🌍 elss sg4

Question 1

location of arctic tundra

Answer 1

northern hemisphere
north of arctic circle at 66.5N

Question 1

size of arctic tundra

Answer 1

8 million km squared

Question 2

average annual temp of AT

Answer 2

-12.2 c

Question 3

annual temp change

Answer 3

33c

Question 4

average annual precipitation

Answer 4

137mm

Question 5

type of seasons

Answer 5

summer: 2-3 months, 2-3c, always light
winter: 8-9 months, -30c, dark for 3 months straight

Question 6

vegetation characteristics

Answer 6

no trees due to short growing season & low temps
some small shrubs in summer but very low NPP

Question 7

soil characteristics

Answer 7

active layer: ground that is frozen in winter but melts in summer
permafrost: permanently frozen ground for at least 2 years
talik: unfrozen ground

Question 8

precipitation in AT

Answer 8

very little and normally snow

Question 9

evapotranspiration in AT

Answer 9

low temps so little ET as not enough heat to melt ice/snow

Question 10

run off in AT

Answer 10

in summer more run off because ice melts, in winter stays frozen

Question 11

infiltration in AT

Answer 11

permafrost is impermeable so water can’t infiltrate

Question 12

store of water in atmosphere in AT

Answer 12

low temps so little ET

Question 13

store of water in soil and ground water in AT

Answer 13

permafrost is impermeable so no water can infiltrate into ground (very small store)

Question 14

store of water in vegetation in AT

Answer 14

not correct climate for vegetation to grow so very little water stored in it

Question 15

store of water on surface in AT

Answer 15

in summer, impermeable permafrost so puddles etc
in winter none because active layer freezes

Question 16

how does temperature in AT affect flows and stored in water cycle

Answer 16

very cold = low ET = so little stored in atmosphere
permafrost = impermeable surface = little stored in soil

Question 17

how does rock permeability and porosity in AT affect flows and stored in water cycle

Answer 17

active layer becomes waterlogged as ground is impermeable so active layer becomes water logged and surface storage and overland flow increases

Question 18

how does relief in AT affect flows and stored in water cycle

Answer 18

flat land due to weathering and erosion so lots of surface storage as doesn’t run off

Question 19

photosynthesis in arctic tundra

Answer 19

short growing season as bad climate for vegetation to grow so little photosynthesis

Question 20

respiration in arctic tundra

Answer 20

little respiration bc little vegetation and wildlife as too cold

Question 21

decomposition and soil respiration in arctic tundra

Answer 21

too cold for decomposition so very little
ground is frozen so soil organisms can’t respire

Question 22

carbon in the atmosphere in arctic tundra

Answer 22

small amount bc little respiration and decomposition

Question 23

carbon in biomass in arctic tundra

Answer 23

small amount due to low temps, little water availability, few nutrients so vegetation doesn’t grow

Question 24

carbon in permafrost in arctic tundra

Answer 24

large store bc when any vegetation does decompose, it stays frozen in soil for a long time

Question 25

variations of daylight and temperature in the arctic tundra

Answer 25

winter: 0-12 hours of sun so no photosynthesis or respiration (carbon source) summer: 12-24 hours of sun so permafrost melts and some carbon is released (carbon sink)

Question 26

vegetation and soil organic matter in the arctic tundra

Answer 26

sparse vegetation due to short growing season so very little photosynthesis not much soil respiration due to frozen ground

Question 27

how does the oil and gas industry impact the water cycle in arctic tunda

Answer 27

causes ice to melt - construction diffuses heat to ground which thaws permafrost - removal of trees = less shade = more melting - more concrete & dust lowers albedo

Question 28

what is the impact of ice melting in the arctic tundra in water cycle

Answer 28

increase in surface storage = more surface run off = increase in river discharge = flood risk increase increase in surface storage = more evaporation = more precipitation = flood risk increased

Question 29

is the impact local, national or global on water cycle

Answer 29

local as only increases local flood risk

Question 30

what is the trans alaskan pipeline (TAP)

Answer 30

800 mile pipeline through alaska to transport oil

Question 31

what % of alaskan jobs does oil industry account for

Answer 31

25%

Question 32

impact of oil and gas industry in alaska on carbon cycle

Answer 32

(positive feedback loop) permafrost melts releasing carbon dioxide → more atmospheric co2 less photosynthesis as vegetation removed for construction → more atmospheric co2 more decomposition due to melting permafrost so vegetation can decompose → more atmospheric co2

Question 33

is the impact on the carbon cycle local, national or global

Answer 33

global bc permafrost stores a lot of carbon so if it melts it would enhance global warming

Question 34

what is a themokarst landscape

Answer 34

irregular surfaces of marshy hollows with methane in them

Question 35

how do thermokarst landscapes spread

Answer 35

**positive feedback loop** permafrost thaws creating waterlogged depressions (big puddles) → water retains heat for longer than surrounding ground → more melting → depth of active layer increases → more permafrost thawing

Question 36

impact of darker surfaces and lower albedo

Answer 36

**positive feedback loop** more road and airstrips built → bright surfaces are now darker → lower albedo → more of suns energy absorbed by ground → more ice melting creating darker areas of muddy peat bogs → bright surfaces now dark

Question 37

impact on carbon cycle at global scale

Answer 37

**positive feedback loop** more co2 in atmosphere → temp increases due to greenhouse effect → permafrost thaws → organic matter can now decompose → more co2 and methane in atmosphere

Question 38

how does building infrastructure on gravel pads moderate carbon and water cycle

Answer 38

- insulates permafrost so less heat transfer to ground - less melting of permafrost - **eg airstrip at Deadhorse**

Question 39

how does building infrastructure on stilts moderate carbon and water cycle

Answer 39

- cold air can still circulate between permafrost and building - less melting of permafrost - **eg BP operation centre**

Question 40

how does building TAP on refrigerated stilts moderate carbon and water cycle

Answer 40

- insulated pipe to prevent heat loss from oil - cold air can still circulate so permafrost doesn’t melt - built on a track so can move which prevents leaks

Question 41

how could the melting of the permafrost cause a tipping point

Answer 41

higher temps = sea ice melts → darker ocean is exposed → lower albedo → more solar radiation absorbed → ice melts