L2: Arctic Drivers and Contrasts Flashcards
What does the Arctic being a large area mean for its climate?
There is a lot of variability in climate across the area (the regions being high arctic/ low arctic/ continental regions)
What are the key drivers that influence the climate of the Arctic?
Moisture and temperature
What is the characteristics of regional climate variability in Maritime Arctic?
It has a long freeze thaw season.
Being near the sea it means the climate is relatively mild and so has lots of freeze thaw cycles.
It also means there is lots of moisture and so lots of frost activity.
Lots of snow to insulate ground (warm relative to permafrost).
What is the characteristics of regional climate variability in Continental Arctic?
There are lots of short freeze thaw cycles and very few full ones.
Little moisture inputs but not losing lots to evaporation.
Little snow to insulate ground
Winter ground temperature extremely low.
What are the characteristics of temperature extremes in Maritime Arctic?
Small temperature extremes (winter frost penetration slight: summer slaw slow)
What are the characteristics of temperature extremes in Continental Arctic?
Large temperature extremes (winter frost penetration extreme: summer ground thaw rapid)
What landscape features does a Continental Arctic climate produce?
Deep freeze, large tundra polygons, widespread solifluction, maximum ground ice features.
What landscape features does a Maritime Arctic climate produce?
Rapid freeze thaw weathering and shattering, block fields, small patterned ground features.
What is the effect of altitude on temperature in Alpine climates?
Altitudinal decline in temperature
What does precipitation vary with in Alpine climates?
Precipitation varies with aspect (rain shadow- one side of mountain get more than the other)
Precipitation increases with altitude to a maximum, and then declines
What is precipitation strongly dependent on in Alpine climates?
Local winds and microtopography (e.g East and West Rockies).
Where is Glacier mass balance extremely rapid in Alpine climates?
Low latitudes
What are the outputs in Alpine climates?
Hydrology and landscape change
What is the hydrograph of Arctic environments like?
Very peaked hydrograph- large increase in flow in summer months (30-40% of flow occurs in one month)
What is the flow like Arctic environments?
Flow happens over a relatively short amount of time but that flow is extremely concentrated = power
Most rivers are ephemeral (don’t flow for most of the year, usually covered in ice for 6 months) then flood
The break up starts at the shore by the river banks, this is because it is likely to be free of snow and darker (warm up quicker), water will also be shallower and more likely for the incoming radiation to pass through ice and water and reflect, river is moving = thermal erosion
