Periglacial Landscape Impacts Case Study - Alaska Flashcards
How much oil is known to be in Alaska’s oil reserves?
25 billion barrels.
Where does the Alyeska pipeline in Alaska run to and from, and how much oil is transported along the pipeline a day?
From Prudhoe Bay on the north coast to Valdez on the south coast, and transports 500,000 barrels of oil a day.
In what two ways are hydrological processes affected by gravel extraction in Alaska?
- Groundwater levels fall, such as an area over 2km from the gravel extraction site where the water table fell by over 1m.
- The equilibrium of local rivers, and gravel transport and deposition rates are affected by gravel extraction.
Why is gravel extracted in Alaska?
To create gravel pads, which are used to insulate the bases of roads.
What is flaring and how does it negatively affect the periglacial landscape of Alaska?
Flaring is the burning of gases whilst drilling, which releases greenhouse gases (mostly CO2) into the atmosphere, contributing to an enhanced greenhouse effect.
In what two ways does drilling in Alaska cause an urban heat island effect?
- Drilling processes emit thermal energy.
- Improperly insulated buildings release heat into the surroundings.
How large was the urban heat island effect present in the small town of Barrow, Alaska?
Rural average temperatures were on average 2.2 degrees Celsius lower than temperature recordings in the town.
How many less days of 0 degrees Celsius temperature fluctuation were there since drilling began?
9% less.
How is ground ice thawing sped up by human activity?
Removal of vegetation for construction or other uses.
What are subsidence rates in the north of Alaska?
3-4cm a year with a maximum of 12cm a year.
How deep is the permafrost and active layer in the north of Alaska?
The permafrost is 300-600m deep, and the active layer is 30-80cm deep.
