GLACIER WEBSITES

http://www.research-projects.uzh.ch/p11850.htm

http://omega.utu.fi/publications.html

http://www.nps.gov/archive/mora/ncrd/glacier/Res00.html#2

http://www.nichols.edu/departments/glacier/

http://www.glaciologia.cl/

GLACIER ICE FLOW

INTERNAL DEFORMATION

o Deform internally under the influence of gravity
o Glacier ice is aniosotrophic, with lattice defects, slippage of planes of atoms

BASAL SLIP

o Ice at pressure melting point
o Ice mass slips over a thin layer of meltwater
o Not continuous
o Reduction of pressure melting point effectively refreezing & immobility
o Localized grounding due to water removal by freezing or drainage
o Regelation and enhanced creep

BOOKS

1. Field Techniques in Glaciology and Glacial Geomorphology - Bryn Hubbard Neil Glasser
2. Glacial Geomorphology - Michael Hambrey
3. Glacial & Perglacial Geomorphology - Embleton & King
4. Glaciers and Environmental Change - Atle Nesje and Svein Olaf Dahl
   
5. Glacial Landsystems - David J.A. Evans
   

1. Schytt – described the overall purpose of glacier mapping
2. Blachut & miller – Some problems & solutions in constructing glacier maps using examples of
White glacier in the Canadian Arctic
Solomon Glacier in Rocky Mountains
Khumbu Glacier in Himalayas
3. Demek & embleton, Gardiner & Dacombe – various approaches use in geomorphological mapping
4. Waters – techniques used in morphological mapping
5. A Goudie – Geomorphological Techniques
6. A Pench – Glacial Feature on the surface of alps
7. J.Tricart – Geomorphology of cold Environments
8. Lewis A.Owen, David J.Evans, Jim Hansom – Arctic & Alpine Geeomorphology
9. Parsons & knight – Research planning for glacier Mapping, glaciological map
10. Ian Evans – Measurement & interpretation of Assymetry in Glaciated mountains
11. R.J. Chorley – The shape of Drumlins
12. Field techniques in Glaciology & Glacial Geomorphology – Bryn Hubbard & Neil Glabber
13. Ostrem G. & brugman M – Glacier Mass Balance measurement – a manual for fieldwork & officework
14. Armstrong – Illustrated glossary of snow & ice

TERMINOLOGIES RELATED TO GLACIERS

• ABLATION – all forms by which snow is lost from glacier – by evaporation & melting
  

• ABLATION AREA – area where snowfall is less than snow ablation, demarcated from accumulation by firnline
  

• ACCUMULATION AREA – area where snow accumulates
  

• ALBEDO – percentage of sun’s radiation reflected off
  

• CIRQUE – deep, steep-walled recess in mountain, glacial erosion
  

• CREVASSES – fissures in glacial ice, variable speed of ice
  

• EQUILIBRIUM LINE – demarcation between accumulation and ablation area
  

• ERRACTIC – rock of unspecified size or shape, transported by glacier
  

• FIRN – old snow recrystallized into more dense substance
  

• FIRNLINE – above firnline glacier ice, is converted from snow as air is forced out
  

• GLACIAL ADVANCE – Net Movement of Glacier terminus down valley
  

• GLACIAL DRIFT – loose & unsorted rock debris distributed by glacier & glacial meltwaters
  

• GLACIAL FLOUR – fine-grained sediments carried by glacial rivers
  

• GLACIAL RETREAT – net movement of glacier upvalley when ablation exceeds accumulaton
  

• GLACIAL TILL – an unsorted unstratified mixture of time & coarse rock debris
  

• GLACIER CAVE – steam or high heat flow
  

• GLACIER ICE – snowflakes composed by weight of overlying snowpack
  

• GLACIER MORAINE – deposition feature
  

• GLACIER SNOUT – terminus of glacier
  

• ICEFALL – analogous to waterfall
  

• JOKULHLAUP – sudden outbursts of water from glaciers
  

• LAHAR – Mudflow or debrisflow originating in river
  

• LATERAL MORAINE – Piles of loose unsorted rocks along side margins of glacier
  

• MASS BALANCE – net gain or loss of snow
  

• MEDIAL MORAINE – moraine formed by convergence of two lateral moraines
  

• NEOGLACIATION – advances made by mountain glaciers in Great Pleistocene Ice age
  

• OGIVES – Arc shaped features across glacier surface below icefall
  

• ROCHE MOUTONNEES – small asymmetric hill of glacial erosion
  

• ROCKFLOUR – Glacier Flour
  

• ROCK GLACIER – Glacier like landform
  

• SERACS – pinnacles of ice where glacier surface is torn by crevasses
  

• STRIATIONS – scratches on rock surface
  

• SUNCUP – Small Depression on snow or firn
  

• SURGE – short-lived frequently large scale increase in rate of movement of ice within a glacier
  

• TARN – lakes developed on the basis of a cirque
  

• TERMINAL MORAINES – piles of loose unconsolidated rock at glacier lowerend
  

• TERMINUS – downvalley end of glacier
  

• TILL – unsorted rock debris
  

• TRIMLINE – sharp vegetative margindemarking the upper margin of a former glaciation
  

• TUYA – volcano exploded under a glacier U-shaped valley

CLASSIFICATION OF GLACIERS

CLASSIFICATION

• Morphological Classification – based on form and size of ice
• Dynamic classification – based on degree of activity of ice
• Thermal classification
  

THERMAL CLASSIFICATION

1. Temperate Glacier (warm)

o At pressure melting point throughout thickness except winter when uppermost layer is temporarily colder
o Glaciers of Alps and Southern Scandanevia
o Meltwater exists at its bed so flows fairly easily
o Rapid rate of firnification
o Summer melting both in accumulation and ablation zone

2. Cold or Polar Glacier

o Subpolar type – surface melt and water present
o High polar type – temperature of firn below freezing point, no melting in summer
o Geomorphologically no basal meltwater

DYNAMIC CLASSIFICATION

Active
Passive
Dead Glaciers

1. Active Glaciers
   

• Fed by continuous ice stream from an accumulation zone in a cirque basin or a plateau
• Subgroup – regenerated type – fed by ice avalanches falling from upper accumulation area to lower ground
• Outlet Glacier – fed by avalanches at Morsarjokull in Iceland
• Active glaciers have net total budget, does not depend on positive or negative budget
  

2. Dead Glaciers
   

o Not necessarily immobile
o Does not receive ice from an accumulation area
o Low ground where flow induced by slope is low
o Vale of Belvoir, Norrland in Sweden

MORPHOLOGICAL CLASSIFICATION

1. Niche, wall-sided or cliff glacier

• Triangular wedge of ice, slightly convex surface lying in a shallow funnel shaped hollow
• On steep slopes
• Gully runs from the glacier lower end to the alluvial fan below
• Spitsbergen

2. Cirque Glacier
• Jotunheim, Norway
• Vesl-Skautbreen
  

3. Valley Glacier - Alpine type

o Snowline falling in elevation, ice of cirque can move out of basin and down the valley to form a valley glacier
o Several cirques combimes to form valley glacier
o Alhamann’s divison – 4 types

i. Rhone Glacier or Hintereisfermer – Considerable portion above their median height
ii. Grosser Aletschgletscher – High Level neve Basin, Greatest part occurs in Upper part of Glacier Basin
iii. Glaciers that have most of their area at lowlevels and are fed by avalanches from higher snowfields – glaciers of Central asia, Styggedalsbreen, Norway
iv. Greater portion of their area a little below mean elevation – Spitsbergen

4. Valley Glacier – Outlet type

o Iceland – Norway
o Fed by ice cap, not by cirques
o Wider and flow with considerable rapidilty on steep slopes

5. Transection Glacier

o Lowenskjold glacier
o Occupy much of a mountain group from which glaciers flow in several directions into a system of radiating valleys
o Transfluent glacial breaches and cols

6. Piedmont Glacier

o Malaspina Glacier, Skeioararjokull, Vatnajokull
o Valley Glacier advances out from the containing mountain walls into lowland beyond

7. Floating ice tongue & ice shelves

o Floating Ice Tongues - Restricted to high latitude where glaciers reach the sea, Steensby Gletscher in Northe Greenland, Petermanns Gletscher, Ryder Gletscher
o Ice Shelves – characteristics of Arctic Rosss Ice Shelf

8. Mountain Ice cap

o Vatnajokull in Iceland, Jostedalsbreen in Norway
o Accumulation area from where outlet glaciers flow

9. Glacier Cap or Lowland ice-cap

o Arctic regions of northern Canada, Barnes Ice Cap
o Ice masses in Lowland

10. Ice-sheets

o Ice sheets