Introduction
Glaciers are natural systems because they are an assembly of interrelated parts that work together by way of driving processes. They have inputs and outputs of energy and material, and involve a flow of energy which goes beyond the boundary of the system out into the surrounding environment. This makes the glacier system an open system.
This resource will focus on how this glacial system is changing in the Alps, where glaciers are displaying negative mass balance, and what this means for cold environments. In particular, mountainous ones.
The term 'cold environments' covers four classifications: polar and alpine settings where glacial and/or periglacial conditions are dominant. Environmental descriptions are listed below.
Environments
Polar environments
Polar environments have extreme climates and are very cold. They include both the Arctic and Antarctic, which both contain the world’s coldest deserts, and are characterised by very low rates of snowfall. In past climates, around 115,000-25,000 years ago, when polar conditions extended to lower latitudes, ice sheets built up over North America (as the Laurentide Ice Sheet) and North Europe (over the UK, Norway and Sweden as FennoScandian Ice Sheet).
Alpine environments
Alpine environments are high elevation regions around the world. They are often cold, windy, and snowy, and are characterised by a very short frost-free period. They receive high seasonal snowfall with a cold winter and a warm summer season. Areas include the European Alps, the Andes, the Rocky Mountains, New Zealand's Southern Alps and the Himalaya. The Alpine biome usual lies between 3,000 meters and the place where the snow line of a mountain begins.
Conditions
Glacial conditions
Glacial conditions describe perennial accumulation of snow on land, which is compressed into ice, and then moved downslope under the influence of its own weight. As the glacier moves it erodes the landscape.
Periglacial conditions
Periglacial environments are usually areas with a cold climate, with permafrost in some form often being present. They typically occur near glacierised regions. Periglacial processes, such as weathering, mass movement, ground ice formation and erosion all contribute to the formation of periglacial landforms; blockfields, ice wedges, patterned ground, pingos, solifluction lobes, terracettes, and thermokarsts.
