A-LEVEL GEOGRAPHY
EDEXCEL
WATER
PRACTICE QUESTIONS + ANSWERS
5.1
Explain how the global hydrological cycle acts as a closed system. (6)
● Closed means no energy is entering or exiting the system
● Water only moves around the earth, not in and out of it
Explain the processes that drive the hydrological system (6) HINT: You should be mentioning
solar energy and gravitational potential and explaining how they influence the flows.
● Solar energy drives evaporation and precipitation
● Gravity drives surface runoff and infiltration
The global hydrological system is driven by solar energy, and by gravitational pulls. The
solar energy affects the whole system through flows and residence time. Any water that
is exposed to the sun, such as surface storage, cryosphere and biosphere stores will be
exposed to the energy of the sun and evaporation. Through affecting the rate of
evaporation, it directly controls how much precipitation an area receives. It also drives
different pressure cells and atmospheric conditions that control global temperatures and
precipitation.
Gravitational potential affects the way surface stores move around the Earth, for
example rivers flowing around drainage basins are majorly affected by the relief of the
basin. Gravity will pull any water to the lowest point possible, and therefore all water on
the watershed of a basin will flow down to the lowest point in the basin. It also affects the
way water infiltrates through different rocks, and the path water takes to lead it to the
oceans and lakes via throughflow and surface runoff.
Explain the importance of oceans to the hydrological system. (6)
● Hold 97% of water
● Carbon sequestration
Explain the importance of the cryosphere to the global hydrological system (6)
,The cryosphere includes all frozen water on Earth, such as glaciers, snow, permafrost etc. The
cryosphere is important to the hydrological cycle because it is a very large store of water, and it
involves a significant flux between the oceans and glaciers. The cryosphere, in particular
glaciers and ice caps, account for 68% of global freshwater. This means it is heavily relied on
for drinking water by people who live downstream of glaciers, as the ice will melt annually and
supply large amounts of freshwater to the river’s discharge. For example, as glaciers and ice
melts more in the Yukon, the flows to the Yukon River have increased by 39% annually.
The cryosphere also plays a large role in the flow of water between the cryosphere and the
oceans. When glaciers and ice caps melt, they flow into the ocean either directly or through
rivers. The rate of the cryosphere melting will directly impact the size of the flow into oceans,
and therefore the size of the ocean as a store. As this rate increases due to anthropogenic
climate change, the size of the flow will increase and the ocean store will increase in capacity. If
all glaciers were to fully melt at any moment, the ocean levels would rise by 70 metres. River
regimes will also be largely affected, as they also receive snowmelt and as the amount of
snowmelt increases, rivers will see increases in discharge.
Explain why different water stores have different residence times (8)
● Amount of sunlight exposure
● Amount of water in that store
● Amount of movement
Explain how the global water budget can limit water for human use. (6) HINT: You should be
discussing the finite nature of water and stores such as fossil water and the cryosphere which
are non renewable.
● The amount of water that flows between stores
● Fossil and cryosphere water is not accessible, further limiting human access to water
● Limited amount of water in each store and in the world
Assess the relative importance of different water stores as a human water source (12)
● Cryosphere very important as many people get drinking water from there - 68% of
freshwater on earth. Mention rivers as a source of cryosphere water, Yukon River
increasing by 39%
● Underground water- 50% of people rely on groundwater for drinking source
● Importance of groundwater for a source of income, through irrigation and manufacturing
,Explain the factors that influence the speed of flows within the global hydrological system (6)
● Temperature will impact how long water stays in each store. With high evaporation,
flows will speed up
● Relief and geology will affect water flows between precipitation and ocean gain
● Abstraction from aquifers will speed up the flows as more water is exposed to surface
elements
● Glacial melting will act similarly, as water is brought into rivers and the ocean
5.2
Explain how humans disrupt the drainage basin cycle (8)
● Urbanisation interrupts surface runoff
● Flood management effects downstream people
● Vegetation and interception
● Amazonia where high levels of interception and evaporation create a cycle, cutting down
canopies reduces interception and evaporation and increases surface runoff and river
discharge
, Explain the different ways that precipitation can form (6)
Orographic- when moist air is lifted up over a mountain it cools and forms a cloud, then rains.
Frontal, when cold and warm air meet, the warm air rises and cools to form clouds, then rains.
Convectional- warm moist air rises from evaporation, cools to form clouds and rains, found in
tropical countries after warm days there will be storms.
Explain how precipitation can take different pathways to reach the ocean (6)
1. Surface runoff to rivers
2. Infiltration/percolation to through/ground flow
3. Freezing, joining the cryosphere, melting into the ocean
Explain how climate can influence inputs and flows in the drainage basin (6)
● Level of precipitation is dependent on climate
● Permeability of soils is impacted by the temperature, dry or soft soil
● Presence of vegetation and the impact of interception
Explain how geology and soils can influence flows in the drainage basin (6)
Explain how vegetation can influence inputs, flows and outputs in the drainage basin (6)
Explain how humans can disrupt the drainage basin by abstracting water (6)
● Lower water table, more water infiltrates so less water in rivers
● Drier soil and less plant life to intercept
Explain how humans, by changing land use, can disrupt the drainage basin cycle (8)
1. Urbanisation and impact on surface runoff, interception, flood risk
2. Farming increases interception; off-season presence of vegetation?
3. Damming rivers increases evaporation in certain areas, reduces river discharge
massively
Explain how river management by humans can disrupt the drainage basin cycle (6)
● Flood barriers increase river discharge, increases flows downstream
● Dams and reservoirs increase surface stores, and reduce downstream flows
● Having man-made flood plains reduces downstream flow and increases soil moisture
Assess the importance of the different physical factors that influence flows within the drainage
basin (12)
1. Precipitation- main factor as it is the only input to a drainage basin
2. Evaporation- large factor that impacts the volume of water that flows in the basin
3. Permeability- impacts the speed of flows, size of surface runoff
EDEXCEL
WATER
PRACTICE QUESTIONS + ANSWERS
5.1
Explain how the global hydrological cycle acts as a closed system. (6)
● Closed means no energy is entering or exiting the system
● Water only moves around the earth, not in and out of it
Explain the processes that drive the hydrological system (6) HINT: You should be mentioning
solar energy and gravitational potential and explaining how they influence the flows.
● Solar energy drives evaporation and precipitation
● Gravity drives surface runoff and infiltration
The global hydrological system is driven by solar energy, and by gravitational pulls. The
solar energy affects the whole system through flows and residence time. Any water that
is exposed to the sun, such as surface storage, cryosphere and biosphere stores will be
exposed to the energy of the sun and evaporation. Through affecting the rate of
evaporation, it directly controls how much precipitation an area receives. It also drives
different pressure cells and atmospheric conditions that control global temperatures and
precipitation.
Gravitational potential affects the way surface stores move around the Earth, for
example rivers flowing around drainage basins are majorly affected by the relief of the
basin. Gravity will pull any water to the lowest point possible, and therefore all water on
the watershed of a basin will flow down to the lowest point in the basin. It also affects the
way water infiltrates through different rocks, and the path water takes to lead it to the
oceans and lakes via throughflow and surface runoff.
Explain the importance of oceans to the hydrological system. (6)
● Hold 97% of water
● Carbon sequestration
Explain the importance of the cryosphere to the global hydrological system (6)
,The cryosphere includes all frozen water on Earth, such as glaciers, snow, permafrost etc. The
cryosphere is important to the hydrological cycle because it is a very large store of water, and it
involves a significant flux between the oceans and glaciers. The cryosphere, in particular
glaciers and ice caps, account for 68% of global freshwater. This means it is heavily relied on
for drinking water by people who live downstream of glaciers, as the ice will melt annually and
supply large amounts of freshwater to the river’s discharge. For example, as glaciers and ice
melts more in the Yukon, the flows to the Yukon River have increased by 39% annually.
The cryosphere also plays a large role in the flow of water between the cryosphere and the
oceans. When glaciers and ice caps melt, they flow into the ocean either directly or through
rivers. The rate of the cryosphere melting will directly impact the size of the flow into oceans,
and therefore the size of the ocean as a store. As this rate increases due to anthropogenic
climate change, the size of the flow will increase and the ocean store will increase in capacity. If
all glaciers were to fully melt at any moment, the ocean levels would rise by 70 metres. River
regimes will also be largely affected, as they also receive snowmelt and as the amount of
snowmelt increases, rivers will see increases in discharge.
Explain why different water stores have different residence times (8)
● Amount of sunlight exposure
● Amount of water in that store
● Amount of movement
Explain how the global water budget can limit water for human use. (6) HINT: You should be
discussing the finite nature of water and stores such as fossil water and the cryosphere which
are non renewable.
● The amount of water that flows between stores
● Fossil and cryosphere water is not accessible, further limiting human access to water
● Limited amount of water in each store and in the world
Assess the relative importance of different water stores as a human water source (12)
● Cryosphere very important as many people get drinking water from there - 68% of
freshwater on earth. Mention rivers as a source of cryosphere water, Yukon River
increasing by 39%
● Underground water- 50% of people rely on groundwater for drinking source
● Importance of groundwater for a source of income, through irrigation and manufacturing
,Explain the factors that influence the speed of flows within the global hydrological system (6)
● Temperature will impact how long water stays in each store. With high evaporation,
flows will speed up
● Relief and geology will affect water flows between precipitation and ocean gain
● Abstraction from aquifers will speed up the flows as more water is exposed to surface
elements
● Glacial melting will act similarly, as water is brought into rivers and the ocean
5.2
Explain how humans disrupt the drainage basin cycle (8)
● Urbanisation interrupts surface runoff
● Flood management effects downstream people
● Vegetation and interception
● Amazonia where high levels of interception and evaporation create a cycle, cutting down
canopies reduces interception and evaporation and increases surface runoff and river
discharge
, Explain the different ways that precipitation can form (6)
Orographic- when moist air is lifted up over a mountain it cools and forms a cloud, then rains.
Frontal, when cold and warm air meet, the warm air rises and cools to form clouds, then rains.
Convectional- warm moist air rises from evaporation, cools to form clouds and rains, found in
tropical countries after warm days there will be storms.
Explain how precipitation can take different pathways to reach the ocean (6)
1. Surface runoff to rivers
2. Infiltration/percolation to through/ground flow
3. Freezing, joining the cryosphere, melting into the ocean
Explain how climate can influence inputs and flows in the drainage basin (6)
● Level of precipitation is dependent on climate
● Permeability of soils is impacted by the temperature, dry or soft soil
● Presence of vegetation and the impact of interception
Explain how geology and soils can influence flows in the drainage basin (6)
Explain how vegetation can influence inputs, flows and outputs in the drainage basin (6)
Explain how humans can disrupt the drainage basin by abstracting water (6)
● Lower water table, more water infiltrates so less water in rivers
● Drier soil and less plant life to intercept
Explain how humans, by changing land use, can disrupt the drainage basin cycle (8)
1. Urbanisation and impact on surface runoff, interception, flood risk
2. Farming increases interception; off-season presence of vegetation?
3. Damming rivers increases evaporation in certain areas, reduces river discharge
massively
Explain how river management by humans can disrupt the drainage basin cycle (6)
● Flood barriers increase river discharge, increases flows downstream
● Dams and reservoirs increase surface stores, and reduce downstream flows
● Having man-made flood plains reduces downstream flow and increases soil moisture
Assess the importance of the different physical factors that influence flows within the drainage
basin (12)
1. Precipitation- main factor as it is the only input to a drainage basin
2. Evaporation- large factor that impacts the volume of water that flows in the basin
3. Permeability- impacts the speed of flows, size of surface runoff