Geography - Water and Carbon Cycles - The Global Hydrological Cycle

Question 1

global stores of water

Answer 1

• oceans
• lakes
• aquifers (underground lakes)
• the cryosphere (glaciers/ice sheets)

Question 2

local stores of water

Answer 2

• interception
• vegetation + surface storage
• soil moisture
• groundwater storage

Question 3

flows of water

Answer 3

• infiltration
• throughflow
• percolation
• stem flow
• base flow
• channel flow
• surface runoff

Question 4

processes of water

Answer 4

• precipitation
• evaporation
• transpiration
• cryosphere exchanges
• runoff

Question 5

total global water supply

Answer 5

• 96.5% of earths water is oceans and seas
• 2.5% of earths water is freshwater (Not salty)
• 1% of earths water is in other saline (salty) water sources

Question 6

freshwater

Answer 6

water that is not salty

• 68.8% of earths freshwater is in cryosphere
• 30% is groundwater
• 1.2% surface water

Question 7

surface water

Answer 7

69% ground ice + permafrost

-lakes, rivers, biosphere, swamps, marshes, atmosphere

Question 8

Water cycle

Answer 8

in a state of dynamic equilibrium if stores and transfers are balanced

Question 9

unbalanced dynamic equilibrium

Answer 9

• a change to one aspect of the water cycle will unbalance the dynamic equilibrium
• climate change is closely linked to changes in the water cycle

Question 10

negative feedback

Answer 10

decreases inputs in a system

i.e. water cycle is rising temperatures leading to more clouds which reflect sunlight and so reduced temperatures, stabilising the system

Question 11

positive feedback

Answer 11

increases inputs in a system

i. e. water cycle is rising temperatures leading to more water vapour in the atmosphere
- enhancing the greenhouse effect, increasing temperatures

Question 12

permafrost

-feedback mechanism

Answer 12

• as permafrost thaws CO2 and methane are released
• this contributes to greenhouse gases and enhances effect, increase in temp
• increase in temp leads to further melting of permafrost + more gases

Question 13

tipping points of systems examples

Answer 13

Forest Dieback
-if drought causes enough trees to die= tipping point

• no evapotranspiration as rainfall doesnt infiltrate due to dead vegetation
• overall rainfall also reduced, leads to further vegetation dying because reduced rainfall

The Thermohaline Circulation
-increased melting of northern glaciers results in large amounts of non salty less dense water entering oceans

• disturb hot water converyor belt moving to tropics
• the change in the system may result in cooling of temps in the nothern hemisphere