Water Flashcards
1
Q
What is the difference between flows and fluxes?
A
Flows are movements of water from one system to another, fluxes are a measurement of the rate of flows between stores
2
Q
Which words are used to describe water moving in/out of a store?
A
Inputs and outputs
3
Q
Which is the largest hydrological store and what % of total water does it take up?
A
Oceans, 96.9%
4
Q
What is the hydrological cycle driven by?
A
Solar (e.g. evaporation/precipitation) and gravitational potential energy
5
Q
What is the order of fluxes from largest to smallest?
A
Evaporation –> precipitation –> groundwater runoff –> evapotranspiration
6
Q
What type of system is the global hydrological system and what does this mean?
A
Closed system, transfer of energy but not matter between system and its surroundings
7
Q
What type of system is the local (drainage basin) hydrological system and what does it mean?
A
Open system, volume of water in drainage basin isn’t fixed over time
8
Q
What are the 7 flows of water within a drainage basin?
A
- Interception
- Infiltration (soil)
- Throughflow
- Percolation (rocks)
- Groundwater flow
- Overland flow
- Saturated overland flow
9
Q
What are the 3 types of interception (precipitation stopped by vegetation)?
A
- Interception loss
- Throughfall
- Stem flow
10
Q
What is the 1 input and 3 outputs of water within a drainage basin?
A
Input: Precipitation
Outputs: Channel flow, evaporation, transpiration
11
Q
What are the 3 types of precipitation and where is each type found?
A
- Convectional - tropics e.g. Amazon
- Orographic - mountains e.g. Himalayas
- Frontal/cyclonic - mid latitudes e.g. UK
12
Q
Describe the process of convectional rainfall
A
- Solar energy from the Sun warms the Earth’s surface
- Earth’s surface warms overlaying air
- Air expands, becomes less dense, and rises
- Rising air cools, reducing ability to hold water vapour
- Water vapour condenses as air reaches saturation and dew point
- Clouds form as condensation forms around condensation nuclei and process continues until rain falls
13
Q
Describe the process of orographic rainfall
A
- Air forced to rise up stoss side of mountain
- Air cools, reducing ability to hold water vapour
- Air reaches saturation and dew point
- Condensation forms around condensation nuclei
- Clouds form on stoss side where rain falls
- Rain shadow formed on leeward side
14
Q
Describe the process of frontal/cyclonic rainfall
A
- As warm and cold air masses meet, warm air forced to rise over cold air mass because less dense
- Air cools and reduces ability to hold water vapour
- Air reaches saturation and dew point
- Condensation forms around condensation nuclei
- Process continues and rain falls
15
Q
What are the 3 river case studies for river regimes and where are they located?
A
- River Yukon - North America
- Amazon River - South America
- River Indus - India
16
Q
What does the River Yukon’s river regime look like?
A
Stays constant until river discharge increases then decreases
17
Q
Why does the River Yukon’s river regime stay constant until river discharge increases then decreases?
A
- Precipitation falls as snow and stored in cryosphere
- April: Temp. increases so water moves from cryosphere to hydrosphere and travels to river via OLF and precipitation falls as rain so steep increase in river discharge
- May: Temp. increases so ice melt enables infiltration, percolation, groundwater flow which feeds base flow as temps. drop again
18
Q
What does the Amazon River’s river regime look like?
A
Relatively stable but increases and then decreases
19
Q
Why does the Amazon River’s river regime stay relatively stable but increases and then decreases?
A
- Spring: Sun directly overhead so creates convectional rainfall due to ITCZ
- June: Peak discharge reached but takes 4 months for tributaries to contribute due to large basin
- Autumn: Earth tilts away from Sun in S. hemisphere so decreased convectional rainfall as ITCZ has shifted north
20
Q
What does the River Indus’ river regime look like?
A
Slight increase, levels off, increases again to reach peak discharge, then decreases
21
Q
Why does the River Indus’ river regime have 2 peaks and then decreases?
A
- April: Temp. increases so river fed by snow melt from Himalayas so increased river discharge
- May: Hits initial peak discharge due to drainage basin’s topography
- June: Monsoon season associated with Northwest shift of ITCZ so increased convectional rainfall and steep increase in river discharge due to saturated soils
- Dry season starts so discharge rapidly drops with increased evaporation and water locked in cryosphere in Himalayas again
22
Q
What 3 ways can humans impact flows and fluxes in a drainage basin?
A
- Dam construction
- Urbanisation
- Cloud seeding
23
Q
What is the case study for dam construction impacting flows and fluxes in a drainage basin?
A
Dams in the Niger Delta
24
Q
By what % have upstream dams in the Niger Delta reduced flows into the delta?
A
15%
25
How does dam construction impact flows and fluxes in a drainage basin?
Reduces evaporation and precipitation when wetlands are drained and woodlands are deforested so less inputs
26
What is the case study for urbanisation impacting flows and fluxes in a drainage basin?
2015 flood of York (River Ouse)
27
How does urbanisation impact flows and fluxes in a drainage basin?
Creates more impermeable surfaces e.g. concrete which reduce infiltration, throughflow, percolation, groundwater flow and increase OLF which decreases lag time and increases peak discharge
28
What is the case study for cloud seeding impacting flows and fluxes in a drainage basin?
Used in 2015 in Texas to reduce impact of drought
29
How does cloud seeding impact flows and fluxes in a drainage basin?
Substances released into air which act as condensation nuclei and change the amount/type of precipitation
30
What are the 2 types of storm hydrograph?
Flashy and delayed
31
What do you always need to link to when talking about storm hydrographs?
Lag time and peak discharge
32
What 3 physical factors create a flashy storm hydrograph?
1. Climate (intense rainfall)
2. Relief (steep topography)
3. Geology (non-porous rocks)
33
How does intense rainfall lead to a flashy storm hydrograph?
Soil moisture holding capacity exceeded so less infiltration, throughflow, percolation, groundwater flow so saturated OLF so decreased lag time and more water arriving at river at same time so increased peak discharge so flashy storm hydrograph
34
How does a steep topography lead to a flashy storm hydrograph?
Increased gravitational potential energy so water travels faster via OLF so decreased lag time and increased peak discharge so flashy storm hydrograph
35
How do non-porous rocks e.g. igneous rocks lead to a flashy storm hydrograph?
Less percolation and groundwater flow so increased OLF so decreased lag time and increased peak discharge so flashy storm hydrograph
36
How can a PAD about storm hydrographs be linked to flood risk?
Higher/lower risk of flooding as peak discharge is more/less likely to exceed bankfull discharge
37
How does deforestation influence storm hydrographs?
Less vegetation so less interception and transpiration so soil saturated more quickly so less infiltration, throughflow, percolation, groundwater flow so water travels more quickly via saturated OLF so decreased lag time and more water arriving at same time so increased peak discharge (long term nutrients washed away so less vegetation)
38
What % of water is returned to the atmosphere by the evapotranspiration of vegetation?
25%
39
What is the linked evaluation for deforestation influencing storm hydrographs?
Increased environmental awareness so increased consumer demand surrounding protection of habitats so companies investing into afforestation programmes
40
Which company decided to plant 3 trees for every 1 tree they cut down?
Velvet
41
What is the linked evaluation for urbanisation influencing storm hydrographs?
Better environmental planning so more infiltration, throughflow, percolation, groundwater flow so longer lag time and decreased peak discharge as water reaching river at different times
42
Which car park has a grid over pebbles instead of concrete?
Jodrell Bank car park
43
How do bridges influence storm hydrographs/flood risk?
Debris blocks channel so channel flow volume increases upstream so peak discharge more likely to exceed bankfull discharge
44
What is the case study for bridges influencing storm hydrographs/flood risk?
2004 Boscastle floods
45
What is meant by a positive and negative water balance with examples?
Positive: Inputs > outputs e.g. UK
Negative: Outputs > inputs e.g. Sahel
(Inputs = precipitation, outputs = evapotranspiration, runoff)
46
What does soil moisture budget show?
How much water is held within soil store in a drainage basin
47
What are the 4 stages of a soil moisture budget?
1. Soil moisture surplus (inputs > outputs)
2. Soil moisture utilisation (outputs > inputs)
3. Soil moisture deficit (outputs > inputs)
4. Soil moisture recharge (inputs > outputs)
48
Explain how El Nino causes drought in Australia
1. Westward trade winds reverse so cold water off coast of Peru replaced by warm water and warm water off coast of Australia replaced by cold water
2. Rising ocean temps. creates convectional rainfall on coast of Peru, creating wetter conditions
3. Dry air returns to Australia so less precipitation which leads to meteorological drought
49
What is an example of a drought caused by El Nino?
Big Dry 2006 in Australia
50
Which current provides cold, nutrient-rich water to Peru and by what % are fish stocks in Peru reduced by during El Nino?
Humbolt current, 45% reduction as current can't reach the surface
51
Explain how La Nina causes drought in Peru
1. Stronger westward trade winds from Peru to Australia
2. Warmer water off the coast of Australia and colder water off coast of Peru
3. Convectional rainfall in the west so increased risk of flooding
4. Dry air returns to Peru via a walker loop which creates drier conditions with less precipitation which leads to meteorological drought
52
How does increased agriculture related to increasing global pop. cause a water deficit (indirect)?
Increasing global pop. e.g. in China so larger global middle class so increased demand for meat production which uses a lot of water
53
How many litres of water is needed to produce 1kg of meat?
5,000-20,000L
54
How does increased manufacturing related to increasing global pop. cause a water deficit (indirect)?
More production in S.E Asia and Africa due to global shift and westernisation ideology expanding so increased manufacturing and demand for water e.g. fracking
55
What is the case study for drought in a developed country?
The Big Dry 2006 in Australia
56
What is a physical and human reason for drought in Australia (developed)?
Physical: El Nino
Human: Anthropogenic climate change
57
How does anthropogenic climate change cause drought in Australia (developed)?
1.Consumption of fossil fuels generated EGHE which impacted Hadley cell by expanding it towards polar regions
2. Reduced temp. gradients between the pole and tropics due to rising surface temps. so less energy for mid-latitude storm systems
3. Increased frequency of warm, dry conditions in Australia so meteorological drought
58
What is the case study for drought in a developing country?
The Sahel
59
What is a physical and human cause of drought in the Sahel (developing)?
Physical: Geographic location
Human: Development level
60
How does geographic location cause drought in the Sahel (developing)?
1. In a transitional climate zone so 86% rainfall within summer months when rates of evaporation are highest
2. Maximised water loss so level of rainfall varies significantly from year to year (100-800mm/year) so can experience years of hydrological drought
61
How does low levels of development cause drought in the Sahel (developing)?
1. Low levels of development and significant pop. growth so increased demand for low-cost food and energy
2. Overgrazing and deforestation to increase farming for growing pop.
3. Inappropriate agricultural management caused desertification
4. Reduced productivity of land and soil moisture so increased potential for agricultural drought
62
What is the case study for groundwater abstraction causing drought?
Aral Sea
63
How did groundwater abstraction in the Aral Sea lead to drought?
1. Soviet Union removed water from 2 main rivers which fed Aral Sea for use in irrigation of crops for cotton manufacturing
2. Inputs exceeded by outputs so decreased water volume to 10% of its original size so drought
64
Describe the process of the natural greenhouse effect
1. Earth's climate driven by short-wave solar radiation e.g. UV
2. 31% of solar radiation reflected by clouds back into space
3. Remainder absorbed by Earth's surface/oceans and energy re-radiated back to space as long-wave infrared radiation
4. Greenhouse gases in atmosphere absorb infrared radiation and re-radiate it in all directions, trapping heat in atmosphere
65
Describe the process of the enhanced greenhouse effect
1. Human interference accelerating natural greenhouse effect by increasing conc. of greenhouse gases in atmosphere
2. Increased amount of long-wave infrared radiation trapped within atmosphere, increasing global temps. further
66
How can the expansion of the Hadley cell cause drought?
Dry air pushed further out so less energy for mid-latitude storms and frontal rainfall so storms/rainfall is less frequent so meteorological drought
67
How can the movement of the ITCZ cause drought?
Northwest movement takes convectional rainfall with it, leaving regions such as the Sahel with less rainfall so meteorlogical drought
68
Describe a physical function of wetlands and how it reduces flood risk
1. Act as a store for water and slowly release water to restore aquifiers and contribute to larger bodies of water
2. More water in groundwater store so supports groundwater flow
3. Longer lag time and decreased peak discharge so decreased flood risk
69
Describe a chemical function of wetlands
1. Wetland traps and filters contaminants which bacteria break down
2. Nutrients are recycled so water quality is improved (used as a water source for organisms)
70
Describe a biological function of wetlands
Increase biological productivity by providing habitats for birds/fish
71
Which drainage programme decreased the biodiversity of vegetation, birds, fish, and insects (wetlands)?
Southern Iraq drainage programme
72
Describe how drought impacts forests (could also link to flood risk)
1. Causes forest stress so plants will prioritise growth over health
2. Weaker trees with less energy so decreased vegetation cover
3. Less interception when rainfall occurs so more direct hits to soil and more soil compaction so more OLF (flood risk link)
4. More soil erosion which washes away nutrients and reduces future forest health
73
Which droughts led to a less dense tree canopy (drought impacting forests)?
Amazonian droughts 1995-2005
74
What are the 3 ways deforestation can increase flood risk?
1. Less interception so less stem flow and throughfall so more soil compaction etc.
2. Less interception so less interception loss so less evapotranspiration so water remains in drainage basin so more soil moisture surplus so water holding capacity exceeded so saturated OLF etc.
3. Less vegetation cover so less shade so more exposure to solar energy so bakes soils so less infiltration etc.
75
What are 3 ways urbanisation can increase flood risk?
1. More impermeable surfaces e.g. concrete so no infiltration etc. (+ drains provide direct route to river)
2. Larger pop. density so higher demand for food and need for agricultural land so more cattle ranching so more soil compaction etc.
3. Urban island heat effect - dark surfaces e.g. tarmac have low albedo so absorb heat and re-radiate it so (convectional rainfall explanation) so more input so flooding
76
How much more rainfall is there in urban areas as a %?
15%
77
What is an environmental positive of flooding?
Wetlands are better able to perform chemical function so more plant growth and filtration so better quality of water with decreased conc. of contaminants
78
What is an environmental negative of flooding?
Flooding causes soil erosion and leeching of nutrients from fertilisers so (eutrophication explanation from biology)
79
What is the mid-latitude case study for flooding and its LE?
UK flooding Feb 2020, LE: Urbanisation
80
What was February on a UK scale since records began in 1910 and why was this the case (flooding)?
Wettest February, storms Ciara, Dennis, and Jorge, significant rainfall in previous 9 months so soils were saturated and couldn't retain as much water
81
As a result of storms Ciara, Dennis, and Jorge, how many properties were flooded in England and how much was estimated in insurance pay-outs?
3,300, £360 million
82
What is the tropics case study for flooding and its LE?
Bangladesh 2017 floods, LE: Removal of mangroves
83
Why did the 2017 Bangladesh floods occur?
Monsoon season, low-lying land, seasonal melting of snow and ice in Himalayas, exposed to both river and coastal flooding
84
How many people were confirmed dead and by what % did the price of rice increase by as a result of the 2017 Bangladesh floods?
1,300 confirmed dead, 30% increase due to farmland flooding
85
What is the temperate case study for flooding, what % of the GDP has there been in economic damage, and what disease have areas become infested with as a result of flooding?
2022 Pakistan floods, 12% of GDP in economic damage, malaria
86
What 3 things will climate change impact?
1. Precipitation in the tropics
2. Volume of cryosphere
3. Frequency of high pressure weather systems
87
How will climate change impact precipitation in the tropics (can link to flood risk)?
Increased precipitation in the tropics due to more convectional rainfall as warmer air expands... (convectional rainfall explanation)
88
How will climate change impact the volume of the cryosphere (can link to flood risk)?
Decreased volume as increased temps. melts ice and snow so more meltwater and surface runoff so shorter lag time and increased peak river discharge
89
What is application for climate change impacting the volume of the cryosphere?
Himalayas has the 3rd largest amount of glacial ice
90
What is a linked evaluation for climate change decreasing the volume of the cryosphere?
Less likely to be significant in the future as continued melting decreases store's volume over time
91
How will climate change impact the frequency of high pressure weather systems?
More evaporation at equator so air forced further out, causing expansion of Hadley cell so more high pressure weather systems and less frontal rainfall in Sahel as less of a temperature gradient between air fronts --> increases likelihood of meteorological drought
92
What is a linked evaluation for climate change increasing the frequency of high pressure weather systems?
Difficult to determine whether drought is caused by physical or human factors e.g. Sahel - pop. growth, unsustainable agriculture, desertfication
93
Water stress definition
People who have access to less than 1700m3
94
Water scarcity definition
Imbalance between supply and demand for water - below 1000m3/person
95
By what year could India's demand exceed supply by 50%?
2030
96
What are 4 causes of water insecurity related to demand?
1. Larger global pop.
2. Larger middle class
3. More manufacturing
4. More agriculture
97
What are 3 causes of water insecurity related to supply?
1. EGHE causing expansion of Hadley cell
2. El Nino/La Nina
3. Transboundary water disputes
98
What 3 things influence the price of water?
1. Cost of supply
2. Demand
3. Privatisation
99
How does cost of supply influence the price of water?
Requires infrastructure e.g. pipelines, maintenance with running/staffing costs, treatment and quality costs, varies depending on distance - places with high cost of supply have increased price of water
100
How many miles is California from the Colorado River and how does this compare to Manchester (cost of supply influencing price of water)?
250 miles, water companies in Manchester can source water in nearby peak/lake districts
101
How does demand influence the price of water?
Pop. growth means there is a larger middle class so more manufacturing
102
Between what years is Arizona's pop. expected to double and how many litres of water is needed to produce 1kg of meat (demand influencing price of water)?
2010-2030, 5,000-20,000L
103
How does privatisation influence the price of water?
Private company looks to increase efficiency and profit by investing in infrastructure which increases price of water due to better services
104
What is an example of a company/TNC that purchased a privatised water supply (privatisation influencing price of water)?
CityWater in Tanzania due to water supply being privatised by World Bank
105
What is the case study for international conflict over a water resource?
River Nile
106
Which country did the Nile Waters Agreement allocate the majority of water to and gave a veto of development on the Nile to?
Egypt
107
What % of Egypt's water supply comes from the Aswan Dam and what is it a major exporter of?
97%, cotton
108
Which country doesn't accept the Nile Waters Agreement and when did they start building GERD with the support of Chinese banks and engineers?
Ethiopia, 2011
109
What % of Ethiopia's pop. has electricity and how much will GERD increase Ethiopia's current electricity output by?
45%, will quadruple current electricity output
110
Why does Egypt disagree with GERD and when did they threaten to sabotage the dam?
Fear that there will be increased water insecurity due to decreased flow of water downstream, 2021
111
What is the case study for national conflict over a water resource?
Colorado River
112
When was the agreement over the Colorado River signed and which states were allocated more water?
1922, Southern states allocated more than Northern states
113
What % has the EGHE reduced the volume of water storage in the Colorado River to and why has this created tensions within the USA?
48%, lower basins have less agricultural productivity and feel that the upper basins are getting too much water
114
What are the 3 hard engineering strategies to solve water insecurity?
1. Dams
2. Desalination plants
3. Water transfer schemes
115
How do dams solve water insecurity and what is an example?
Increase the store of water in the reservoir behind the dam, e.g. GERD in Ethiopia
116
What is a linked evaluation for dams solving water insecurity and what is an example?
Could increase water insecurity downstream e.g. GERD and Egypt
117
How do desalination plants solve water insecurity, what is an example, and why is it sustainable?
Convert saltwater/freshwater into drinkable water using reverse osmosis, e.g. Singapore Keppel Marina plant, consistent supply as when heavy rain reservoir water is treated but when drought seawater is treated
118
What is a linked evaluation for desalination plants solving water insecurity?
Energy-intensive so more CO2 emissions and brine is a byproduct which is disposed of back into sea and damages marine ecosystems
119
How do water transfer schemes solve water insecurity and what is an example?
China North-South water transfer scheme is a mega tunnel that transfers water from south to north with tough environmental measures to ensure high water quality
120
What % of Beijing's water comes from the China North-South water transfer scheme?
73%
121
What is a linked evaluation of the China North-South water transfer scheme in solving water insecurity?
Cost to those living in southern rural areas as 345,000 displaced to create a larger reservoir
122
What are the 3 water sharing treaties?
1. EU Water Framework Directive
2. Helsinki Rules
3. UNECE
123
What does the EU Water Framework Directive do, what happens if a country fails to keep its water in the correct condition, and what is the treaty's aim by 2015?
Establishes principles for management of transboundary water in the EU, country can be fined, groundwaters need to be 'not polluted'
124
What is a linked evaluation for the EU Water Framework Directive and what % of water bodies have declined in the Oder River Basin since 2015?
Not enough is being done to prevent pollution from agriculture and illegal water abstraction, 29%
125
What do the Helsinki Rules do?
Asserts rights of all bordering nations to equitable share in water resources, taking into consideration past usage and demand, and orders protection of resource by bordering nations
126
What is a linked evaluation for the Helsinki Rules?
Difficult to monitor/enforce across different nations
127
What does the UNECE do, and what is an example of when it facilitated cooperation?
Aims to protect and ensure quality, quantity + sustainability of transboundary water sources and facilitates cooperation, cooperation of hydrologists from Afghanistan and Tajikistan to monitor Amu Darya river
