Talus -the accumulation of weathered material on a slope.
Tectonic- The geological processes by which rocks are deformed and that produces features of the earth's crust.
Temperate -moderate or mild conditions as found between 23.5˚ and 66.5˚ of latitude.
Temperate deciduous forest -forest that dominates in temperate areas. Trees are deciduous i.e. they shed all their leaves during the winter season (or during drier periods).
Temperate grasslands -extensive natural grasslands in the continental interiors of temperate regions.
Temperature inversion -a situation where temperature of air in the lower troposphere increases with height.
Temperature range -the difference between maximum and minimum temperature. Can be measured over different timescales, and for absolute readings or averages.
Tenure -the conditions of occupancy of a piece of land.
Terminal moraine - are ridges of unconsolidated debris deposited at the snout or end of the glacier.
Terrace -an area of flat ground set into or onto a steep slope.
Tertiary sector -those industries providing services, both private and public.
Thalweg - the deepest part of the river channel.
Thermosphere -the upper layer of the atmosphere above 80km from the earth surface. Extremely hot (up to 1200˚C) due to absorption of radiation by gases.
Throughflow -the movement of water through a soil to a river channel.
Tidal energy -the energy involved in tidal movements of water which is available to be harnessed if those movements can be used to turn turbines.
Tidal flat -the surface exposed only at low tide.
Tidal range -the difference in height between low tide and high tide.
Tidal zone -the area between the low water mark and the high water mark.
Tide -the periodic rise and fall of sea level due to the gravitational pull of the sun and moon. The tidal range will be determined by the relative positions of these two bodies which can work with or against each other.
Till -glacial deposits.
Tombolo -a sand deposit which joins an island with a nearby land mass.
Topographical map -a map of surface feature, natural and human, drawn to scale.
Topological map -a map which uses points and straight lines to show relative positions and linkages e.g. one showing a rail network.
Tor -blocks of granite which appear balanced on one another.
Tornado -a localized, anti-clockwise spiral of wind with extremely violent wind speed and uplift.
Toxic waste -poisonous by-products of industrial processes which use metals. May be solid, liquid or gaseous.
Trade bloc -a collection of countries who agree to make trade between themselves easier and to maintain barriers to trade with countries outside of the bloc.
Trade winds -easterly winds which blow from the tropics towards the equator. So named as they were first identified by sailors who used them to cross the Atlantic.
Transect -a line drawn between points and then used to investigate changes in surface features along that line.
Transhipment -the transfer of cargo between ships or between two different modes of transport.
Translocation -the movement of soil components within the soil.
Transmigration -the mass resettlement of people within a country to alleviate overcrowding or localized overpopulation.
Transpiration -the loss of water from plants through the stomata in the leaves.
Transnational corporation -one which operates in more than one country. Traditionally, high value operations such as headquarters, research and marketing located in EMDCs while manufacturing took place in ELDCs.
Trellised drainage pattern -where the pattern of streams is such that the tributaries (or subsequent streams) to the main (or consequent stream) join at right-angles to it. The pattern may become more complex with the addition of obsequent streams. The pattern develops on areas of alternate bands of resistant and less resistant rock.
Tributary -one river joining another. Usually the smaller of the two is labelled the tributary, and the larger is the main channel.
Tricellular model -the basis of the modern understanding of the general circulation of the atmosphere as it relates to the troposphere. Air rises at the equator due to convection and is forced to move to higher latitudes when it reaches the tropopause. Having cooled it sinks over the tropics and drags down air adjacent to it. On reaching the surface, the air is again forced to split; some returning to the equator and some moving to the mid-latitudes. This warmed air meets cold polar air at about 60-of latitude and is forced to rise, again splitting at the tropopause; some returning to the tropics and some moving over the poles. This circulation forms three cells known as the Hadley, Ferrel and Polar respectively.
Trophic level -in ecosystems, each level of energy storage which is also a food supply for the next.
Tropic -a line of latitude marking the most northerly and most southerly overhead paths of the sun. On June 21st the track is in the north and is marked by the Tropic of Cancer. On December 21st the track is in the south and is marked by the Tropic of Capricorn.
Tropical -of the tropics, commonly relating to areas between them.
Tropical cyclone -a severe low pressure weather system which develops over tropical maritime areas. A steep pressure gradient and the central uplift draws in high speed winds which spiral towards the central area. Uplift causes cooling to the dew point, releasing latent heat and maintaining the uplift, drawing in fresh winds. Brings heavy rainfall to coastal areas. At the end of summer, can develop into larger, more severe systems such as typhoons and hurricanes.
Tropical rainforest - a forest biome located approximately 5˚N and S of the equator. Characterized by high annual rainfall >2000mm and high average annual temperature >25˚C. Thus, along with the vegetation being evergreen, it has the highest rate of net primary productivity of any biome.
Tropopause -a narrow layer of the atmosphere between the troposphere and the stratosphere. Varies between altitudes of 8km above the poles to 16km above the equator. Marks the limit of weather.
Trough - 1)
In geology, a trough generally
refers to a linear structural depression that extends
laterally over a distance, while being less steep than a
trench. 2) In
metrology, an elongated region of relatively low atmospheric
pressure, often associated with fronts.
Truncated spur -steep cliff face at the side of a glacial trough where a valley glacier has removed an interlocking spur. The glacier is unable to follow the winding course of the original river and ulldozes-straight through.
Tsunami -a large wave, or series of waves, caused when an earthquake causes massive undersea crust movements and/or collapses which displace the water above.
Tundra -the biome found in the Arctic circle across North America, Greenland and Europe. Winters are long and cold and in summer the daytime temperature rarely exceeds 5˚C. Precipitation is low and mostly falls as snow. Vegetation is mostly grasses, mosses and lichens with occasional small trees in more sheltered areas.
Turbine -a rotary motor driven by a flow of water, steam or wind to produce electrical energy.
Twilight zone -in Burgess model of urban land use, the second zone, surrounding the CBD characterized by old factories and slum areas which may be in transition and experiencing some regeneration.
Map out your future - but do it in pencil. The road ahead is as long as you make it. Make it worth the trip.
Jon Bon Jovi