ELSS - Case Studies - Arctic Tundra

Question 1

What is a Tundra?

Answer 1

A treeless region in the sub-Arctic which has a very short growing season and severe winter temperatures

Question 2

How big is the Arctic Tundra?

Answer 2

8 million km2

Question 3

Temperature

Answer 3

Very low average temperature
- -15’C
- for 8-9 months of the year the tundra has a negative heat balance

Question 4

Precipitation

Answer 4

Very low mean average of precipitation
- 100mm of precipitation but mostly snow

Question 5

Humidity

Answer 5

Very low humidity
- so cold that only a small amount of water can. be stored in the atmosphere
- low absolute humidity
- very dry

Question 6

Is there seasonal variation in the Tundra?

Answer 6

Tundra is at 60’ latitude therefore, there is huge seasonal variation
- winter months = axis pointed away from the sun = little insolation
- summer months = axis pointed towards the sun = huge insolation

Question 7

What is insolation?

Answer 7

Exposure to the sun’s rays

Question 8

Geology

Answer 8

Impermeable igneous and metamorphic rock

Question 9

Relief

Answer 9

Very flat land

Question 10

Growing season

Answer 10

Very short due to only 50-60 days of summer

Question 11

Physical factor affecting water cycle

Answer 11

• Insolation
• Geology
• Relief

Question 12

Water flows effected by physical factors (3)

Answer 12

• precipitation
• transpiration
• evaporation

Question 13

How is precipitation effected by physical factors?

Answer 13

• summer = low rates of precipitation
• winter = lower rates of precipitation

Question 14

How is transpiration effected by physical factors?

Answer 14

• summer = low rates of transpiration
• winter = no/little transpiration

Question 15

How is evaporation effected by physical factors?

Answer 15

• summer = low rates of evaporation as active layer melts creating pools and lakes
• winter = no evaporation

Question 16

Water stores effected by physical factors (3)

Answer 16

• vegetation
• humidity
• water storage (surface, ground, soil)

Question 17

How is vegetation effected by physical factors?

Answer 17

• summer = short, rapid growing season allowing grass and shrubs to grow and store water
• winter = no vegetation as covered in snow

Question 18

How is humidity effected by physical factors?

Answer 18

• summer = low humidity
• winter = lower humidity, very dry
  Very cold all year round so little water can be held in atmosphere so humidity is low all year round

Question 19

How is surface storage effected by physical factors?

Answer 19

• summer = active layer melts - creating pools and marshland as water cannot infiltrate impermeable rock
• winter = water on active layer freezes forming ice

Question 20

How is groundwater storage effected by physical factors?

Answer 20

Groundwater rocks (geology) are impermeable and thus, hold very little water

Question 21

How is soil storage effected by physical factors?

Answer 21

summer - active layer melts, saturating the soils but water is stored in permafrost all year round
winter - active layer freezes into ice

Question 22

Physical factors affecting the carbon cycle

Answer 22

• Insolation

Question 23

What is permafrost / soil’s role in the carbon cycle

Answer 23

• summer = active layer melts - carbon stored in frozen soil is released
• winter = active layer thaws - small amount of carbon released

Question 24

What is vegetation’s role in the carbon cycle

Answer 24

• summer = growing season - rapid growth of small flora - small store of carbon
• winter = no vegetation - no store of carbon

Question 25

What is photosynthesis's role in the carbon cycle

Answer 25

- summer = intense, long days of sunlight = high rates of photosynthesis - winter = no sunlight and no vegetation - little / no photosynthesis

Question 26

What is organic matter / decomposition's role in the carbon cycle

Answer 26

- summer = higher rates of decomposition, thawed active layer creates inundated land which reduces decomposition - winter = cold and dry - minimal decomposition

Question 27

Who manages the Arctic circle

Answer 27

Arctic council (made up of 8 countries)

Question 28

Why is an Arctic council needed

Answer 28

No one owns the Arctic but everyone wants it due to its profit opportunities in oil. Thus, the council is needed to stop conflict

Question 29

Why was the trans-Alaskan pipeline built?

Answer 29

To transport oil from Prudhoe bay (North Alaska) to the US

Question 30

How long is the trans-Alaskan pipeline?

Answer 30

1,300km 800 miles

Question 31

Impact of the trans-Alaskan pipeline on surrounding permafrost (4)

Answer 31

- manufacturing of pipeline caused the permafrost to become thinner and increasingly discontinuous - oil is carried at 60'C which melts surrounding permafrost - thawing permafrost can create risks for the pipeline - breakages in the pipe can cause mass environmental damage

Question 32

Impacts of oil and gas exploration on the water cycle (4)

Answer 32

- Melting of permafrost - Strip mining of sand and gravel - Artificial lakes at Goldstream - Disruption of drainage networks

Question 33

How has the melting of permafrost caused by exploration impacted the water cycle

Answer 33

- increase surface run off - increase river discharge = increased risk of flooding during summer ponds and lakes become more extensive, increasing evaporation and thus, precipitation

Question 34

How has the strip mining caused by exploration impacted the water cycle

Answer 34

- construction of lakes which disrupt drainage basin - exposes permafrost to increased melting

Question 35

How has the artificial lakes at Goldstream caused by exploration impacted the water cycle

Answer 35

- Lakes have been caused by 15m of permafrost melting in the past 60 years

Question 36

How has the disruption of drainage networks caused by exploration impacted the water cycle

Answer 36

- roads, construction and seismic explosions have disrupted drainage networks = increasing risk of flooding

Question 37

Impacts of oil and gas exploration on the carbon cycle (3)

Answer 37

- melting of permafrost - oil spillages - destruction of tundra vegetation

Question 38

How has the melting of permafrost impacted the carbon cycle

Answer 38

- releases CO2 and methane - 7-40million tonnes of CO2 released per year - 24,000-114,000 tonnes of methane release per year

Question 39

What melts the permafrost (3)

Answer 39

Permafrost is highly sensitive to changes in thermal balance - construction diffusing heat directly onto the environment - dust creates dark surfaces on the snow, increasing absorption of sunlight - removal of vegetation which protects the permafrost

Question 40

How has the oil spillages impacted the carbon cycle

Answer 40

Input CO2 into the atmosphere

Question 41

How does the destruction tundra vegetation impact the carbon cycle

Answer 41

Reduces photosynthesis - reduced uptake of CO2 in the atmosphere to biosphere

Question 42

Why should the Artic permafrost be protected?

Answer 42

The Tundra stores 1600GigaTonnes of carbon which would be extremely detrimental to the climate if it were released - sea level rise - destruction of habitats Protecting it would prevent the thawing of permafrost - reducing global warming - positive feedback loop

Question 43

Buildings / pipeline elevated on stilts

Answer 43

- Global scale - Constructing buildings, oil/gas pipelines on stilts allows cold air to circulate beneath these structures - Prevents local permafrost from thawing - V. expensive

Question 44

Drilling laterally from drilling rigs

Answer 44

- Local scale - New drilling techniques allow oil and gas to be accessed several kilometres away from the drilling site. Shell has developed the 'snake' drill, which allows for directional drilling across a wide area from a single drilling site - With fewer sites needed for drilling rigs, the impact on vegetation and the permafrost is greatly reduced - V. expensive and damages local permafrost

Question 45

Refrigerated supports on the legs of the Trans-Alaska pipeline in the Arctic

Answer 45

- Local scale - Refrigerated supports are used on the trans-Alaska pipeline to stabilise the temperature of the permafrost. - Similar supports are widely used to conserve the permafrost beneath buildings and other infrastructure. - V. expensive

Question 46

Insulated ice and gravel pads in the Arctic

Answer 46

- Local scale - Roads and other infrastructural surfaces can be constructed on insulating ice or gravel pads -Protects the permafrost. E.g the spine road at Prudhoe bay lies on a 2m deep pap - V. expensive

Question 47

More powerful computers for detection in the Arctic?

Answer 47

- Local scale - Fewer exploration wells are needed thus reducing the impact on the environment - V. expensive

Question 48

Polar code 2017

Answer 48

- Global scale - Places limitations on the discharge of oil, sewage, and rubbish on ships passing through the Arctic - Protects the environment - Difficult to enforce