1.3 The water cycle and water insecurity Flashcards

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1
Q

What % of the world’s water do oceans store?

A

97%

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2
Q

What % of the world’s water is freshwater?

A

2.5%

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3
Q

Of the freshwater, what % is stored in glaciers, ice caps, and ice sheets?

A

69%

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4
Q

Of the freshwater, what % is stored as ground water?

A

30%

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5
Q

Of the freshwater, what % is surface and other freshwater sources?

A

1%

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6
Q

What are other surface and freshwater stores made up of?

A

permafrost, lakes, swamps, marshes, rivers and living organisms.

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7
Q

Define blue water

A

water stored in lakes, rivers, streams, and ground water, in liquid form

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8
Q

Define green water

A

water stored in soil and vegetation

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9
Q

Define grey water

A

waste bath, sink, and washing water

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10
Q

Describe the hydrology in polar regions (6)

A

▪ 85% of solar radiation is reflected
▪ Permafrost creates impermeable surfaces
▪ Lakes and rivers freeze
▪ Rapid runoff in spring
▪ Seasonal release of biogenic gases into atmosphere
▪ Orographic and frontal precipitation

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11
Q

Describe the hydrology in tropical rainforests (6)

A

▪ Dense vegetation consuming 75% of precipitation
▪ There is limited infiltration
▪ Deforestation leads to less evapotranspiration and precipitation
▪ Very high temperatures
▪ Very humid
▪ Convectional rainfall

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12
Q

Describe the Inter-Tropical Continental Zone (ITCZ)

A
  • The Earth consist of six cells of circulating air, which form the globe’s climate control
  • There are 3 in the northern hemisphere, and 3 in the opposite direction in the southern hemisphere
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13
Q

Define drainage basin

A
  • A drainage basin is an open subsystem operating within the closed global hydrological cycle.
  • an area of land drained by a river and its tributaries with a boundary (known as the watershed), usually composing of hills and mountains. `
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14
Q

Define drainage basin

A
  • A drainage basin is an open subsystem operating within the closed global hydrological cycle.
  • It’s defined as an area of land drained by a river and its tributaries with a boundary (known as the watershed), usually composing of hills and mountains.
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15
Q

is the water cycle an open or closed system?

A
  • On a local scale, the water cycle is an open system
  • on a global scale, the water cycle a closed systems
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16
Q

What is the main input into a drainage basin?

A

precipitation

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17
Q

Cause of precipitation

A

Precipitation is caused by the cooling and condensation of water moisture in the atmosphere, forming clouds that release moisture in the form of rain, snow, hail, sleet, etc.

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18
Q

Factors affecting volume or condition of precipitation (3)

A
  • seasonality
  • climate variability
  • latititude
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19
Q

How does seasonality affect precipitation?

A
  • In some climates (such as monsoon and Mediterranean) there are strong seasonal patterns of rainfall.
  • Therefore the time of year determines the precipitation input within the drainage basin
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20
Q

How does climate variability affect precipitation?

A
  • sudden or long term changes to the climate can happen, which would affect precipitation levels and so the drainage basin as a whole.
    → Secular Variability – long term (for example as a result of climate change trends)
    → Periodic Variability – annual, seasonal or monthly context
    → Stochastic Variability – random factors like localisation of thunderstorm
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21
Q

How does latitude affect precipitation?

A
  • The location of the drainage basin has a major impact on climate, and so the volume and type of precipitation falling.
  • In most cases, the higher the latitude from the Equator, the colder the climate, and so snowfall occurs more often than rainfall.
  • Also, at latitudes where air cells converge (ITCZ), the climate will be categorised by the rise or fall of air
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22
Q

Name the three types of rainfall

A
  • convectional
  • frontal/cyclonic
  • relief/orographic
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23
Q

Describe convectional rainfall

A
  • Often a daily occurance.
  • The morning heat warms the ground, which in turn heats low-level moisture (from plant dew or surface stores).
  • This moisture evaporates and rises.
  • As the air rises, it cools and the moisture within will condense, to form rain and in turn (as more moisture accumulates) rainfall.
  • In tropical climates, convectional rainfall is most common; within tropical rainforests, rainfall occurs mid-morning before the temperature rises too high for condensation to occur.
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24
Q

Describe frontal/cyclonic rainfall

A
  • Where two air masses meet, a wedge can occur of hot air within cold air - this is called a depression.
  • At the front (were the two air masses meet), warm moist air is forced to rise above the cold air mass, causing the water moisture within to cool and condense, to form cyclonic precipitation.
  • Depressions are very common to the UK - approx 100 depressions hit the UK each year.
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25
Q

Describe relief/orographic rainfall

A
  • When warm, moist air (often travelling onto land from sea) meets land of high relief (e.g. hills), the air mass is forced to rise above the hill to continue travelling.
  • As it rises, the air mass cools and the moisture within condenses, to form clouds and rainfall.
  • Orographic rainfall depends on the relief and location of the land immediate after the sea - many coastal landscapes are too cold, low lying or hills are set too far inland for relief rainfall to occur
  • causes rain shadow on other side of high land
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26
Q

Define discharge

A

the volume of water passing a certain point in the channel over a certain amount of time

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27
Q

Name the flows within a drainage basin (6)

A
  • interception
  • infiltration
  • surface runoff
  • throughflow
  • percolation
  • groundwater
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28
Q

How does relief affect basin flows?

A

There are many flows within the drainage basin, many due to gravity and so depend on the relief of the land

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29
Q

Describe interception

A
  • Interception is the direct intervention of plants’ leaves in changing the direction or temporarily stopping precipitation as it falls to the surface.
  • Any moisture retained by the surface of the leaf (interception store) is generally greatest at the start of storms.
  • A plant’s interception capacity varies depending on the type of vegetation.
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30
Q

Describe infliltration

A

The movement of water from the surface into the soil

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31
Q

Define infiltration capacity

A

The infiltration capacity is the maximum rate at which water can be absorbed by the soil

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32
Q

Factors affecting infiltration capacity (5)

A

▪ Soil Composition – Sandy soils have higher infiltration rates compared to clay.
▪ Previous precipitation - The saturation of soils will reduce infiltration rates, hence surface runoff increases after long, intense periods of rainfall.
▪ Type and amount of vegetation - dense root growth can inhibit the infiltration of water, and interception of plants’ leaves will delay infiltration
▪ Compaction of soils will reduce the infiltration rate.
▪ Relief of land – sloped land will encourage more runoff, therefore less infiltration as a direct result

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33
Q

Describe surface runoff

A
  • Water flows overland, rather than permeating deeper levels of the ground.
  • Overland flow occurs faster where the gradient of land is greater.
  • Surface runoff if the primary transfer of water to river channels, hence heavily influencing their discharge
  • Moderate/Fast rate of water transfer
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34
Q

Describe throughflow

A
  • Water moves laterally through the soil and into streams or rivers.
  • Speed of flow is dependent on the type of soil
  • Clay soils with a high field capacity and smaller pore spaces have a slower flow rate
  • Sandy soils drain quickly because they have a lower field capacity, larger pore spaces and natural channels from animals such as worms.
  • Moderate/Fast rate of water transfer
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35
Q

Describe percolation

A
  • Water moves from the ground or soil into porous rock or rock fractures (deeper bedrock and aquifers).
  • The percolation rate is dependent on the fractures that may be present in the rock and the permeability of the rock
  • Slow rate of water transfer
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36
Q

Describe groundwater flow

A
  • The gradual transfer of water through porous rock, under the influence of gravity.
  • Water can sometimes become trapped within these deeper layers of bedrock, creating aquifers and long water stores for the drainage basin
  • Slow rate of water transfer
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37
Q

Outputs of the drainage basin (2)

A
  • evaporation
  • transpiration
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38
Q

Describe evaporation

A

This is the direct loss of water moisture from the surface of a body of water, the soil and interception storage (on top of leaves) to the atmosphere

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39
Q

Factors increasing evaporation rate (4)

A
  • Evaporation rates increase when the weather is warmer, windier and dryer.
  • Volume and surface area of the water body - the larger the surface area, the faster the rate of evaporation.
  • Vegetation cover or built environment surrounding the water - anything that reduces direct sunlight to the water body will reduce evaporation.
  • The colour of the surface beneath the water - black tarmac will absorb heat faster than white snow, and so evaporation will occur faster on the tarmac
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40
Q

Describe transpiration

A

This is a biological process where water is lost to the atmosphere through the pores of plants (stomata)

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41
Q

Factors affecting transpiration rates (4)

A
  • seasonality
  • type of vegetation
  • moisture content of the air
  • time of day
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42
Q

Stores of water (5)

A
  • soil water (mid-term)
  • groundwater (long-term)
  • river channel (short-term)
  • interception (short-term)
  • surface water (variable)
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43
Q

Define cryosphere

A

areas of the earth where water is frozen into snow or ice

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44
Q

Define fluxes

A

the rate of flow between the stores

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45
Q

Define residence time

A

the average time a water molecule will spend in a store

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46
Q

Define water table

A

The water table is the upper level at which the pore spaces and fractures in the ground become saturated.

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47
Q

Physical factors affecting the drainage basin (6)

A
  • climate
  • soil composition
  • geology
  • relief
  • vegetation
  • size
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48
Q

How does climate affect a drainage basin?

A

influences amount of rainfall and vegetation growth.

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49
Q

How does soil composition affect a drainage basin?

A

influences rate of infiltration and throughflow.

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50
Q

How does geology affect a drainage basin?

A
  • affects percolation and groundwater flow
  • permeability of rock, angle of strata
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51
Q

How does relief affect a drainage basin?

A

steeper gradients of land will encourage faster rates of surface runoff

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52
Q

How does vegetation affect a drainage basin?

A
  • affects interception, overland flow
  • as vegetation becomes wetter, interception effectiveness decreases
  • vegetation type and cover affect interception rate
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53
Q

How does size affect a drainage basin?

A

larger basins collect more precipitation generally

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54
Q

Human factors affecting drainage basins (8)

A
  • cloud seeding
  • deforestation
  • afforestation
  • dam construction
  • change in land use
  • ground water abstraction
  • irrigation
  • urbanisation
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55
Q

Describe cloud seeding

A
  • silver iodide released by a plane or ground based generator
  • silver iodide particles reach the targeted cloud
  • silver iodide aids in the formation of ice crystals
  • ice crystals become large enough to fall and create snow
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56
Q

How does deforestation affect a drainage basin?

A

Less vegetation means less interception, less infiltration, more overland flow, leading to more flooding, cycle speeds up

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57
Q

How does afforestation affect a drainage basin?

A

More vegetation means interception, less overland flow, more evapotranspiration

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58
Q

How does dam construction affect a drainage basin?

A

Dams reduce downstream river flow and discharge, increase surface stores so more evaporation

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59
Q

How do changes in land use affect a drainage basin?

A
  • Infiltration is 5 times faster under forests compared to grasslands.
  • Converting land to farmland means less interception, increased soil compaction and more surface runoff
60
Q

How does ground water abstraction affect a drainage basin?

A

When water is taken out faster that the water is recharged, groundwater flow decreases and the water table drops

61
Q

How does irrigation affect a drainage basin?

A

Drop in water tables due to high water
usage.

62
Q

How does urbanisation affect a drainage basin?

A
  • Impermeable surfaces reduce infiltration, increase surface runoff, river discharge increase.
  • Cycle speeds up
63
Q

What do water budgets show?

A

the annual difference between inputs and outputs

64
Q

Precipitation equation

A

Precipitation = discharge + evaporation +/- changes in stores

65
Q

Define positive water balance

A

precipitation exceeds evapotranspiration, perhaps causing flooding

66
Q

Define negative water balance

A

evapotranspiration exceeds precipitation, potentially leads to droughts

67
Q

Define soil moisture recharge

A

As precipitation exceeds evaporation rates, the soil will regain moisture and reduce its deficit

68
Q

Define soil moisture surplus

A

when soil has become saturated so excess water has difficulty soaking into the ground

69
Q

Define soil moisture deficit

A

when all the water in soil has been used up by evapotranspiration

70
Q

Define soil moisture utilisation

A

As temperature increases, the rate of evaporation will increase. The soil uses the moisture gained during its surplus so there is a reduction in the amount of water stored in the soil. Some is transferred at throughflow

71
Q

Define river regime

A

the annual variation in discharge of a river at a particular location

72
Q

Describe seasonal variations in river regime

A
  • periods of high discharge followed by low discharge
  • due to glacial meltwater, snowmelt or monsoons which cause sudden fluctuations in river input
73
Q

Factors affecting the characteristics of a river’s regime (6)

A
  • Channel capacity of the river
  • Area and relief of the drainage basin
  • Volume, pattern and intensity of precipitation
  • Climate
  • Geology of the soil (affecting the input of groundwater)
  • Human activities, such as building dams or terracing the land.
74
Q

what do storm hydrographs show?

A
  • Storm hydrographs represent the variation in discharge within a short period of time (days, rather than years)
  • Before a storm begins, the main supply of water to the river is through groundwater or base flow.
  • However, as a storm develops, infiltration and surface runoff will increase which causes a greater throughflow.
75
Q

Features of a storm hydrograph (5)

A

▪ Rising limb (increase of river discharge)
▪ Peak flow (maximum discharge, delayed after maximum precipitation has occurred)
▪ Lag time (time delay between peak rainfall and peak discharge)
▪ Falling limb (As the storm precipitation levels decrease, discharge will in turn decrease)
▪ Base flow (discharge returns to its normal level)

76
Q

Factors influencing hydrographs (8)

A
  • weather/climate
  • rock type
  • soil
  • relief
  • basin size
  • vegetation
  • pre-existing conditions (e.g. basin being wet from previous rainfall)
  • human activity (urbanisation, deforestation, dams)
77
Q

Management schemes that try to reduce surface run off (4)

A

▪ Growing vegetation on roofs, to increase interception and temporarily stores some water within plants.
▪ Create permeable pavements (gaps within paving blocks) to increase infiltration and reduce surface runoff .
▪ Rainwater Harvesting – collecting rainwater to use as domestic greywater
▪ Creating wetlands that will act as natural sponges and increase temporary water storage.

78
Q

Impacts of human development on a basin (4)

A

▪ Deforestation - Soil becomes exposed and roots are lost, which leads to more soil erosion and so more surface runoff.
▪ Impermeable surfaces – As more tarmac and concrete is laid, less infiltration into the topsoil can occur, and so more surface runoff occurs.
▪ Bridges can act as dams for rivers, restricting channel flow and increasing the pressure the river’s water is under, worsening flood impacts.
▪ Drainage and sewage systems will reduce lag time, and so a quick flow of water back to rivers, increasing the risk of flash flooding.

79
Q

Define drought

A

a deficit in the hydrological cycle

80
Q

Types of drought (4)

A
  • Meteorological (rainfall deficit)
  • hydrological (stream flow deficit)
  • agricultural (soil moisture deficit)
  • socio-economic (food deficit)
81
Q

meteorological drought - features (5)

A
  • Low precipitation
  • High temperatures
  • Strong winds
  • Increased solar radiation
  • Reduced snow cover
82
Q

Meteorological drought - impacts (3)

A
  • Loss of soil moisture
  • Irrigation supply drops
  • Reduction in water available for consumption.
83
Q

Hydrological drought - features (3)

A
  • Reduced infiltration
  • Low soil moisture
  • Little percolation and groundwater recharge
84
Q

Hydrological drought - impacts (4)

A
  • Reduced storage in lakes and reservoirs
  • Less water for urban supply
  • Poorer water quality
  • Threats to wetlands and habitats
85
Q

Agricultural drought - features (3)

A
  • Low evapotranspiration
  • Reduced biomass
  • Fall in groundwater level
86
Q

Agricultural drought - impacts (5)

A
  • Poor yields from rainfed crops
  • Failing irrigation systems
  • Livestock productivity falls
  • Rural industries affected
  • Government aid may be required
87
Q

Socio-economic drought - features (4)

A
  • Loss of vegetation
  • Increased risk of wildfires
  • Soil erosion
  • Desertification
88
Q

Socio-economic drought - impacts (6)

A
  • Widespread failure of agricultural systems
  • Food shortages
  • Rural economy collapses
  • Rural to urban migration
  • International aid required
  • Humanitarian crisis
89
Q

What does ENSO stand for?

A

El Nino Southern Oscillation

90
Q

Describe normal conditions under ENSO

A
  • wind travels westwards over pacific, taking warm surface waters with it
  • Cold Peruvian current that flows northwards along west coast of South America is drawn into circulation and flows westwards
  • as it flows west it is heated by the sun
  • warm moist air rises over Indonesia, creating low-pressure and heavy rain
  • air the circulates and sinks over Western South America, creating high pressure and dry conditions
91
Q

Define El Nino

A
  • El Nino is the change in water body patterns within the Southern hemisphere, leading to unusual weather conditions
  • usually occurs every 3 to 7 years, generally lasting for 18 months.
92
Q

impacts of El Nino

A
  • pressure systems and weather patterns reverse
  • warmer waters develop in the eastern Pacific
  • low pressure forms, drawing in westerly winds from the pacific
  • Warm moist air rises, creating heavy rainfall over the east pacific
  • the air then circulates west
  • ENSO can also trigger extremely dry conditions in areas South & South-East Asia, Eastern Australia and North-East Brazil.
  • In South Asia ENSO can weaken the annual monsoon
93
Q

Describe la nina

A
  • normal conditions intensify
  • low pressure over the western pacific becomes lower, and high pressure over the eastern pacific higher
  • rainfall increases over Southeast Asia, and South America suffers drought
  • Trade winds strengthen due to increased pressure difference between the two areas
  • La nina can occur just before or after el nino
94
Q

Functions of wetlands (3)

A
  • Wetlands act as temporary water stores within the hydrological cycle, which can help mitigate from river floods due to sudden storm discharge.
  • Chemically, wetlands act like water filters by trapping and recycling nutrients and pollutants, which helps to maintain water quality of the river.
  • Wetlands have very high biological productivity and support a very diverse food web, providing nursery areas for fish and refuges for migrating birds
95
Q

How are wetlands valuable for supporting life?

A
  • Stores and flows of carbon (through vegetation and soils/peat)
  • Nutrient recycling
96
Q

How are wetlands valuable for providing resources?

A
  • Fuelwood
  • Fisheries
  • Mammals and bird for tourism
97
Q

How are wetlands valuable for regulating conditions?

A
  • Regular supply of groundwater and so base flow of river
  • Water purification
  • Reduced flood risk
98
Q

Describe the cultural value of wetlands

A
  • Aesthetic value
  • Recreational use
  • Cultural heritage
99
Q

How do meteorological droughts impact wetlands?

A

Meteorological droughts have a major impact on wetlands; reduced interception due to less precipitation will cause vegetation to wilt and die, which in turn impacts soil nutrients levels and the rest of the complex food web.

100
Q

Physical causes of desertification

A
  • reduced precipitation
  • global warming
101
Q

How does reduced precipitation caused desertification?

A
  • As vegetation dies, the protective layer it provided for the soil will also be removed.
  • As a result, the soil will be increasingly exposed to wind and rain, which will accelerate the rate of soil erosion, leading to worsening soil conditions.
  • This may cause a positive feedback loop of worsening soil condition and vegetation death, leading to desertification.
102
Q

How does global warming cause desertification?

A
  • The rise in average climatic temperatures will increase the rate of evaporation of water moisture, especially in tropical and sub-saharan climates.
  • If more moisture has evaporated, less will be available for convectional rainfall, and so plant growth will be stunted and vegetation dies (leading to desertification)
103
Q

How does population growth cause desertification?

A
  • Population growth is the root cause of the recent increase in rates of desertification.
  • As populations increase, the demand for food, water and other resources also increases.
  • As pressure for food increases, agricultural methods change to supply the demand
104
Q

How does increased agriculture cause desertification?

A
  • cattle farming is becoming intensified resulting in large areas of forest being cut down to provide enough land for grazing.
  • Intensification of crop farming means the time between crop harvest and new planting will be reduced.
  • These practices can cause over-cultivation, trampling of vegetation and loss of soil nutrients which reduces soil fertility.
  • forests may be felled or slashed-and-burned to make room for new farms or housing, further worsening soil quality and exposing the topsoil to erosion.
105
Q

Why is low-lying land more vulnerable to water surpluses?

A

River flooding can occur along with groundwater flooding as the ground become saturated, therefore any surface close to the water table is vulnerable to flooding.

106
Q

Why are urbanised, built environments more vulnerable to water surpluses?

A

Impermeable surfaces increase surface runoff, reducing lag time and so increasing the risk of flash flooding

107
Q

Why are small basins vulnerable to water surplus?

A
  • especially in semi-arid and arid regions
  • These regions suffer from flash flooding due to very short lag times, which can be hazardous.
108
Q

Methods to mitigate and adapt to flood risk (3)

A
  • afforestation of upland areas to reduce rapid surface run off
  • restricting construction on floodplains to reduce potential economic and social losses
  • establishing temporary extra floodplains in the event of extreme weather (e.g. football pitches or parks next to rivers)
109
Q

Direct impacts of climate change on the hydrological cycle (3)

A

▪ If land and sea surface temperatures continue to rise, the period between ENSO cycles could decrease.
▪ Increasing average global temperatures would increase rates of evaporation, which could lead to potential droughts and increasing water scarcity.
▪ for some locations, a rise in average temperatures will lead to more convectional rainfall and enhanced tropical cyclone or depression intensity

110
Q

How will climate change affect inputs, stores, and outputs of the hydrological cycle?

A

Climate Change will reduce inputs, reduce stores but may increase outputs within the
hydrological cycle:

111
Q

Examples of how climate change affects water cycle inputs, stores, and outputs (6)

A

➔ Less precipitation
➔ Less water available in stores
➔ Reduced size of snow and glacier mass
➔ Water Table drops (height/ capacity of groundwater store) and Aquifer stores deplete
➔ High rates of evaporation
➔ More frequent cyclones and monsoons

112
Q

Why is water distributed unevenly?

A
  • Water is spatially distributed unevenly across the globe.
  • 66% of the world’s population live in areas which only have access to 25% of the world’s annual rainfall.
113
Q

Reasons for an increase in demand for water (3)

A

● Population growth - generally more people = more water needed.
● Growing middle class population as countries develop and industrialise, therefore increasing lifestyle and domestic demand.
● Economic growth means industrial demand may also increase.

114
Q

Reasons why supply of water cannot meet demand (3)

A

● Aquifers and deep-water wells are being dug, especially for water-intensive agriculture.
● Water tables (groundwater storage) are dropping as a result.
● Water is being extracted at a faster rate than the soil is able to recharge.

115
Q

Physical causes of water insecurity (3)

A
  • Precipitation varies across different climates: mid-latitude areas generally receive the most rainfall.
  • Topography is also significant because areas with high relief generally get more precipitation and surface runoff is greater for more inclined planes, so channel flow tends to be larger and so water can be easily stored by dams and reservoirs.
  • Geology also determines water security; permeable rocks can be infiltrated, and water can be easily stored underground.
116
Q

Human reasons for a fall in freshwater supply (3)

A
  • pollution
  • industrial activity (especially in developing countries with slack environmental laws) and population pressure (lack of treatment of sewage) are reducing accessibility to clean freshwater.
  • saltwater encroachment due to over extraction and rising sea levels (Climate Change) is further reducing freshwater stores
117
Q

Why might the price of water increase?

A

As a result of a limited supply, the price of clean water has increased in certain regions, and may increase globally in the future.

118
Q

Why is water important economically?

A
  • Water is very important in economic productivity, crop yield and manufacturing capacity.
  • Fields and grazing lands are dependent on rainwater
  • aquaculture (fish farming) has been on the rise as wild fish supplies have diminished
  • Over 20% of all extracted water is used in industries and for energy production
119
Q

Solutions to water insecurity that focus on reducing water consumption (2)

A

● Many farmers focus on storing rainwater, to use for irrigation and greywater purposes.
● There has been an increase in HEP and the generation of energy without the consumption of freshwater

120
Q

Hard-engineering solutions to water insecurity (3)

A
  • mega dams
  • desalination plants
  • water transfer schemes
121
Q

Advantages of mega dams (3)

A
  • Can provide a large volume of water
  • Can generate HEP
  • Reduces demand for groundwater
122
Q

Disadvantages of mega dams (4)

A
  • Floods land
  • Expensive
  • Countries/areas downstream suffer from lack of water
  • Water is stored on surface so gets evaporated quickly
123
Q

Advantages of desalination plants (2)

A
  • Can provide a large volume of clean water
  • Reduces demand for groundwater
124
Q

Disadvantages of desalination plants (4)

A
  • Energy intensive
  • Releases lots of CO2
  • Produces large amounts of brine as waste
  • Expensive to build and maintain
125
Q

Advantages of water transfer schemes (2)

A
  • Can provide water for areas that lack water and arid areas
  • Water can become a valuable resource for
    countries otherwise poor and undeveloped
126
Q

Disadvantages of water transfer schemes (4)

A
  • Can dry up source areas
  • Expensive
  • Lots of water evaporated
  • People relocated to construct
127
Q

What is the Water Poverty Index (WPI)?

A

The WPI is an index used to measure localised water stress, for the use of national governments to improve provisions.

128
Q

5 components that the WPI focuses on

A

▪ Water resources – the availability and quality of water
▪ Access to water – the distance from safe water for drinking, cooking, cleaning and industries
▪ Handling capacity – management, infrastructure and income
▪ Use of water – for domestic, agricultural and industrial purposes
▪ Environmental indicators – ability to sustain nature and ecosystems

129
Q

How is the WPI scored?

A

Each component is scored out of 20, giving a total score between 0 and 100 (100 meaning no water stress, 0 meaning water stress and deficits constantly).

130
Q

Which country has the highest WPI?

A

Finland (with a score of 78)

131
Q

Which country has the lowest WPI?

A

Haiti has the lowest score of 35

132
Q

ways to manage water sustainably (5)

A

● Sprinklers are by automated spray technology or advanced irrigation systems which are more efficient.
● Recycling city wastewater is a relatively cheap method of conserving freshwater supplies, especially in areas of extremely high demand. ‘Grey water’ doesn’t need to be cleaned as much to meet drinking standards
● GM crops are being developed, many are tolerant of dry and saline conditions
● Restoration of damaged lakes, rivers and wetlands to increase natural water storage
● Restoring meanders & replanting vegetation

133
Q

Ways to conserve water domestically (4)

A
  • installing smart metres
  • charging more for water during times where there is a lack of water supply
  • using eco-kettles
  • taking a shower instead of a bath
134
Q

What is Integrated Water Resource Management (IWRM)?

A
  • The IWRM approach emphasises the river basin as the logical geographic unit for strategic planning.
  • The basin is treated holistically to protect environment and ensure fair distribution
135
Q

Features of IWRM (7)

A

▪ Freedom from corruption
▪ Environmental protection of all supplies and ecosystems
▪ Food and water security for poorer people
▪ Effective dialogue between people
▪ Decentralised approach
▪ Cash recovery of schemes through effective pricing
▪ Effective regulation and planning use

136
Q

Describe the IWRM approach to groundwater management

A

-Aquifer storage and reuse
-Groundwater quality and quantity modelling

137
Q

Describe the IWRM approach to waterway management

A

-River rehabilitation
-Sustainable water allocation
-Environmental flows

138
Q

Describe the IWRM approach to integrated urban water management

A
  • Water treatment technology
  • Water sensitive urban design
  • Water harvesting and reuse
139
Q

Describe the IWRM approach to monitoring technology

A
  • Sensor technologies
  • Real time wireless monitoring and controlling
140
Q

What are the Helsinki Rules?

A

Under the Helsinki Rules there is general agreement that international treaties must include concepts such as ‘equitable use’ and ‘equitable shares’, and be applied to whole drainage basins, not single countries.

141
Q

Criteria considered for water sharing (6)

A
  • Natural factors → rainfall amounts, discharge, share of drainage basin
  • Social and economic needs → population size, welfare of people, development plans
  • Downstream impacts → restructuring flow, water tables, pollution
  • Dependency → availability of alternative sources
  • Prior use → the tricky question of existing historic rights and potential future use
  • Efficiency → avoiding waste and mismanagement
142
Q

Describe the UNECE water convention

A
  • UN Economic Commission for Europe Water Convention
  • aims to protect and ensure the quality and sustainable use of transboundary water resources
143
Q

What does the UNECE Water Convention promote?

A

The UNECE Water Convention promotes joint management and conservation of shared freshwater ecosystems in Europe and neighbouring areas.

144
Q

What does the UN Water Courses Convention do?

A

The UN Water Courses Convention offers guidelines on the protection and use of transboundary rivers.

145
Q

What does the WWF believe about water treaties?

A

the WWF says that most agreements lack appropriate enforcement and monitoring.

146
Q

Define eutrophocation

A
  • when the environment becomes enriched with nutrients, increasing the amount of plant and algae growth to estuaries and coastal waters
  • this can hinder growth underneath due to reduced access to sunlight