Tundra
Tundra environments are basically cold deserts. The three types of tundra are: Arctic tundra, Antarctic tundra and Alpine tundra.
Features of tundra:
Features of tundra:
- Tree growth hindered by low temperatures and short growing seasons
- Dominant vegetation is grasses, mosses and lichens
- The ecotone between tundra and the forest is known as the tree-line of timberline.
- Biodiversity of tundra is low
- Summers are short and moisture is scarce.
Tundra Glossary
Albedo: The fraction of of solar radiation that is reflected back into space.
Antarctic Circle: The parallel of 66.5 degrees south latitude.
Arctic Circle: The parallel of 66.5 degrees north latitude.
Atmosphere: The gaseous envelope surrounding Earth.
Biosphere: The living organisms of Earth.
Boreal forest (taiga): a needle-leaf forest in sub-arctic regions of Eurasia and North America.
Carrying capacity: In the case of tourism, carrying capacity refers to the number of visitors or activities that can take place in an area without environmental degradation occurring.
Climate: Weather conditions of a long period of time.
Evaporation: When liquid water is converted to gaseous water vapour.
Glacier: a large natural accumulation of land ice that flows downhill, or outwards from the it point of accumulation.
Hydrosphere: All water on Earth, including lakes, rivers, oceans, groundwater, etc.
Ice Sheet: A blanket of ice that completely covers the underlying terrain.
Lithosphere: the solid, inorganic portion of the Earth's surface.
Polar High: A high pressure system over either polar region.
Subpolar Low: A zone of low pressure situated at about 50-60 degrees latitude (either North or South). Also known as a polar front.
Taiga: see boreal forest.
Tundra: a treeless region, where low growing plants such as moss, heath and lichens grow and where subsoil is permafrost or permanently frozen soil.
Permafrost: permanently frozen, impermeable ground (upper layers may thaw during summer). It results when ground surface temperatures remain below freezing point for long periods.
Weather: short-term atmospheric conditions (day-to-day).
Antarctic Circle: The parallel of 66.5 degrees south latitude.
Arctic Circle: The parallel of 66.5 degrees north latitude.
Atmosphere: The gaseous envelope surrounding Earth.
Biosphere: The living organisms of Earth.
Boreal forest (taiga): a needle-leaf forest in sub-arctic regions of Eurasia and North America.
Carrying capacity: In the case of tourism, carrying capacity refers to the number of visitors or activities that can take place in an area without environmental degradation occurring.
Climate: Weather conditions of a long period of time.
Evaporation: When liquid water is converted to gaseous water vapour.
Glacier: a large natural accumulation of land ice that flows downhill, or outwards from the it point of accumulation.
Hydrosphere: All water on Earth, including lakes, rivers, oceans, groundwater, etc.
Ice Sheet: A blanket of ice that completely covers the underlying terrain.
Lithosphere: the solid, inorganic portion of the Earth's surface.
Polar High: A high pressure system over either polar region.
Subpolar Low: A zone of low pressure situated at about 50-60 degrees latitude (either North or South). Also known as a polar front.
Taiga: see boreal forest.
Tundra: a treeless region, where low growing plants such as moss, heath and lichens grow and where subsoil is permafrost or permanently frozen soil.
Permafrost: permanently frozen, impermeable ground (upper layers may thaw during summer). It results when ground surface temperatures remain below freezing point for long periods.
Weather: short-term atmospheric conditions (day-to-day).
Tundra - Biophysical Processes
Pre-lesson activity
Refer to an atlas, and examine world maps showing patterns of:
- World Biomes
- Climatic zones
- Soil types
Describe the location of tundra environments globally?
What climatic zones correlate with the location of tundra environments?
What soil types correspond with the location of tundra environments?
Describe the location of tundra environments in relation to latitude.
Further reading:
Tundra characteristics
Tundra facts and information
The tundra biome
Arctic tundra
Blue Planet Biomes - Tundra
Latitude and Altitude
Tundra occurs only in perennially cold climates of high latitude (Arctic and Antarctic tundra) and high altitudes (Alpine tundra).
High latitude refers to locations furthest away from the Equator, and closest to the poles. Arctic and Antarctic tundra usually refers to locations about 60 degrees latitude. The extreme cold temperatures and permafrost inhibit tree growth. The arctic and antarctic tree line can vary based on a range of climate and topographic features so 60 degrees latitude is indicative only.
Alpine tundra is is affected by altitude, and associated climate. Altitude (height above sea level) impacts on types of vegetation that can survive. The alpine tree line marks the location above which trees can no longer survive. This is due to a number of factors such a tree sap freezing, excessive snow, decreasing air temperature, and shortened growing periods.
Refer to an atlas, and examine world maps showing patterns of:
- World Biomes
- Climatic zones
- Soil types
Describe the location of tundra environments globally?
What climatic zones correlate with the location of tundra environments?
What soil types correspond with the location of tundra environments?
Describe the location of tundra environments in relation to latitude.
Further reading:
Tundra characteristics
Tundra facts and information
The tundra biome
Arctic tundra
Blue Planet Biomes - Tundra
Latitude and Altitude
Tundra occurs only in perennially cold climates of high latitude (Arctic and Antarctic tundra) and high altitudes (Alpine tundra).
High latitude refers to locations furthest away from the Equator, and closest to the poles. Arctic and Antarctic tundra usually refers to locations about 60 degrees latitude. The extreme cold temperatures and permafrost inhibit tree growth. The arctic and antarctic tree line can vary based on a range of climate and topographic features so 60 degrees latitude is indicative only.
Alpine tundra is is affected by altitude, and associated climate. Altitude (height above sea level) impacts on types of vegetation that can survive. The alpine tree line marks the location above which trees can no longer survive. This is due to a number of factors such a tree sap freezing, excessive snow, decreasing air temperature, and shortened growing periods.
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Atmospheric processes
Climate
The Tundra Climate zone refers to the climate of high-latitude region between 60-75 degrees latitude. Using the Koppen Scheme it is known as ET. E refers to locations with no month with average temperatures above 10 degrees celsius. T refers to locations with at least 1 month with average temperatures between 0-10 degrees celsius. Characteristics include long, cold, dark winters, and brief, cool summers.
Temperature
In Tundra climates there are only 1-4 months when average temperatures are above freezing. The average winter temperature is -34 degrees celsius, and the average summer temperature is 3-12 degrees celsius. Annual temperature ranges are fairly large, and mean annual temperatures are sub-freezing. Daily temperature ranges are small because nocturnal cooling is limited in summer due to the sun being above the horizon for most of the time. In winter, daytime warming is almost nonexistent.
Precipitation
Precipitation is very sparse and there is a moderately low annual precipitation (less than 25cm annually). More rain falls in the warm season than in winter and most precipitation that is received is in the form of snow. Winter snow is dry and granular and there is little/no melting of snow.
Humidity
Moisture availability is restricted. Air is too cold to hold much water. Humidity is always very low.
Radiation fog
Radiation fog is common. It is a type of fog that forms overnight as the air near the ground cools, stabilises and reaches saturation point. Radiation fog will begin to form near the surface and then thickens as the air continues to cool.
Read more about the tundra climate
Click to examine the Climate Atlas of Canada.
Hydrospheric processes
Transpiration
There is limited transpiration due to the limited amount of vegetation.
Evaporation
Surface and soil water is frozen for most of the year so there is little evaporation and low stores of water in the atmosphere.
Precipitation
There is a low annual precipitation - mainly in the form of snow.
Groundwater
In summer, meltwater forms many wetland areas, ponds and lakes. The water in the uppermost layer of permafrost melts in spring and summer.
Infiltration
Permafrost is a barrier to infiltration and percolation.
Water storage
Accumulation of snow and river and lake ice during winter.
River flow increases when snow, ricer and lake ice melts.
Lithospheric processes
Bedrock and soils impact on the stability of the ground to build on, and the types of vegetation and fauna present. Permafrost is any ground (soils, rocks, etc) that remains frozen for at least two years straight. Permafrost is common in high latitudes and high altitudes. For more information visit What is permafrost?
The permafrost and crystalinne rocks mean that tundra soils tend to be quite impermeable. This means that they don't allow water to infiltrate, or drain away. As a result during summer months when snow and ice has melted, lakes, and wetlands form, and soils are waterlogged.
During the growing seasons (spring and summer), plants put carbon-rich litter into the soil. This will be made up of dead leaves, sticks, etc. Animal droppings will also contribute to the soils. The litter will decompose, but because of the low temperatures the decomposition will be much slower than in many other ecosystems. Permafrost is a vast store of carbon.
Snow covers large sections of the ground for much of the year. The cold temperatures make it difficult for microbiotic organisms to breakdown organic material. However, it is thought that snow cover may actually provide insulation in some areas for microbiotic organisms to allow some decomposition despite the low temperatures.
Erosion is the wearing away of materials (soils, rocks, etc) by natural forces such as wind and water. Weathering is when materials (soils, rocks, etc) or broken down or dissolved by environmental factors. There are three types of weathering: physical, chemical and biological. Arctic tundra is particularly affected by strong winds and the erosion caused by it. The removal of this fragile soil is influenced by the limited vegetation in tundra environments. The long term effect of erosion and weathering on arctic tundra has resulted in predominantly low, flat relief. Most tundra environments have not been as affected by weathering as many other environments. Around 9,000-11,000 years ago most tundra environments will still covered by glaciers.
For more details read Wind Erosion and Arctic Tundra: Carbon Effects.
Glaciation has shaped the landscape. Processes of abrasion, plucking and freeze-thaw weathering have created the landforms in many arctic tundra environments. Abrasion is when rocks that have been frozen into the base and side of a glacier scrape along bedrock as the glacier moves downslope. This leaves scratched in the bedrock called striations. Plucking occurs when rocks become frozen into the glacier and as the glacier moves it picks up the rocks and moves them to another location. These rocks are then deposited randomly. Freeze-thaw weathering occurs when ice melts, fills cracks in the rocks and then expands when it refreezes. To learn more about glacial landforms explore Bitesize: Glacial processes and landforms.
Climate
The Tundra Climate zone refers to the climate of high-latitude region between 60-75 degrees latitude. Using the Koppen Scheme it is known as ET. E refers to locations with no month with average temperatures above 10 degrees celsius. T refers to locations with at least 1 month with average temperatures between 0-10 degrees celsius. Characteristics include long, cold, dark winters, and brief, cool summers.
Temperature
In Tundra climates there are only 1-4 months when average temperatures are above freezing. The average winter temperature is -34 degrees celsius, and the average summer temperature is 3-12 degrees celsius. Annual temperature ranges are fairly large, and mean annual temperatures are sub-freezing. Daily temperature ranges are small because nocturnal cooling is limited in summer due to the sun being above the horizon for most of the time. In winter, daytime warming is almost nonexistent.
Precipitation
Precipitation is very sparse and there is a moderately low annual precipitation (less than 25cm annually). More rain falls in the warm season than in winter and most precipitation that is received is in the form of snow. Winter snow is dry and granular and there is little/no melting of snow.
Humidity
Moisture availability is restricted. Air is too cold to hold much water. Humidity is always very low.
Radiation fog
Radiation fog is common. It is a type of fog that forms overnight as the air near the ground cools, stabilises and reaches saturation point. Radiation fog will begin to form near the surface and then thickens as the air continues to cool.
Read more about the tundra climate
Click to examine the Climate Atlas of Canada.
Hydrospheric processes
Transpiration
There is limited transpiration due to the limited amount of vegetation.
Evaporation
Surface and soil water is frozen for most of the year so there is little evaporation and low stores of water in the atmosphere.
Precipitation
There is a low annual precipitation - mainly in the form of snow.
Groundwater
In summer, meltwater forms many wetland areas, ponds and lakes. The water in the uppermost layer of permafrost melts in spring and summer.
Infiltration
Permafrost is a barrier to infiltration and percolation.
Water storage
Accumulation of snow and river and lake ice during winter.
River flow increases when snow, ricer and lake ice melts.
Lithospheric processes
Bedrock and soils impact on the stability of the ground to build on, and the types of vegetation and fauna present. Permafrost is any ground (soils, rocks, etc) that remains frozen for at least two years straight. Permafrost is common in high latitudes and high altitudes. For more information visit What is permafrost?
The permafrost and crystalinne rocks mean that tundra soils tend to be quite impermeable. This means that they don't allow water to infiltrate, or drain away. As a result during summer months when snow and ice has melted, lakes, and wetlands form, and soils are waterlogged.
During the growing seasons (spring and summer), plants put carbon-rich litter into the soil. This will be made up of dead leaves, sticks, etc. Animal droppings will also contribute to the soils. The litter will decompose, but because of the low temperatures the decomposition will be much slower than in many other ecosystems. Permafrost is a vast store of carbon.
Snow covers large sections of the ground for much of the year. The cold temperatures make it difficult for microbiotic organisms to breakdown organic material. However, it is thought that snow cover may actually provide insulation in some areas for microbiotic organisms to allow some decomposition despite the low temperatures.
Erosion is the wearing away of materials (soils, rocks, etc) by natural forces such as wind and water. Weathering is when materials (soils, rocks, etc) or broken down or dissolved by environmental factors. There are three types of weathering: physical, chemical and biological. Arctic tundra is particularly affected by strong winds and the erosion caused by it. The removal of this fragile soil is influenced by the limited vegetation in tundra environments. The long term effect of erosion and weathering on arctic tundra has resulted in predominantly low, flat relief. Most tundra environments have not been as affected by weathering as many other environments. Around 9,000-11,000 years ago most tundra environments will still covered by glaciers.
For more details read Wind Erosion and Arctic Tundra: Carbon Effects.
Glaciation has shaped the landscape. Processes of abrasion, plucking and freeze-thaw weathering have created the landforms in many arctic tundra environments. Abrasion is when rocks that have been frozen into the base and side of a glacier scrape along bedrock as the glacier moves downslope. This leaves scratched in the bedrock called striations. Plucking occurs when rocks become frozen into the glacier and as the glacier moves it picks up the rocks and moves them to another location. These rocks are then deposited randomly. Freeze-thaw weathering occurs when ice melts, fills cracks in the rocks and then expands when it refreezes. To learn more about glacial landforms explore Bitesize: Glacial processes and landforms.
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Biospheric processes
Plants
Plants in tundra environments occur in ground-hugging, dense clumps. In some areas there is considerable bare ground. Tundra plants are a mix of low plants including dwarf shrubs, mosses, lichens, grasses, and forbs. No trees occur in tundra environments because the summer is so short that the conditions don't allow their growth. During the brief summer season, plants quickly complete their annual cycles. This is enabled by the moisture in the soil during this time.
Animals
Birds and insects (including mosquitoes and flies) dominate animal life in the tundra during summer. Insects eggs are able to survive the winter. Tundra becomes a an important site for nesting in summer, for birds migrating south in winter. While there are very few species of reptiles and amphibians, there are some species of mammals and freshwater fish.
Food chains and food webs
Read About Food Chains in the Tundra Ecosystem.
Plants
Plants in tundra environments occur in ground-hugging, dense clumps. In some areas there is considerable bare ground. Tundra plants are a mix of low plants including dwarf shrubs, mosses, lichens, grasses, and forbs. No trees occur in tundra environments because the summer is so short that the conditions don't allow their growth. During the brief summer season, plants quickly complete their annual cycles. This is enabled by the moisture in the soil during this time.
Animals
Birds and insects (including mosquitoes and flies) dominate animal life in the tundra during summer. Insects eggs are able to survive the winter. Tundra becomes a an important site for nesting in summer, for birds migrating south in winter. While there are very few species of reptiles and amphibians, there are some species of mammals and freshwater fish.
Food chains and food webs
Read About Food Chains in the Tundra Ecosystem.
Tundra - Causes of Change
Climate Change
A warming climate is drastically changing tundra environments. Glacial retreat and melting permafrost will have ongoing impacts and result in further change to the environment. Melting permafrost releases methane gas, which in turn will result in further melting. Higher temperatures will result in the growth of shrubs, changing the ecosystem and reducing the ability of soils to reflect heat.
Air pollution
Ozone depletion as a result of chemicals in aerosols have allowed stronger UV radiation to penetrate at the poles. Coal buring and industrial activity has resulted in toxic mercury in the atmosphere, accumulating in the Arctic. Air pollution can also affect the growth of lichen.
Industrial Activity Natural Resource Exploitation
Natural resource exploration and extraction can impact greatly on tundra environments. Activities can result in the thawing of permafrost, damage to soil and vegetation. There is also increased risk of toxic spills.
Development and Tourism
Human settlements and the construction of buildings and roads encroach on tundra environments and allow access for larger numbers of people to this fragile environment. Tourism operations such as buggy tours create roads and tracks through on the fragile permafrost and can disturb the normal behaviours of wildlife.
Introduced species
The introduction of plants and animals species can interrupt food chains and food webs, providing competition for endemic species.
Group work
In groups, examine the causes and extent of change to tundra environments globally. Present your findings in a report, including images, maps, and graphs. You will also need to provide a 2 minute presentation of your findings to the class.
A warming climate is drastically changing tundra environments. Glacial retreat and melting permafrost will have ongoing impacts and result in further change to the environment. Melting permafrost releases methane gas, which in turn will result in further melting. Higher temperatures will result in the growth of shrubs, changing the ecosystem and reducing the ability of soils to reflect heat.
Air pollution
Ozone depletion as a result of chemicals in aerosols have allowed stronger UV radiation to penetrate at the poles. Coal buring and industrial activity has resulted in toxic mercury in the atmosphere, accumulating in the Arctic. Air pollution can also affect the growth of lichen.
Industrial Activity Natural Resource Exploitation
Natural resource exploration and extraction can impact greatly on tundra environments. Activities can result in the thawing of permafrost, damage to soil and vegetation. There is also increased risk of toxic spills.
Development and Tourism
Human settlements and the construction of buildings and roads encroach on tundra environments and allow access for larger numbers of people to this fragile environment. Tourism operations such as buggy tours create roads and tracks through on the fragile permafrost and can disturb the normal behaviours of wildlife.
Introduced species
The introduction of plants and animals species can interrupt food chains and food webs, providing competition for endemic species.
Group work
In groups, examine the causes and extent of change to tundra environments globally. Present your findings in a report, including images, maps, and graphs. You will also need to provide a 2 minute presentation of your findings to the class.
Tundra Management
- Switching from fossil fuels to renewables
- Creating refuges
- Providing protection for individual species
- Limiting industrial activity
- Closely monitoring/limiting tourist activities
Read Bitesize: Strategies to minimise impact/effects
Tundra - Virtual Fieldwork
Fieldwork: Hudson Bay
Some schools may be able to do a field trip to Canada, however, for most schools if you use this case study, the best option would be to complete fieldwork on Environmental Change as a general topic in your local area, and complete virtual fieldwork on this case study. Below are some options to help you do this.
Observations
An important initial step in any fieldwork trip is observation. An observation helps provide the researcher with a broad view of the environment and can help frame initial research questions or provide general information about basic questions in your research.
Explore how the Google Maps team are helping build and share a Google Maps Tour of Churchill
Line drawing/Photosketch
Tools:
pen,
paper,
eraser,
ruler
Examine the scene and settle on a particular view
Draw a box (frame) for your sketch.
Draw a general outline of the view.
Label key features of the view on your photosketch or line drawing. The items that you label may depend on the focus of your research questions.
Include a heading, the date of the sketch and the website the view was sketched from.
Some schools may be able to do a field trip to Canada, however, for most schools if you use this case study, the best option would be to complete fieldwork on Environmental Change as a general topic in your local area, and complete virtual fieldwork on this case study. Below are some options to help you do this.
Observations
An important initial step in any fieldwork trip is observation. An observation helps provide the researcher with a broad view of the environment and can help frame initial research questions or provide general information about basic questions in your research.
Explore how the Google Maps team are helping build and share a Google Maps Tour of Churchill
Line drawing/Photosketch
Tools:
pen,
paper,
eraser,
ruler
Examine the scene and settle on a particular view
Draw a box (frame) for your sketch.
Draw a general outline of the view.
Label key features of the view on your photosketch or line drawing. The items that you label may depend on the focus of your research questions.
Include a heading, the date of the sketch and the website the view was sketched from.
