Labour flexibility -how easy it is for a company to change the work that its staff does.
Labour mobility -two kinds:
Lag time - time that passes between the point when precipitation is at its highest over a particular drainage basin during a particular precipitation event, and the point when discharge in the river channel is at its highest in that drainage basin for that precipitation event.
Lahar - mudflow associated with volcanic activity. Surface water mixes with volcanic ash to produce the lahar.
Lake -a body of water on a continental mass. Usually refers to surface water stores which are still and composed of fresh water. However, can be used for saltwater bodies or underground stores if they are in cavities such as caverns.
Laminar flow -parallel flow of different portions of an overall flow.
Land breeze -a wind blowing from the land towards the sea. Often found at night under anticyclonic conditions when heat is lost rapidly from the land and the air above is cooled and increases in pressure. The relative warmth of air over the sea leads to rising air which draws wind from the land.
Landfill - a location for the disposal of human waste be it domestic, commercial or industrial. May be a brownfield site such as an old quarry which is filled in, or a purpose-built hole in the ground.
Land reform -imposed redistribution of land and/or changes in land ownership designed to increase agricultural productivity under the philosophy that owner-occupiers make more of an effort therefore as much agricultural land as possible should be owner-occupied.
LandSat -a remote-sensing satellite program run by NASA and the U.S. Geological Survey. The first satellite was launched in 1972 and lasted until 1978. In total, six LandSat vehicles have been put into orbit and two remain today (L5 and L7, L6 failed to launch).
Landscape - comprises the visible features of an area of land, including physical elements such as landforms, living elements of flora and fauna, abstract elements such as lighting and weather conditions, and human elements.
Landslide (also landslip) -a rapid downslope mass movement where water in the soil and rock has accumulated to sufficiently increase stress and lubricate bedding planes. The bedding planes will usually be (near) parallel to the angle of slope.
Land reclamation -the improving or recovering or even creation of land for human use. Marshy land may be drained; derelict land may be cleared; rock material may be dumped into shallow coastal waters to extend existing land out into the sea.
Land use - the dominant activity taking place on an area of land.
Lapse rates -the rates at which air temperature decreases with altitude. Three types:
Latent heat -release of heat during a change of state. Condensation of water releases latent heat to the atmosphere because it no longer needs the heat energy that was put in to change it from liquid to gas in the first place.
Latifundia -system of landholding found most commonly in Latin America. Land is held in ownership on a large, estate scale by a small elite class. The work is carried out by local people employed as farm labourers.
Latitude - the angular distance north or south of the equator on any meridian. Joining points of the same angle on all the meridians creates a line of latitude encircling the globe. Measured in degrees, minutes and seconds. Excellent explanation here: http://www.phy6.org/stargaze/Slatlong.htm
Leaching - the removal of minerals in solution from soils when water moves down through the soil and drains away.
Lee - sheltered side of a slope.
Leeward - the downwind area from a slope.
Leisure industry -the goods and services provided for consumption during leisure. Worldwide, the leisure industry has expanded rapidly since the 1970s as people have more time and more disposable income for leisure activities, as well as a tendency towards consumption rather than saving.
Lessivage - downward movement of clay particles through a soil in suspension as water passes through.
Levée -the naturally raised bank of a river. When flooding occurs, the water immediately begins to lose energy and deposits the larger load. With distance from the channel the deposited load is increasingly smaller. This leaves the banks higher than the rest of the floodplain. Deposition in the channel itself can then lead to the river being higher than the floodplain and the Levée may be artificially strengthened and/or heightened to protect from catastrophic collapse.
Life expectancy -average number of years that individuals are expected to live depending on where and when they are born and spend their lives. May be derived on national, regional or local scale.
Light industry -an industry in which the physical mass of raw materials used is relatively low. This can be misleading for an industry that uses large amounts of electricity drawn from a power grid rather than produced on-site as it removes the need for fuel to be delivered to the site. Generally however, light industries are low polluting and use fewer resources.
Limestone - a sedimentary rock formed from at least 80% calcium carbonate. This may have been deposited in the skeletal remains of marine creatures or from ooliths. E.g.s: chalk, carboniferous limestone, oolitic limestone.
Limestone pavement -a lagstone-pattern appearing on exposed, flat upper surfaces of a mass of limestone. Water runs along joints and cracks in the rock and rapidly enlarges them through carbonation. These cracks are called grikes. The blocks they leave defined are called clints.
Linkages - relationships between industries.
"the ability to identify, understand, interpret, create, communicate and compute, using printed and written materials associated with varying contexts. Literacy involves a continuum of learning to enable an individual to achieve his or her goals, to develop his or her knowledge and potential, and to participate fully in the wider society."
Lithification -the cementing of sediments to form rock.
Litter layer -dead organic matter lying on the surface and waiting for/in the process of decomposition.
Littoral - most properly the area at a coast between the highest and lowest tides. Generally used simply to refer to the shore.
Livestock - animals domesticated and kept by humans either for food or to do work.
Loam -a soil having roughly equal proportions of clay, sand and silt.
Location quotient -a statistical measure of concentration. The quotient indicates the geographical concentration of a particular activity in a particular region as a function of the expected concentration based on national average. The formula can be presented as:
LQ=%total workforce in region A working in industry X
%total national workforce working in industry X
so if an area has 15% of its workforce in agriculture when only 5% of the national workforce is employed in agriculture, the LQ=15/5=3.
LQ>1 indicates over-representation, or a concentration of that industry.
LQ=1 indicates expected concentration based on national average.
LQ<1 indicates under-representation, or a lack of that industry.
Loess -in glacial environments there is a large amount of small, fine-grained material found in the outwash plain. Strong winds often blow out from glacial areas as the cold surface cools the air above creating high pressure. These winds carry material away and deposit it elsewhere across wide areas to form loess deposits which are easily weathered into well-drained, fertile soils. Loess is not known to be forming at present and is associated with the Pleistocene.
Longevity - lit. long life. In geography, usually refers to humans living beyond 60 years of age.
Longitude -the angular distance east or west of the prime meridian on any meridian. Joining points of the same angle on all the meridians creates a line of longitude encircling the globe. Measured in degrees, minutes and seconds. Excellent explanation here: http://www.phy6.org/stargaze/Slatlong.htm
Longshore drift -the net movement of sediment along a coast. The direction of swash is usually not perpendicular to the coastline. Sediment is thus moved up a beach and across at the same time. As backwash occurs under gravity, its direction is more directly down to the sea (more perpendicular to the coastline), thus material it carries has a net sideways movement.
Lorenz curve -a line graph that portrays the (un)evenness of a geographical distribution. The vertical axis is cumulative percentage of the variable being examined. The horizontal axis is the rank order of the values. A perfectly even distribution will give a 45˚ line rising left to right. The more the line diverges from this, the more uneven, or more highly concentrated, the variable is.
Low tide - the lowest point to which the sea falls against the land in its daily vertical movement.
If you wait to do everything until you're sure it's right, you'll probably never do much of anything.