Cold Environments

• Polar Climate?

  • normally below freezing
  • winters tend to drop to -40 degrees and can reach -90 degrees
  • precipitation is less than 100 mm a year
• Tundra Climate?

  • warm months only reach 10 degrees
  • winters can plunge to -50 degrees
  • precipitation is less than 380 mm in a year
• Soil?

  Beneath thin soil is a layer of permafrost (frozen ground), holding trapped greenhouse gases.
• Polar soil?

  Ice sheets cover polar areas, so no soil is exposed. Soil is permanently frozen (permafrost).
• Tundra soil?

  • thin
  • acidic
  • generally infertile
  • soils are frozen, but melt on the surface in summer
  • high in dead organic matter (too cold for decomposition)
• What animals are found in polar areas?

  • polar bears
  • penguins
  • whales
  • seals
• What animals are found in tundra areas?

  • lemmings
  • wolves
  • reindeer
• What plants are found in polar areas?

  • lichens and mosses grow on rocks
  • grasses grow on the coast
• What plants are found in tundra areas?

  • hardy shrubs (e.g. bearberry)
  • grasses
  • mosses
  • lichens
  • treeless
• Who lives in polar areas?

  Polar areas are mostly uninhabited, but the Arctic has some Indigenous residents and a few scientists work in Antarctica.
• Who lives in tundra areas?

  Tundra areas are home to many indigenous people, as well as oil and gas workers in larger towns.
• Polar areas:

  Inland areas, away from the warming influence of the sea.

  Examples:

  • Greenland
  • Northern Canada
  • Northern Russia (Siberia)
  • Antarctica
• Tundra areas:

  • Northern Hemisphere
  • South of the ice caps
  • 1/5 of the earth's land surface

  Examples:

  • Russia
  • Canada
  • Alaska
• Animal Adaptations - Polar Bears:

  • retain heat with thick fur and an insulating layer of fat
  • black nose & black foot pads to absorb heat from the sun
  • hibernate during winter (because of lack of food and low temperatures) using the thick layer of fat built up
  • large feet - to distribute their load and increase grip on ice
  • white fur - as camouflage from prey on snow and ice
• Tundra is a fragile environment and can take a very long time to recover from any damage that is done by human activity.
• Adaptations of plants in cold environments:

  Rapid flowering and seed formation, low-growing and cushion-like, hairy stems, small and waxy leaves.
• Cold environments have very low biodiversity (particularly Antarctica) - there are fewer species of plants and animals in cold environments than in most other environments.
• Low biodiversity means when the population of one species changes, it can affect the population of dependent species (e.g. changes to the lemming population will affect the populations of their predators)
• Global warming is causing some species to move towards the poles, where it is colder, in response to temperature rises in their natural habitat. Species already adapted to polar environments can't go anywhere colder, so are at risk of decline or extinction if climate change causes the polar areas to warm up too much.
• Plant adaptations to cold environments:

  • low-growing and round-shaped to provide protection from wind
  • shallow roots because of the permafrost layer beneath the soil
  • leaves are small to limit the amount of moisture lost through transpiration
• Adaptations of the bearberry plant

  • less than 15 cm off the ground with a stick stem to protect from winds
  • hairy stem to keep warm
  • small bright green leathery leaves to maximize photosynthesis and retain moisture
  • bright red berries which attract birds that help with seed dispersal
• Technological solutions for the trans-Alaskan pipeline

  • Pumping stations keep the oil moving
  • The pipeline passes beneath rivers to minimize the impact on the landscape
  • The pipeline is raised and insulated to retain heat and prevent damaging the permafrost
  • The pipeline is supported and can slide if earthquakes happen, and the flow of oil stops automatically if there is a leak
  • The pipeline is raised to allow caribou to migrate underneath
• In 1974 the trans-Alaskan pipeline was opened, enabling oil to be transported 1300 km from Prudhoe Bay to the port of Valdez.
• Trans-Alaskan pipeline



  • Crosses rivers and mountains
  • Oil from the ground is very hot (40°C) which helps it to flow, but could melt the permafrost
  • Possible cracks caused by earthquakes can cause oil leaks
  • Large herds of animals such as caribou migrate across the route of the pipeline
• Cold environments offer many opportunities for economic development.
• Development Opportunities in Alaska

  • Energy - oil and gas industry
  • Mineral Resources - materials such as gold, silver, iron ore, copper
  • Fishing
  • Tourism
• Challenges to Development in Alaska

  • Alaska's state population is one of the smallest in the US, despite being the largest state by area. Most people live on the state's southern and south-eastern coastline where it is warmer and less remote
  • It's difficult to access resources and find a workforce in Alaska because of the extreme conditions, remote location and poor infrastructure.
• Extreme Temperatures - Alaska

  • annual temperature is around -9 degrees with snow and strong winds
  • Exposure to them can kill and healthcare is usually at a distance
  • Vehicle and equipment failures are common and getting them repaired is difficult and time-consuming
  • Extremes in the amount of daylight – in winter it can be dark nearly all the time and mental health issues are common
• Accessibility - Alaska

  • Over 21 hours by road from the US
  • Many areas are extremely remote
  • Mountainous terrain makes access difficult and expensive
  • In winter, access to some towns is either by air or on dangerous ice roads
  • In summer, some main roads are impassable due to ground melt
• With a small and scattered population, people in small towns can be a long way from employment opportunities or services and goods
• Everyday goods (food, drink, clothing, toys etc.) are very expensive as they have to be shipped in and during the winter months it can take weeks or months for shipments to arrive to Alaska.
• Buildings and Infrastructure - Alaska

  • Buildings and infrastructure need to cope with the frozen ground and weather conditions, this makes it difficult and expensive to build in Alaska
  • Most building work has to take place during the summer as the days are longer and temperatures warmer
• The value of Alaskan resources, means finding ways to adapt to the challenges:

  • In areas of permafrost, houses are raised on stilts to prevent their heat from melting the frozen ground beneath (which can cause the land to sink and subside)
  • Reducing heating costs through triple-glazed homes and geothermal power
  • Alaskan roads are built on 1-2-metre-thick gravel pads that stop heat transferring from vehicles to the soil beneath which would cause permafrost to melt and roads to crack
• Cold environments are extremely fragile - it can take centuries for them to return to their original state after human interference. This is because:

  • Plant growth is slow - if plants are damaged (e.g. by vehicle tyres) regrowth takes time
  • Species are highly specialised so find it difficult to adapt to change. E.g. polar bears are adapted to hunt on ice - their numbers are decreasing as sea ice melts earlier each year.
• It is important to conserve wilderness areas in cold environments because:

  • They provide habitats for organisms that couldn't survive elsewhere
  • Scientists can study natural environments including landforms, plants and animals that are relatively unaffected by people - this provides valuable knowledge about fragile ecosystems
  • Studying natural ecosystems may help scientists replicate the same conditions in managed ecosystems. This can help preserve rare species outside the protected areas
• Strategies used to balance economic development and conservation in cold environments

  • International Agreements
  • Conservation Groups
  • Using Technology
  • The role of Governments
• Strategies - Using Technology

  • development can cause problems (e.g. heated buildings can melt permafrost, leading to subsidence which may cause buildings to collapse and pipes to crack)
  • However, modern construction methods can minimise environmental impacts (e.g. by building on gravel beds to prevent buildings from warming the ground)
• Strategies - Conservation Groups

  • Conservation groups (e.g. Greenpeace and the WWF) pressure governments to protect cold environments
  • This can lead to more sustainable development that doesn't damage at-risk areas
• Strategies - The role of the Governments

  • Unregulated development can damage the environment (e.g. mining can pollute water and oil pipelines can disrupt animal migration)
  • Governments can pass laws such as the 1964 Wilderness Act, to protect designated wilderness areas (e.g. much of Alaska) from development. This means that development has to take place elsewhere, reducing conflict over land use in wilderness areas
• Strategies - International Agreements

  • Some cold environments are protected by international agreements (e.g. Antarctica)
  • The 1959 Antarctic Treaty, signed by 12 nations, limits visitors to 100 per site, ensures peaceful non-military activities, prohibits nuclear activities, and prevents cruise ships with over 500 passengers from stopping
  • This allows tourism, but in a controlled way that won't harm the fragile ecosystem