Physical Characteristics of Cold Environments
Polar
- Climate
- Harsh, covered in snow and ice
- Long winters and short summers
- Snow storms and cold winds for most of the year
- The Arctic's mean temperature range is -28°C to 4°C
- Average annual precipitation of approx. 100mm
- The Antarctic's mean temperature is -55°C in places
- Coastal areas are milder with an annual average of -10°C
- Annual average precipitation is 200mm
- Soil
- Where land is ice-free, the soil is thin, acidic and infertile
- Lacks nitrogen and carbon due to low decomposition rates
- Vegetation
- Limited liquid water slows growth and species diversity
- Mosses and lichens are able to survive in some areas
- The roots of these plants secrete an acid that dissolves rock
- In this way, they gain nutrients from the rock they are attached to
Alpine
- Climate
- Cool climates with some snow coverage but not all year
- Seasonal temperatures range from −10°C in winter to 20°C in the summer months
- Precipitation in alpine mountains depends on aspect
- Windward sides receive large amounts of precipitation; with snow in the winter months
- Leeward sides are in the rain shadow and therefore, drier and protected from strong winds
- Soil
- Where land is ice-free, soil is thin, acidic, gravelly and infertile
- Lacks nitrogen and carbon due to low decomposition rates
- Vegetation
- Lack of liquid water limits growth and species diversity
- Low-lying shrubs and mosses and lichens thrive at the highest altitude
Glacial
- Climate
- Characterised by permanently low temperatures, but may rise above 0°C with seasonal temperature variations
- Cold climates in high latitudes and altitude
- Ice remains throughout the year
- High precipitation, but limited liquid precipitation, provides inputs into the glacial system
- Little seasonal temperature variation
- Soil
- Glacial soil is rocky, and thin, with ice blocks and infertile
- The soil exposure is less due to snow cover
- Vegetation
- Limited growth and species diversity due to ice and snow cover and lack of liquid water
- Mostly mosses and lichens
Periglacial
- Climate
- Cool climates with some snow coverage but not all year
- Seasonal temperatures range from −10°C in winter to 20°C in the summer months
- Mean average temperature between -1°C and -3°C
- Precipitation in alpine mountains depend on aspect
- Windward sides receive large amounts of precipitation; with snow in winter months
- Leeward sides are in the rain shadow and therefore, drier and protected from strong winds
- Mean annual precipitation less than 1000mm
- Soil
- Most of the soil is permafrost with some regions seeing seasonal melting creating an 'active layer' for growth
- Where there is seasonal melting, the soils become deeper with peaty, un-decomposed vegetation and frost-shattered rock
- They are a good source of carbon and methane sequestering
- The potential of these soils is significant in forecasting global temperatures in the future
- Occasionally, unfrozen soil is found within the permafrost called talik
- Talik is thought to form when latent heat is released as the active layer re-freezes
- Vegetation
- Limited growth and species diversity due to permafrost and intermittent liquid water
- Mosses, lichens and small shrubs of birch and willow
- Where meltwater is available and soil depth sufficient, growth and species diversity increases
- Low-growing plants have small, waxy leaves designed to retain warmth and reduce transpiration through wind exposure
- During the short summer months, they flower and set seed in just a few weeks and are brightly coloured to attract as many insects as possible
