Unit 3 AOS1 Definitions Flashcards
Permafrost
A permanently frozen layer below the earth’s surface
Ice sheets
Vast masses of ice, domed in shape, not confined to valleys. Sometimes referred to as continental glaciers. Form in high latitude regions e.g. Antarctica and Greenland
Last Glacial Maximum (LGM)-
Most recent period in the earth’s history where glaciers were at their thickest and sea levels were at their lowest, roughly between 21,000 and 18,000 years ago.
Cryosphere
Components of the earth’s system at and below the land and ocean surface, that are frozen
Holocene Climactic Optimum
Warm period roughly during the interval between 9000 and 5000 BP with a thermal maximum around 8000 years BP
Tundra
Areas where tree growth is hindered by frigid temperatures and short growing seasons
Peri-glacial zones
Marginal to the glacial environment
Ablation
The process of melting ice on glaciers
Accumulation
Annual snowfall and ice which builds up over time and doe not entirely melt during the summertime
Terminus
Where glacial ice starts to melt
Equilibrium line
Where ablation and accumulation are equal
Glacial Mass balance
Gain and loss of ice from the glacial system. Glaciers are the product of how much mass it receives and how much it loses by melting
Land cover
The observed biophysical cover on the earth’s surface
Land use
How people use areas of land characterised by arrangements, activities and inputs people undertake in a certain land cover type to produce change or maintain it
Cryoconite
A grey to black coloured mineral composed of windblown sediments such as soot, dust or soil
Dark ice
Speeds up the melting process. Less reflection of heat due to darker colours
Moulin
A vertical cylindrical shaft in the ice by which surface meltwater flows down from the surface to the base of the glacier or the ice sheet
Glacial Lake Outburst Flood (GLOFs)
Glacial lakes that appear in natural landscape depressions downstream of the terminus with huge increases in the rate of flow and volume of meltwater cause lakes to break dam and flood further downstream.
Geospatial technology
Digital tools for geographic inquiry that include hardware and software interacting with real world locations. Any form of technology that organises and collects data that is referenced to a point on the earth’s surface via latitude and longitude.
GNSS
24 satellites that circle the earth, can determine a user’s exact position in terms of latitude, longitude and altitude of the users position.
GIS
Computer based mapping software that collects, stores and analyses previously unrelated information, represented as layers on a map that can be turned on or off
Remote sensing
Obtains information about the earth’s surface without being in contact with it, Passive sensors responding to external stimuli or active sensors responding to internal stimuli. Data collected by aircraft, satellite or aerial photos
The interconnection between land cover/use
Land use is characterised by the actions, arrangements and inputs people undertake in a certain land cover type to change or maintain it e.g. in a grasslands area, the grassland is land cover and is grazing took place there that would be its land use.
Cultivated and managed
People must have removed vegetation and replaced it with another type, Land cleared of trees/scrub and food crops are planted
