancy
The average age at which an organism dies.
Limestone Pavement
A flat surface of exposed limestone formed by a glacier passing over horizontal beds of the rock.
Linear Settlement
A settlement that has historically spread out along a linear feature such as a river or a hill contour.
Liquefaction
When particles of soil become separated, usually as the result of an earthquake, and take on the properties of a liquid unable to support any weight.
Literacy Rate
The percentage of the population aged over fifteen years old who are deemed able to read and write.
Lithosphere
The solid outer layer of the Earth, made up of crust and solid mantle.
Little Ice Age
A period of cooling in Europe's medieval warm period where ice covered the surface of the continent.
Livestock
Animals that are bred and raised as part of an agricultural process to produce sellable goods.
Local Governance
Lower tier administration that works within a specific, localised region beneath the central (national) government.
Long Shore Drift
A coastal transportation process responsible for the movement of material in a zig-zag fashion along a beach.
Longitude
An imaginary line running north to south around the Earth signifying how far east or west a place is from the Greenwich Meridian.
Longline
Fishing Industrial fishing where nets are not used and instead fishermen favour a large number of rods and lines in order to catch fish.
Low Carbon Economy
A way of running a country that focuses on energy sources that emit low levels of green house gases.
Low Order Goods and Services
A good or service, usually inexpensive, that people buy on a regular (often daily) basis, such as bread, milk or newspapers.