glaciation

energy from the sun, precipitation, rock debris

meltwater, sediment deposition

erosion and transportation processes, which move ice and rock around the system

changes in accumulation and ablation do not vary much from the long-term average conditions

the glacier changes from one state of equilibrium to another due to an event causing a change in conditions

the state of equilibrium changes over a longer timescale than metastable equilibrium

increases the initial change: e.g increase in snoww cover --> more solar energy, reflected, creating cooler temperatures --> more snow

global warming increases evaporation and cloud cover --> more solar energy is reflected, creating cooler temperatures

elliptical orbit changes to more circular and back again over a 100,000 years, varying the amount of solar radiation reaching earth

varying from 21.8 to 24.4 over a period of 41,000 years, changing the amount of solar radiation at the poles

earth wobbles on its axis over a 20,000 year cycle, changing the time of year when it is closet to the sun

2.5 million - 11,500 years ago,

11,500 years ago to today, which is the present interglacial period

glacial oscillation between 1350 and 1850

• occur in high latitudes

• ice temperature below pressure melting point

• basal ice is frozen to bedrock

• most movement by internal deformation

• little erosion due to lack of movement

• occur in temperate regions

• temperature at base at pressure melting point

• heat from earth adds to melting

• meltwater assists movement of glacier

• actively eroding and transporting

cold-based in the upper region and warm-based lower down

the downslope force due to gravity resulting from the build-up of an ice mass

intergranular flow - under pressure the ice crystals move relative to each other

laminar flow - ice crystals move along parallel layers within the glacier

enhanced basal creep - basal ice deforms around irregularities in the bedrock surface

regelation slip - basal ice deforms under pressure caused by obstacles; once past the obstacle the meltwater refreezes

softer rock and unconsolidated sediments are not strong, so the weight of the ice in a glacier can cause the sediments to deform. As the sediments change shape, the ice on top moves with them

a reduction in gradient results in a slowing of movement. The ice thickens, crevasses close and thrust faults develop in the ice

an increase in gradient results in accelerated movement. The ice thins and crevasses form

an ice dome, several kilometres thick, submerging the topography beneath

a large area of floating glacier ice extending from the coast

a smaller version of an ice sheet covering an upland area

ice covering an upland area, but not burying topography

a glacier confined between valley sides

a valley glacier that fans out over a flatter area at the end of the valley

a small glacier filling a hollow on the side of a mountain

today - 10% of earth's land area 85% of all glaciers are in Antarctica

repeated freezing and thawing of water, expanding cracks in rocks and eventually causing fragments to break off and fall on to the glacier

debris embedded in the glacier base scrapes the bedrock as it moves

ice freezing on to valley sides, floor and bedrock pulls away rocks as it moves

meltwater flowing at the base of a glacier erodes rock the same way as surface streams. Pressure causes streams to flow faster, increasing erosion potential

• basal thermal regime

• ice velocity

• ice thickness

• bedrock permeability

• bedrock jointing

• debris characteristics

debris from weathering falls from valley sides onto the glacier

debris falls into crevasses and is moved within the glacier

basal ice freezes around material and drags it along by traction. Englacial material moving to the base and plucking adds to the amount

unsorted, angular material deposited by melting ice. Stones show no preferred orientation

rounded, subglacial material deposited by a moving glacier. The long axis of stones is orientated in the direction of movement

weak bedrock is deformed by ice movement

a high ridge across a valley deposited as a glacier retreats from the furthest point reached

a series of ridges across a valley behind a terminal moraine, marking a stationary period in ice retreat

weathered material falls on to a glacier from valley sides. When the ice melts it deposits a ridge parallel to the valley sides

two lateral moraines combine along the centre of glacier surface when valley glaciers merge. As ice melts it is deposited along the middle of the valley

when glaciers begin advancing again, the debris at the snout is pushed into a ridge

subglacial streams are under pressure and fast flowing, eroding bedrock especially by abrasion

high-energy meltwater streams have the capacity to transport large sediment loads

when I loses energy it deposits material; rounder than glacial deposits, sorted by size, distinct layers

the edges of glacial areas, where repeated freezing and thawing modify the landscape

soil and rock that is below O degrees celsius for at least 2 years

a.layer of frozen ground that can be hundreds of metres deep

a thinner, fragmented layer of frozen ground

an isolated mass of permafrost in unfrozen ground

the surface layer up to 3m deep, which thaws in summer and refreezes during the winter

a dome-shaped mound of earth up to 70m high and 500m in diameter, with an ice core

the downward movement of materials due to gravity

rockfalls and landslides change the profile fo a glacial valley

volcanic activity causes large-scale melting, resulting in flooding and rapid mudflows

Helvellyn range

red tarn

Ullswater valley

Ullswater

Norfolk island

Walla crag

8 countries

• France

• Switzerland

• Liechtenstein

• Italy

• Slovenia

• Austria

• Germany

• Monaco

• mountain farming

• energy

• mountain forests

• conservation of nature + countryside

• Transport

• Tourism

• soil conservation

• spacial planning and sustainable development

• largest protected area in alps

• Grossglockner glacier --> 3000m

• 4000 types of fungi

• 20,000 animal species

• donation of land use footpaths well maintained

• Gardonna Mountain Resort --> eco hotel

• public transport = free

• protection of ski areas --> cow's graze in summer

glacial lake outburst flood

affects fresh water, agriculture, livelihood

• increase in depth due to melting ice caused moraine dam to break

• village flooded 7 hours after dam break

• 2m deep, 200km away from source