Water Cycle Flashcards
cryosphere
water held in ice
biosphere
global ecological system with all living beings
blue water
water stored in lakes, streams and groundwater
green water
water stored in soil and vegitiation
precipitation
movement of water in any form
evaporation
change of state of water from liquid and gas
transpiration
diffusion of water from vegetation to the atmosphere
evapotranspiration
combination of evaporation and transpiration
fossil water
ancient deep ground water from fluvial periods
store
reservoirs where water is held such as oceans
flow
movement of water as one part of the system
input
when water enters a source again
output
movement of water out of a source
flux
movement of the rate of flow between stores
what is an example of solar energy?
evaporation and transportation
what is an example of gravitational potential energy?
transformed to kinetic energy
what is the most important flux?
evaporation from oceans
what is evaportation?
water from the ground to the atmosphere
what is the flux of evaporation? number
436.5 km3/year
what is the flux of precipitation?
water from the atmosphere to the ground like rain, snow and hail
what is the flux of precipitation? number
391 km3/year
what is the flux of groundwater runoff?
throughflow like soil and bedrock
what is the flux of groundwater runoff? number
45 km3/year
what is the flux of transpiration?
vegetation to atmosphere to the biosphere
what is the flux of transpiration? number
68.7 km3/year
what are the 6 steps for convectional rainfall?
1 - sun warms earth’s surface
2 - surface warms overlying air
3 - warm air becomes less dense and rises
4 - rising air cools and decreased ability to hold moisutre
5 - cools and reaches saturation and dew point and forms around condensation nuclei
6 - clouds form and it rains and repeats
what are the 4 steps of orographic rainfall?
1 - solar energy heats up the earth’s surface
2 - air rises and reaches condensation and nuclei and forms around condensation nuclei
3 - rains on the stoff side of the mountian
4 - dry decending air fall of lee side of the mountains
what are the 4 steps of frontal rainfall?
1 - solar energy heats up surface layer
2 - cool air block causes warm air to rise
3 - air reaches saturation and dew point and forms around condensation nuclei
4 - air condensed into clouds and process repeats
what is an example of convectional rainfall?
amazon
what is an example of orographic rainfall?
Himalyays
what is an example of frontal rainfall?
UK
what is a meterlogical drought?
deficit in precipitation
what is a agricultral drought?
deficit in soil moisutre
what is a hydrological drought?
deficit in all stores
what is a famine drought?
widespread crop failure
El Nino year causing drought in Australia
- 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
- Rising ocean temps. creates convectional rainfall on coast of Peru, creating wetter conditions
- Dry air returns to Australia so less precipitation which leads to meteorological drought
La Niña
unusually cold sea surface
temperatures found in the eastern
tropical Pacific. A La Niña episode
may follow an El Niño.
what is a river regime?
measure of annual variationa in river with discharge measured in cumecs
where is the Yukon river located?
Canada
what influences the Yukon river regime in Canada?
- precipitation falls as snow
- locked in cryopshere and melts in June
- increases river discharge and into winter it freezes again
where is the Indus river located?
Himalayas
what influences the Indus river regime in the Himalayas?
- snow melt hits peak discharge in May
- June 4 month monsoon season with North shift of ITCZ
- august dry season starts
- global warming = less snow melt due to increased evaporation
what influences river regimes in the Amazon river?
- large convectional rainfall
- june peak discharge is created and takes 4 months for the tributries to catch up with the river
- winter = decreased rainfall
how long are the tributaries in the Amazon river?
2,900,000 sq meters
how can overlying soil influence river regimes?
influences time for inputs to reach the river
how can sandy soil influence river regimes?
allows infiltration to occur as it is more permeable
what are the 2 types of storm hydrographs?
flashy
delayed
what are 4 features of a FLASHY storm hydrography?
1 - steeper rising limb
2 - higher peak discharge
3 - gradual falling limb
4 - shorter time to exceed bank full discharge
what are 4 features of a DELAYED storm hydrograph?
1 - slower rising limb
2 - lower peak discharge
3 - steeper falling limb
4 -longer time to exceed bank full discharge
what are the 7 physical factors influencing storm hydrographs?
1 - climate
2 - relief and gradient
3 - overlying soils and geology
4 - vegetation
5 - size
6 - shape
7 - density
how does climate affect storm hydrographs? 5 rain
- intense rainfall over extended period of time
- soils become saturated
- less infiltration and percolation
- less throughflow and ground water flow
- increased water travelling by overland flow -> flood
how does relief and gradient affect storm hydrographs? 3
- steep gradient and relief = increased gravitational potential energy
- increase in overland flow
-> flood
how does overlying soils and geology affect storm hydrographs? 4
- if overlying soils is impermeable will decrease infiltration and overland flow
- if geology consists on non-pourus rock water cannot percolate
- increased saturation in the soil layer
- decreased infiltration -> flood
how does vegetation affect storm hydrographs? 4
- if there was a decrease in veg density there would be a decrease in interception
- decreased evapotranspiration
- increased like hood of ground being saturated and overland flow occurring
- increase the amount of water hitting the ground directly so increased soil compaction so increased overland flow
how does size affect storm hydrographs? 2
- smaller drainage basins produce more FLASHY hydrographs
- water has a shorter distance to travel to the channel flow so there would be a steeper rising limb and lag time
how does density affect storm hydrographs? 2
- is there are more tributaries it is more likely to be a FLASHY hydrograph as the flow is faster and it is more likely to make the water arrive at similar times
- increase flood etc
how can deforestation affect storm hydrographs? 4 - increase flood risk
- leads to decreased interception and evapotranspiration
- 25% of water returned to atmosphere in a healthy forest
- increase water on soil
- soils become saturated -> increased overland flow -> flood
how can deforestation in relation to decreased stem flow and throughfall affect storm hydrographs? 3 - increase flood risk
- less of a delay in water hitting the ground
- infiltration rates are less likely to cope with levels of water
- increased saturated overland flow -> flood
how can an increase in soil compaction from deforestation affect storm hydrographs? 5 - increase flood risk
- more water hitting the ground directly
- amazon had had 17% of it deforested
- convectional rainfall causes soil compaction
- less infiltration so increased OVERLAND FLOW -> flood
overtime the soil has less nutrients and so decreased ability to grow back
how can urbanisation affect storm hydrographs? - increase flood risk
- leads to an increase in areas with paved impermeable surfaces
- infiltration is not happening meaning an increase in overland flow
- paved areas provide low friction routes to drains to the river channel
- increase the levels of water hitting the ground at the same time
- increase overland flow -> flood
how can man made structures at the river increase flood risk?
- increased rainfall so increased debris in the water
- urbanised areas have river management strategies
- to increase channel flow to keep up with drainage
- eg levees have raised banks to increase the amount that the river can hold
- if flood waters rise -> water stays in place longer as debris is trapped in the river
what is a water budget?
balance between inputs and outputs
what is a surplus?
saturated soils
what is a defecit?
vegetation depleting the soil store
what is a recharge?
it follows a deficit and is where infiltration occurs
what is utilisation?
follows a surplus where vegetation uses moisture
what are 2 types of influences on drought?
indirect
direct
what is groundwater abstraction?
- process of drawing water from underground sources because demand exceeds supply from surface water stores
how can a population increase be a human influence on drought?
- increased amount of people in urban areas
- increase density and demand exceeds supply
- thin spread of resources
how can the growing middle class be a human cause of drought?
- increase number of people to feed
- increase in incomes so increasing availability of meat products
- 1kg of wheat takes 600-4,000 L of water to make
- increases water for cattle and so more drought
what are the 2 problems for groundwater abstraction?
1 - leads to hydrological drought
2 - will increase concentration of pollutants and contaminants
how can groundwater abstraction lead to a hydrological drought?
- taking of water faster than replenishment
- takes years to recharge
- decrease flow to river creating a drought further downstream
how can groundwater abstraction lead to an increase in concentration of pollutants and contaminents?
- makes water less usable and more expensive to use
- eg ARYAL sea with groundwater abstraction
what is the case study for human causes of drought?
Aryal sea
- abstraction in 1940s
- used water for food growth and manufacturing
- decreased river by 10% due to decreased flow
- increased concentration of water
what are the 5 steps of the enhanced greenhouse affect?
1 - earths surface is warmed by short UV rays
2 - 31% reflected back into space
3 - remaining UV rays are absorbed
4 - heats surface and is re-radiated by long wave infrared radiation
5 - greenhouse gasses absorbed and re-radiate as infrared radiation in all directions
how can human activity affect the enhanced greenhouse affect?
- increase combustion of fossil fuels has increased the level of greenhouse gases
- more radiation is trapped leading to increase global temperatures
what are the 4 steps of the expansion of the Hadley cell casuing drought?
1 - with global warming strength of convection of the ITCZ increases
2 - causes increase in lat movement of the cell
3 - increase number of countries experiencing high pressure weather systems
4 - increase in evap and decrease in precip so a drought will form
how is the decreasing water in the cryosphere causing drought?
- global warming means retreat of glaciers and ice sheets
- decrease in water stored in ice
- causes a drought as this meltwater goes through the river
what is the case study for the decreasing water in the cryosphere casuuing drought?
Indus river in the Himalayas
how is the semi-permanent move of the north migration of the thermal equator causing drought? 4
1 - land absorbs and re-radiates excess heat more effectively than oceans
2 - N hemisphere is warming quicker than the south
3 - ITCZ is driven by where convection currents are strongest
4 - thermal equator moves N with the ICTZ and convectional rainfall with it
how can groundwater abstraction cause a drought?
- increase pressure from rising sea levels
- increased pore water in aquifers which takes out salt water
- salt water encroachment occurs creating a drought
what is the case study for drought?
SOUTH AUSTRALIA DROUGHT 2006
- physical causes -> El Nino year
- human causes -> expansion of Hadley cell and groundwater abstraction
- impacted the Murray Darling Basin
provides 50% of the agricultural output - increased crop failure and exports
- impacted urban areas such as Adelaide with the basin at 40% capacity
what is a wetland?
an area of land that is saturated seasonally or perminantly
what % of area do wetlands cover?
10%
what are the 4 types of wetalnds?
- marsh
- bog
- fen
- swamp
what is a physical function of a wetland?
- temporary store in the hydrological cycle
- use as a water source
- recharges aquifers
- slow passages of flood waters to a river
what happens to the physical function of a wetland in a drought?
- decreased in water and vegetation cover
- increase exposure to solar energy and do not recharge aquifers
- soil baking and overland flow
what is the chemical function of a wetland?
- trap and recycle pollutants and nutrients
- bacteria breaks down pollutants and is home to aquatic species
what happens to a wetland chemically in a drought?
- increase concentration of pollutants
- decrease filtration so fish die
what is the biological function of a wetland?
- provide habitats for fish and create breeding areas
what happens to the biological function of a wetland in a drought?
- less migration and gene pool so they are less resilient to disease and so die
how can deforestation lead to a hydrological drought?
- decrease infiltration and percolation
- decrease water in the groundwater stores
- dries out and causes a drought
how can deforestation cause forest stress?
- with soil baking and compaction it causes decreased infiltration and percolation
- less nutrients in the soil
- less resistant to diseases and pests so die and less likely to recover
what are some human factors that can cause flooding?
- urbanisation
- climate change due to manufacturing
what is the main case study for flooding?
CUMBRIA - KESWICK February 2020
- 180mm of rainfall over 2 days
- in Feb = soil moisture surplus
- steep relief = increased bank full discharge quickly so flooded
how come floods are more likely to happen in winter?
- ground is already saturated so less infiltration and percolation
- increased overland flow into the main channel
- exceeds bank full discharge quickly = FLOOD
what is the second case study for floods?
BANGLADESH
- has low lying land behind coastal areas
- inputs of precipitation with meltwater from the Himalayas
- also has tropical storms creating storm surges
how can decreased stemflow and throughfall increase flood risk? 4
- decreased interception due to low levels of vegetation
- increase water hits the ground directly and soil compaction
- decrease in infiltration and percolation
- increase saturated overland flow causing a flood
how can decreased evapotranspiration lead to increased flood risk? 5
- 25% of water is returned to a healthy forest
- increased amount of water in the drainage basin
- soil layer is more likely to be saturated
- decreased infiltration and percolation so saturated overland flow beings
- will exceed bank full discharge causing a flood
how can decreased carbon sequestration lead to increased flood risk? 5 -monsoon rainfall
- increased amounts of greenhouse gasses
- increased EGHE and global temperatures
- increase in eustatic sea level rise and coastal flooding in areas such as the Maldieves
- increase in convectional rainfall due to increasing temps
- increased intensity of monsoon rainfall
what are the 3 ways in which urbanisation can increase flood risk?
1 - change in land use
2 - increased requirement for agriculture
3 - urban heat island effect
how can a change in land use make urbanisation increase flood risk?
- increase in impermeable surfaces such as tarmac and concrete
- decrease in infiltration as overland flow due to low friction routes
- increase the amount of water hitting the channel at similar times as exceeds bank full discharge
how can an increase in requirement for agriculture make urbanisation increase flood risk?
- increased requirement for deforestation
- make new cattle ranch farms to feed the population
- increase need for products considered part of the Western diet
- due to increase incomes causing soil compaction etc
how can the urban heat island effect increase flood risk?
- the large amounts of concrete and tarmac which is densely packed impermeable surfaces
- low albedo surfaces re-radiate it and absorbs it rather than reflect
- the growing global middle class leads to air conditioning and car usage which increase pollutants and greenhouse gasses
- densely packed heat escapes when difficulty
how can soils of nutrients from fertilisers and agricultural land impact flood events?
- increase of concentrations of nitrogen into standing bodies of water due to the increased overland flow
- leads to excess plant growth and algae blooms
- leads to EUTRIPHACATION
- dense plant growth blocks sunlight and causes species to die due to no light in the water
- creates a dead zone
how can physical, chemical and biological functions of wetlands are all enhanced due to the increased availability of water impacts flood events?
physical function
- improved due to more infiltration and percolation
chemical function
- allows and increase in filtration and bacterial breakdown of surface waters
biological function
- more habitable for a greater variety for species and increased biodiversity
what is the economic negative of socio-economic impacts if flood by humans?
- flood events can damage buildings
- can decrease economic output of businesses
- 2015 Cumbria floods with the McVities stopped producing biscuits
- in LIC can affect quality of agriculture and can affect crop yields.
what is the social negative of socio-economic impacts if flood by humans? Death
- flood waters can lead to deaths in LIC + NEE countries
- 90% of deaths caused by flooding in Asia
- knock on affects to local areas and a loss in value of residential proporty
what is a social negative of flood by humans? 3
- flood waters in LICs can be damaging and can increase the volume of poorly disposed treated waste
- flood waters carry contaminants and can create diseases
- healthcare services could become unsustainable strain
what are the future flood trends of Amazon, Brazil?
- increased convectional rainfall
- increased saturation of soils so increased overland flow
- increased floods
what are the future flood trends of Northen Canada and Siberia?
- thawing cryoshpere will increase melt waters and inputs and will overwlem the drainage basin
what are the future flood trends of Bangladesh?
- increases in sea levels will increase the risk of coastal flooding
- increase tropical storms and monsoon rainfall
- more frequent and intense storms
how does the expasion of the Hadley cell contribute to future drought trends?
causes more dry decending high pressure weather systems to cover more areas of Southern Europe
how can a decrease in frontal rainfall in mid lats decrease temperature different between polar and tropics?
- less energy for rainfall
- METEROLOGICAL DROUGHT
what is water stress?
when society has less than 1,700 m3/person
what is water scarcity?
when a society has less than 1,000 m3/person
what is water insecurity?
when supplies cannot be gurenteed
what % of water do humans use?
60%
what % of the population has no safe drinking water?
15%
what % of water is avaliable for use?
1.5%
what % of water is avaliable through surface water stores?
1%
how can an increase in global populations lead to water scarcity?
- increase demand for food and for agriculture
- more farms to keep up with demand
- more deforestation
- decrease in biotic pumping and soil compaction leading to no recharge of aquifers
how can a growing global middle class lead to water scarcity?
- increase of people having a western diet
- increased running water in homes
- increase requirement to manufacutre white goods
- more co2 released during manufacturing
- more EGHE and expansion of the hadley cell causing drought
how can an increase in industrialisation lead to water scarcity?
- increase advancment of technology used in NEEs
- increased requirement of energy in electricity
- increased construction of dams to create electricity
- reduced flow downstream causing drought
how can the pollution of groundwater and surface water store supplies influence water insecurity?
- caused by aggressive agriculture
- more in developing countries where they have weak water treatage and gov
- causes areas of water to be polluted
what is the case study for a NEE having humans causing water insecurity?
CHINA
- 1/3 of all rivers and coastal zones polluted
- toxins released into the river
- 805 of recent deathas caused by toxins in the water
how can humans overabstracting surface and ground water stores cause water insecurity? Extracts in a year
- 2025 predicted that extracts will be 5,000km a year
- 2/3 of this will be agriculture
- 90% in developing countries
- due to demand increasing so need to find the supply
- increased growing growing middle class
how can the extensive ground water pumping lead to saltwater encroachment?
- seaward movement of freshwater can decrease salt water encroachment at coastlines
- pore water pressure within aquifers also leads protects against swe
- global warming is increasing sea levels and allows for more slatwater to contaminate the sea
how can climate detrrmine the global distribution of water supply?
- mid lats and ITCZ get most rainfall (convectional and frontal)
- seasonal variations can occur creating monsoon rainfall
- ENSO cycles can also affect supply
how can tupography influence distribution of water?
- it is an area with high relief and runoff giving water to be mnore widley distributed
- comminity located on the stoff side get water
- community located on Lee side get water insecurity
what are the 2 reasons for conflict with the River Nyle?
1 - decreasing supply
2 - increased demand and population
why is there a decreasing supply for water in the River Nyle?
edge of the Hadley cell so expirence large amounts of high pressure weather systems
what is the population expected to rise to by 2075 in Egypt? (River Nyle)
200 million
why is there conflict at an international scale with the River Nyle? 4
- the Nyle waters agreement allocated 55bn m3/water a year to Egypt
- heavily reliant on the Nyle (97%) for cotton production and power
- conflict rose with the creation of a dam in 2011
- would slow channel flow for Egypt and they threatened military action
what % of water does the River Nyle provide for Egypt?
90%
how much water was Egypt allocated with the river Nyle waters agreement?
55 billion m3/year
what are the 2 reason for conflict in the Colarado river?
1 - decreasing supply
- increasin demand and population
why is there a decrease of supply in the Colarado river?
- been in drought since 2000
- global warming decreased inputs and increased outputs
- dam construction decreased the flow of water
why is there a increasing demand for water and increasing population in the Colarado river? Arizona
- Arizona population set to double 2010-2030
- increase requirement for food so uses water
- 1.4 million ha of farmland which is responsible for growing 155 of the crops
- there is a precipitation deficit
what x is the population of Arizona set to rise by 2010-2030? (Colarado river)
2
how may million of ha land is farmland in Arizona? (Colorado)
1.4 million ha of land
why is there conflict at a reigonal scale for the lower basin of the Colorado river?
- 1922 21 bn m3/year water was allocated
- discharge was reduced by 15% of flow
- decreased inputs into the basin and with the construction of dams
- southern areas think that the N have been given more and so caused tension
why is there conflict at international level with the Colorado river? Mexico
- 1922 Mexico were allocated 1.85 billion m3/water a year
- 90% of water was extracted before reaching Mexico
- 10% of water was unusable with high pollutanta
what is physical scarcity?
when demand exceeds supply that is avaliable
what is economic scarcity?
when the supply is theoreitcally inadequate due to the lack of investment in water infastrucutre
what are the 3 influences on the price of water?
1 - cost of supply
2 - changes in demand
3 - privitisation
how does the cost of supply influence the price of water?
- requires water infasterucutre to be developed
- give a running cost which is determined by the distance the water travels and the terrain that it has to travel
where does the water from Californa travel through? distance and terrain?
250 miles
San Gabriel mountains
why has changes in demand influenced the price of water?
- increased the demand so the suppliers charge more
- demand will increase due to the
>population increase
>increasing global middle class
> increasing demand for agriculture
> increasing industrilaisation
how has privitisation influenced the price of water?
- moves of water companies from government ran to TNC
- part of SAPs due to IMF and WB
- TNCs are profit driven and make investments to increase extraction
- increase cost to the customer
how do dams manage water differently? GIRD dam
- GIRD with the dam on the Nyle boarder of Sudan
- runs through Ethiopia 45% have electricity
- is in a mountinaous terrian so loses little water
- increases inputs
-decreases outputs
how can the desalination with the tratments of fresh from salty water to create drinking water manage water supply?
- treats both types of water
- Syngapore withe the Mariana Plant uses reverse osmosis to generate drinking water
- 7% of the water is created this way
- is a consistent supply
- has a small drainiage basin so output is low
how can water transfer schemes manage water differently?
- china has created the N/S water diversion
- $80 billion tunnel that transfers water from the S->N
- 100 million more people have access to water
- has 18 powerhouses
- 75% of water in Beging comes from this
what is sustainable water managment?
meeting the needs of the people without compramising ability of future generations
what is water conservation?
using less water to decrease the relience on the extraction of ‘new water’
what is grey water recyling?
re-using or reclaiming water from taps and sinks
where is grey water recyling being used?
Isreal and Adalain
what % of agriculture uses grey water recycling?
40%
what is drip feed irrigation?
less exposure of water to direct sunlight so less is lost to evaporation
what is the case study for drip feed irrigation?
SINGAPORE -> by 2060 water demands x2 to 860 million m3/year
- aim to have 85% of water demands covered by NEW WATER
what is the UNECE?
aims to protect to ensure quality and quantity and sustainable use of transboundary water sources
what does the UNECE do?
- facilitates cooperation
- provides intergovernmental platform for day to day development
what is the aims of Helsinki rules?
asserts the rights of al boundry nations to equitable shares
what is the case study for Helsinki rules?
cashmere with the river Indus:
- created shares for all of them
what is the aim of the EU water framwater directive?
establishes principles for the management of trans-boundary water in between the EU and member states
what is article 3?
creation of an international district for river basins that cover more than 1 territory
what happens if a district fails to keep water in the corrct condition?
they get fined
