Arctic Tundra - Water

• What are some of the characteristics of the Arctic Tundra's water cycle?

  • Low annual precipitation (less than 100mm) mostly snow
  • Small stores in the atmosphere due to low temperatures and humidity
  • Limited transpiration due to low vegetation cover - short growing season of 3 months
  • Low evaporation rates + limited ground and surface water stores as permafrost is a barrier to infiltration and percolation
  • Melting of the active layer in the spring causes increase in river flow
  • Temporary stores of water in wetlands, ponds and lakes in summer due to PF limiting drainage
• What are some of the flows and stores in the water cycle in the Tundra?

  • Temperature
  • Relief
  • Rock permeability
• How does temperature affect the water cycle in the Tundra?

  • Averages are below freezing so water is stored in permafrost
  • Active layer thaws in summer + increased flows on surface
  • Pools/lakes are formed as there is poor drainage due to barrier to infiltration
  • Lack of evapotranspiration due to low humidity and precipitation
• How does relief affect the water cycle in the Tundra?

  • Erosion and weathering has resulted in a gently rising/falling plain.
  • This plus glacial deposits reduce drainage and contribute to waterlogging in the summer
• How does rock permeability affect the water cycle in the Tundra?

  • Low permeability due to permafrost and rock types e.g., metamorphic
• What are some of the Tundra's water cycle components?

  • Vegetation
  • Atmosphere
  • Soil/ground
  • Run-off
  • Evapotranspiration
  • Precipitation
• How does vegetation affect the Tundra's water cycle?

  Low flows due to limited vegetation and short growing season
• How does atmosphere affect the Tundra's water cycle?

  Small stores of water due to low temperatures
• How does the soil/ground affect the Tundra's water cycle?

  Limited stores underground as permafrost acts as a barrier to infiltration, percolation

  Summer melting causes temporary stores of water above ground as water cannot drain due to permafrost
• How does run-off affect the Tundra's water cycle?

  Usually little flow but melting of active layer in summer can cause rapid increase in run-off and river flow
• How does evapotranspiration affect the Tundra's water cycle?

  Low temperatures = low rates of evapotranspiration - sun's energy spent melting snow - most water remains frozen
• How does precipitation affect the Tundra's water cycle?

  Low annual precipitation (less than 100mm)
• What are the 3 physical factors affecting the water cycle?

  • Geology
  • Temperature
  • Relief
• How does Geology affect the Tundra's water cycle?

  • Hard rocks add to the low permeability already present due to permafrost
• How does temperature affect the Tundra's water cycle?

  • Low temperatures keep water stored as permafrost
  • Short summer melt causes some water to flow on the surface (active layer)
  • Little evapotranspiration, although some in summer from surface water
• How does relief affect the Tundra's water cycle?

  • gentle sloping relief helps to store water during the summer months, waterlogging soils