Spatial Distribution of Glaciers

Current glacierization
Areal Extent of Glaciers

Flint: - Importance of knowledge of Glacier Volumns – appreciate the importance of glacierization

Glacier volume – by radio-echo sounding
Degree of Inundation of land surface by snow & ice
Degree of Glacierization – percentage of land surface covered at the end of Balance
Year,
Data Plotted on a grid instead of a map
Degree of relief by ice
- Morphological variable within a landscape system
- Index of the intensity or type of glacial or nival processes operating upon the bedrock base

Detailed movement of snow & ice thickness – radio echo sounding profile
Continuous data concerning ice surface altitude & form, ice thickness, sub-ice bedrock relief
Applied in Greenland, Arctic Canada & Antarctica

Factors influencing the current distribution of snow & ice
Precipitation
High Evaporation rate, low annual precipitation, negative net precipitation
High altitude west coast environment – extremely heavy precipitation
Glaciologically influence as precipitation in the form of rainfall – contributes little to glacier mass

Nivometric coefficient – index of snow effectiveness
- ratio of snowfall (in water equivalent) to total annual precipitation

Nivometric coefficient – > 1 low precipitation
less suitable for glacial growth suitable for prolonged glacial survival

Medium Nivometric coefficient – high precipitation
Marginal from point of view of glacierization

Nivometric coefficient < 1 – high precipitation

Temperature
Mean summer temperature
Relationship between regional temperature characteristics & glaciarization

Latitute
Ice cover zone
Frost rubble zone climatically contolled systems
Tundra Zone



Altitude
Independent parameter at regional & local scale. Fundamental control over climatic parameters & hence on glacier distribution
Altitudinal zonation of mountainous area
Glacial/ Nival
Sub nival
Alpine
Sub Alpine
Upto sea level in high laltitude
High altitude in low latitude

Relief
Surface relief
Breath of an individual summit determines whether or not a glacier can be supported
Glaciation level
Partsch – brucker method of defining this limit

Snow fence effect – jaggered mountain scenary in baffin island in trapping snow &
allowing cirque glacier to develop lower than normal altitudes
mass balance – position of snout
morphology of channel – precise location of channel

shape ratio: ratio of elevation to area – and over 600m
roughness index: geometric properties of surface
high dissected topography – inhibit glacierization

Aspect
Orientation of ground surface with respect to incoming solar radiation (local scale)
Little control at regional/ larger scales

Distance from nearest ocean
Independent variable – influencing
Regression analysis

Glacier Inertia
Ice caps & ice sheets – out of equilibrium with their climatic environment devoid of relationship between morphological parameters as altitude, aspect & relief













Regression graphs are used to pot relationships – eg . Between altitude of glaciations level for Norway & ocean distance – Chorlton & lister