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Water 2.1... - Coggle Diagram

- - - - Can hold more vapour and warm dry air hangs above the land
  - - - 1976 UK drought
        
        describe the position of the polar jet stream
        
        The jet stream position is extremely higher north of the UK then predicted. Instead of hovering over northern Scotland, its reaching 60 degrees latitude. The prominence of the jet stream brought extreme high pressure conditions over the UK.
        
        The jet stream was stuck in position over the UK, sustaining significant anti-cyclonic conditions over a substantially longer period of time then expected.
        
        significantly far north, reaching 60 degrees latitude North. The enabled the jet stream to drag in air from the east and south in huge quantities, only to drop the high pressure weather over the UK. The air was warm and dry as it had been pulled in from over land, therefore, instead of the air cooling and condensing, the air was hel above the UK and retained its warmth, resulting in higher temperatures and adding to the hydrological drought.
        
        What effects did the Drought have on the rainfall totals?
        
        The majority of the UK is approximately 85%-50% less than the average of the rainfall totals
        
        We can acknowledge that the southern areas of the UK are far below average <50%, covering all of the south west & south east, the midlands, wales and eastern areas lie Lincolnshire
        
        Hydrological Drought and rainfall shortages
        
        the drought from 1974-76 effected the entire of western Europe
        
        45 consecutive days without rain
        
        jet stream was over 65 degrees North latitude, North of the UK. Pulling in warm, dry air from over Europe
        
        exceeded 32 degrees for a week
        
        water reserves and stores fell below crucial levels, causing serious issues
  - - - regular short term alteration to the climate causes both deficit and excess in the drainage basin
      - reversed of normal conditions in the walker cell
    - - Trade winds weaken in the west pacific across Australia & Indonesia - this means the warm water that is usually in the wester pacific can flow east towards South America - warm water produces evaporation which creates low pressure off Peru and Chile - warm water, heats the air above it which rises, cools, condenses and then clouds form and precipitation occurs - this rainfall is heaviest over the Andes mountain range due to extra effect of orographic rainfall and the seeder-feeder mechanism causing flash flooding in Peru and Chile and Bolivia - the winds weakening also blocks the cold humbalt current so fish stocks are reduced in the eastern pacific - low pressure is created in the east, high altitude winds now create high pressure in the western Pacific - western pacific experiences cold water flows. Common droughts failure of monsoon rain
  - - - 30% of Australians experience hydrological droughts every year
      - Reservoirs fell by 40% of their capacity - hydrological drought - Murray River was significantly emptier than average
      - The El Nino reversal of conditions in the Walker Cell subsequently caused extreme deficit in the south eastern drainage basin of Australia causing significant droughts, associated with long-term climatic changes.
      - El Nino - serious deficiency - rainfall totals within 10% of values recorded for the last 3 months
      - Rainfall was 40-60% lower than average over a longer period of time
      - The 'big dry' is thought to have been associated with long-term climatic changes, leading to warmer temperatures an gradual drier climates for south and eastern Australia. The presence of high pressure weather conditions is an addiction to the drought
    - - long term climatic changes - 1996-2007
      - Gradual increasing temperatures drier conditions over a decade- each summer December to February
  - - - The accessibility to unlimited water supplies is higher then ever before, resulting in the consumption of water to increase in correlation to the loose restricts while the population around the globe gets higher - 8 billion
      - Sewage systems have noticeable effect on water demand
      - Global water consumption only increases with the addition of population
      - The more affluent idealise that water of any supply is unlimited all day 24/7 every year - carless use and unnecessary running and consumption just causes complication
    - - Ogallala aquifer - Texas to S.Dakota - 90-150cm a year is being lowered - will effect grain price in future
      - Water is required for..
        
        Crop processing
        
        food distribution
        
        Crop cultivation
      - Indus river - home to the largest irrigation system in any drainage basin - Pakistan - artificial watering of crops
      - Irrigation is responsible for <90% of water withdrawn from available sources. A very popular use in semi-arid regions
      - large scale MNC's like Coca-Cola require mass water supplies that can exceed the capability in some places - e.g. Plachimada reported water shortages soon after CC implemented 6 new weels for factory use, and could not support their business and factory
        
        Continued protests and litigation eventually helped the people of Plachimada to shut down the factory in March 2004.
        
        Plachimada - Palakkad district in India
    - - Industrialisation 1900's - increase in industry meant more water was necessary
      - Huge user due its large scale (global) users which require waters a vital factor for industrial procedures
      - Industrial products - USA in 1980 - $2 trillion USA in 2011 - $18 trillion
      - water supplies are struggling to maintain and sustain supplied to MNC's that rely on their store
  - - - Describe changes in the extent of the Aral Sea between 1960 and 2009
        
        Shrunk over the 49 year period - dried up on the general pattern of east to West of the sea, this can be due to the depth of lake is different areas. Significant loss of water as the sea has shrunk.
        
        Homogenous (whole) has declined significantly - from a substantial amount to almost scarce.
        
        Approximately 41,400 km2 - homogenous rea in 1960 / Approximately 300km2 - fragmented area in 2009
        
        The differ in sea area has accelerate post 2000
      - What caused the Aral sea to shrink?
        
        Cotton growing in Uzbekistan on a very large scale - demands vast quantities of water - the Uzbeks obtained water from the two rivers that feed into the Aral, therefore once they were being drained the volume of water being fed into the sea was lacking on a long term basis.
        
        Intercepted channel flows - drained them - and used the water to sustain the huge cotton schemes that progressed the Uzbeks economy but recessed their source of water.
        
        Overproduction of cotton in a water scarce region (desert/semi arid), without considering the ecosystem its being built upon. - wastage & runoff wasting water as it gets evporated
        
        Human production has negatively impacted the ecosystem - 160 of the 310 birds - 32 out of the 72 mammals - 24 fish species remain
        
        The area is now more prone to greater extreme's of temperatures
        
        Struggling subsistence farmers - grow food for themselves & their family
        
        Adding pesticides has contaminated the water in some places, meaning fresh water that supplies families is less clean, also has acidified water killing of some fish species
        
        Humans have taken water from..
        
        aquifers (underground water storage - effects the water table level
        
        lakes and rivers - surface water storage
        
        During the influence of the USSR - the Uzbekistan govt only considered the prospect of economic benefits from the mass production of cotton.
      - Location
        
        The Aral Sea is located in the continent of Asia, specifically in the central region of the Middle East. The Aral is situated and shared by two large countries - Kazakhstan and Uzbekistan - which has a semi-arid climate and hot and dry conditions.
      - Why is the Aral sea unlikely to recover?
        
        The Uzbekistan govt would require very large loans from external countries in order to reverse the effect, or restore the ecosystem.
        
        The money on loan from the world bank must be repaid, and Uzbekistan may not have the financial stability to do that - risky choice
        
        Irrigation has brought the water table to the surface of the land
        
        Drinking water & food crops are becoming polluted
        
        The semi-arid climate is hot and dry, any water that is open to sunlight will evaporate.
  - - - Since the aquifer can only be recharged by water percolating through the chalk surface, if the abstraction of water if greater then the recharge then deficit will progress - if its on a long term scale then the levels will continue to change and deficit.
    - - The underlying geology in the centre of the London basin causes issues in deficit of the aquifer. Below the surface lies impermeable clay, which prevents any water from infiltrating the ground and percolating into the pores in the rocks.
      - Urbanisation of the land also results in impermeable surfaces - concrete and infrastructure denies any chances that infiltration can occur - any green space in London like parks, wont allow infiltration due to the clay rock beneath the land.
    - - Over exploitation of London's aquifers in the 19th century caused drastic fall in the water table beneath London
      - Decline in industrial involvement around London by the 1990's mean the water table began to rise again with the allowance to recharge, at approximately 3m a year. However, this caused water to seep into foundations of buildings and underground train tracks. Possibility of infrastructural damage
      - The Thames water Company has been permitted to abstract water from the aquifer consistently in order to maintain the water table at a level which doesn't negatively effect the urban environment.
  - - - Nebraska - Colorado - New Mexico - Wyoming - Kansas - Texas - Oklahoma - S.Dakota
    - - Every summer the U.S. Central Plains go dry, leading farmers to tap into groundwater to irrigate sorghum, soy, cotton, wheat and corn and maintain large herds of cattle and hogs. As the heat rises, anxious irrigators gather to discuss whether and how they should adopt more stringent conservation measures.
      - They know that if they do not conserve, the Ogallala Aquifer, the source of their prosperity, will go dry. The Ogallala, also known as the High Plains Aquifer, is one of the largest underground freshwater sources in the world.
    - - There isn't a lot of precipitation in the area over the Ogallala Aquifer - less infiltration and less percolation - therefore, during hotter seasonal and occurrences of hydrological droughts, the irrigation farmers are dependent on the aquifer to sustain their vast irrigated farms. The strain they put onto the aquifer as they continue to abstract enormous volumes of water from the underground store - just adds to the deficit of the aquifer in the future, whereby the aquifer cannot retain its stored water any longer as it has been dissipated by the farmers.
      - Kansas - 39,000 pumps taking thousands of litres with no recognition of the effects on the aquifer.
      - 40% of Ogallala aquifer will be unable to support irrigated crop production in the next 80 years
    - - Farmers will obtain compulsory limitations on the volume of water that is allowed to be pumped out of the aquifer
      - Predicted - 6000 years for the aquifer to refill
      - Parts of the aquifer are predicted to dry up in the next 20 years due to over-abstraction
        
        Similar to the Aral sea - abstraction > recharge and little consideration for future consequences
    - - The 'Great Plains' and the Ogallala aquifer consists of san, gravel, clay and silt - with a maximum thickness of 800 ft
      - Clay - most porous but least permeable
      - Sand and gravel - porous and permeable
- - - - Drainage basins operate as an open system which can experience temporal changes by different factors like climatic changes or human changes
      - Water flows differentiate
  - - - high latitude may have more distinctive changes leading to diurnal and seasonal changes
      - low latitude (between the tropics) may receive little variation in rainfall across a year
      - 90 degrees - 0 degrees - -90 degrees
    - - high altitudes may have more distinctive changes leading to diurnal and seasonal changes
        
        e.g. the Himalayas
      - Increases in altitude lead to lower temperatures & lower altitudes implement higher temperatures
    - - low latitudes - greater angle of insulation - greater photosynthesis
      - mid latitudes - lower angle of insulation - lower rate of photosynthesis - low productivity
    - - size of catchment
      - medium - Rhone (France)
      - small - otter/exe
      - Large - amazon & the Mississippi
      - Network - all the same streams/river channels make up a drainage basins network
    - - Taking into account the transferring water between gas, liquid and solid
    - - Model Drainage basin
  - - - E.G. - ice ablation and accumulation
    - - E.G. - photosynthesis & respiration
    - - E.G. - Global warming
    - - E.G. - glaciers and interglacials
    - - E.G. - 'Snowball earth'
- - - - unsettled water
      - pulls air across masses from N. Atlantic - cold and wet
      - dry winds = pulling air and water across land
  - - - El Nino
        
        An El Niño occurs when the sea temperatures are 0.5oC above average
        
        This leads to warmer than average weather in the eastern Pacific
        
        The peak is usually in December
        
        The occur every 2-7 years
        
        The temperature of the ocean off the coast of Peru rises an average of 6-8oC causing thermal expansion and sea level rise
        
        Water off the coast of Australia and Indonesia is cooler and precipitation is reduced leading to droughts in Australia
      - Causes of El Nino
        
        In a non El Niño year there is descending air over the eastern Pacific and rising warm moist air over the western Pacific
        In an El Niño year the trade winds are reduced or reverse (going west to east) leading to a reversal of the conditions and rising air over the eastern Pacific and descending air over the western Pacific
    - - La Nina
        
        La Niña occurs when sea temperatures fall below average
        
        This brings cooler and drier than average weather in the eastern Pacific
        
        La Niña occurs every 3-5 years
      - causes
        
        Stronger than usual eastward trade winds and ocean currents
        These bring cold water to the surface through upwelling
  - - - Intense conditions (harsher then normal) - colder and wetter winters in temporal climates
      - Intense conditions of warmer air which holds the water - due to interference in the atmosphere
    - - thermohaline circulation - describes the movement of ocean currents due to differences in temperature and salinity in different regions of water.
      - water warms every 10,000 years
      - deep currents - colder + shallow currents - warmer
  - - - From the north west - polar maritime cold and wet front
      - From the south west - tropical maritime warm and wet front
      - From the north - arctic very cold and wet front
      - From the north east - polar continental cold and dry front
      - From the south east - tropical continental warm and dry front
    - - Orographic rainfall - unstable air is forced up & into the relief bar. Cold air over the relief bar will fall and be ineffective. Not collide
      - High surface tension connects droplets - larger droplets fall through the feeder clouds and into the seeder clouds - droplets coalesce and merge into the bigger drops, then they fall.
      - Leeward side provokes a rain shadow
      - Foehn effect - change from wet & cold conditions on one side of the mountain, to warmer and drier conditions on the other side (leeward side)
      - Turbulence over the mountain transports heat into and out of the moisture and produces the Foehn effect
      - warm air descends, can hold more water vapour and moisture is contained so clouds are not formed and keeps the warm and dry conditions which results in a rain shadow
  - - - clay particles swell in size when hydrated so pore spaces decrease in size
      - Sandy soils experience very little decline in infiltration capacity so produce very little overland flow
      - Infiltration rates can also differentiate depending on the land use (human geography input) for example - trampling by livestock on agricultural land compacts the soil into an impermeable layer at the surface of the ground. therefore the rate of infiltration will decrease as water takes longer to be absorbed into the soil, and causes overland flow. In the event of a stochastic storm, an impermeable ground would consequence is high levels of overland flow as the water struggles to infiltrate quick enough
      - splash erosion will lead to decreasing infiltration rates
  - - - Factors leading to variations in interception storage
        
        spatial scale- vegetation and land use vary & within different drainage basins and climates
        
        High latitudes - sloped branches provoke snow to fall off the tress during the winter seasons
        
        Drip ties encourage rainfall flow through the canopy
        
        The TRF prevents 80% of the rainfall in tropical rainforest regions and is stored in the canopy - meaning water can be scarce on the forest floor or little is found by the animals
        
        Temporal sale - difference in interception rates
        
        seasonal
        
        winter/summer - monsoon or winter
        
        diurnal / stochastic
        
        long term
    - - Temporal scale - different grows rates
      - High latitude biomes - limiting factors - low productivity
        
        temperate forests
      - TRF - optimum limiting factors, light, heat, CO2, water - low latitude (23 degrees north / -23 degrees south) consequences in mass encouragement of vegetation growth
        
        E.G. Amazon Rainforest - Brazil - South America 3.4653° S, 62.2159° W
        
        E.G. Congo Rainforest - Congo and DRC - (central) Africa 5.9175° S, 12.5484° E
        
        E.G. Okavango Delta - Botswana - Africa 19.6510° S, 22.9059° E
    - - Lake storage of runoff regulates stream outflow by sustaining low flows and supressing peak discharge
      - Factors leading to variations in surface storage
        
        input and output rates
        
        precipitation changes due to temperature changes
        
        storm events can increase lake level due to the excess rainfall and run off which is subsequently stored on the surface or infiltrated into groundwater storage
        
        stochastic storm events or droughts (hydrological droughts)
    - - Factors leading to variations in channel stroage
        
        Cooler temperatures - high latitude & altitude
        
        permeability of the land / geology - ground type - clay or sandy...
        
        seasonality - monsoon season will increase channel storage
    - - Factors leading to variations in soil moisture storage
        
        water movement - evaporation - root osmosis - vegetation differentiate
        
        type of soil - sandy soil has a higher field capacity due to the pore being able to absorb a lot of water via infiltration - leads to saturation levels increasing - water occupying pore spaces in the soil held by its high surface tension.
        
        type of ecosystem - TRF only receives 20% of precipitation as the canopy prevents 80% of rainfall from the ground surface
        
        human activity - deforestation of forests - ploughing in agricultural land - surface runoff
    - - Cannot soak in quick enough so moves across the surface
      - The soil is not saturated, but the water can not infiltrate (either because it is impermeable or the rainfall is too intense). It therefore flows over the surface as overland flow
      - Dry climate
    - - Wet climate
      - Pores in soil are full, so water cannot infiltrate and has to move on the grounds surface
      - the soil is full up of water - at maximum capacity - (saturated) so can not take any more so water flows over the surface as overland flow
    - - Soil moisture deficiency
      - Soil moisture utilisation
      - Soil moisture surplus
      - Soil moisture recharge
      - Long term changes - glacial periods - as temperatures gradually increase ice and snow on land is melting faster and in larger quantities. Therefore surface runoff into water basins is greater than usual, so soil moisture is higher
    - - Seasonal
        
        Low latitude
        
        Around the equator - low temperature range 3 degrees all year - high river output all year - perennial river
        
        Mid latitude
        
        winter at ML less sunlight - less leaves and so there's far less photosynthesis and transpiration - ML has deciduous forests and change due to seasonalilty
      - Altitude
        
        In alpine climates - no growth in winter - covered in snow for example the Alps - France
        
        Reduction of river levels - until the spring melt - is effected by cryosphere storage and temperautre
      - Diurnal
        
        Increased evapotranspiration during a day - decreases at night
        
        More heat and light in daytime - carries out greater levels of photosynthesis
      - Decadal / Long term
        
        warmer wetter winters - increasing river output (channel flow increase) - increasing winter precipitation (channel flow levels increase)
    - - Excess overland flow
- - - - effected by differentials in temperature of the land its above
      - JS south of the UK - wet & low pressure climatic conditions
      - JS north of the UK - warmer/drier & high pressure climatic conditions
  - - - The River Rhone flows a high level area in the valley of the Alps, in which its fed by glaciers during the seasonally occurring spring melt from more frequent higher temperatures, which causes high amounts of surface runoff in the Rhone drainage basin.
      - Winter months consists of settling snow and ice due to the lower temperatures in the alpine temperate climate. The water remains on the landscape during the colder seasons and settles as an addition to the cryosphere storage.
      - Response time differentiates as the topography of the landscape changes throughout the drainage basin.
      - The River Rhone's dense network of connecting tributaries in its drainage basin, which collectively feed into the main river and seasonally supply either a very large volume of water (spring and summer) or smaller volumes of water (winter).
    - - Located in eastern France, the Rive Saone is one of three rivers that acts as major tributaries which feed into the River Rhone. The Saone joins the Rhone from the north in the large French city Lyon, its the biggest tributary that feeds into the Rhone and supplies a large volume of water into the Rhone's main river channel. The addition of the Saone's drainage basin to the Rhone's has a substantial effect on the water levels in winter, while it passes through and out of Lyon.
      - The Saone drainage basin receives its largest input supply from precipitation during the winter months - December to February - which is seasonally different to the Rhone's main input during spring - March to May - as the river is based on a lower level altitude, therefore the temperatures are also not too low, so the alpine temperate climate has no effect in this area of freezing and precipitation falling as snow, therefore, the winter months bring steady rainfall into the drainage basin's network of tributaries which will have a faster response time as the drainage basin is saturated and the capacity for infiltration is high, as well as quick overland flow and efficient surface runoff.
      - Atlantic depressions (cool air mass) from the north bring frontal rainfall as the main input into the drainage basin of the Saone and Rhone rivers.
  - - - Brahamaputra River
        
        Brahmaputra is one of the largest rivers in the world and rank fifth with respect to its average discharge. The river originates from the Kailash ranges of Himalayas at an elevation of 5300 M.
        
        2,900km long
        
        The Brahmaputra is a trans-boundary river which flows through Tibet, Northeastern India, and Bangladesh.
      - Meghna River
        
        The Meghna River is one of the major rivers in Bangladesh, one of the three that form the Ganges Delta, the largest delta on earth, which fans out to the Bay of Bengal.
        
        Length - 264 km
        
        It rises in the Manipur Hills of northeast India as the Barak River and flows west becoming the Surma River and then flows south as the Meghna River, a total of 946 kilometres (588 mi) of which 669 kilometres (416 mi) are within Bangladesh, to the Bay of Benga
      - Ganges River
        
        Much of the Ganges has been diverted for irrigation purposes, this has removed amounts of silt and prevents the floodplains further downstream from continuous building. The artificial watering of crops is a very appealing concept for Bangladeshi resident as it would allow them to grow food for their family to sustain their health. (subsistence farming)
        
        The Ganges is a trans-boundary river of Asia which flows through India and Bangladesh. The 2,525 km river rises in the western Himalayas in the Indian state of Uttarakhand.
    - - 70% of the flood plain and delta is is >1m or slightly <1m
      - 10% of the land is made up of rivers and lakes
      - Snowmelt from the Himalayas takes pace in late spring and summer, provoking excessive runoff in the drainage basin through the tributaries which feed into the main river channel
      - Tropical storms and monsoon rains proceed to input water into the drainage basin causing excess run off and possible overland flow
      - If the 3 rivers peak at similar times with excessively high discharge, settlements are highly endanger of flooding as the embankments cannot withstand the volume of water flowing within the larger channels
    - - Urbanisation of the flood plains has increased magnitude & frequency of floods
      - Global warming has resulted in rising sea levels, in which causes major problems for Bangladesh as the entirety of some cities are bulit on land only 1 or 2 meters above sea level.
      - Deforestation in Nepal and the Himalayas increases run off and adds to deposition and flooding downstream which consequently flows through Bangladesh
      - The building of dams in India is a major causation for the problem of sedimentation in Bangladesh
      - Poorly maintained embankments (levees) leak and collapse while the rivers exceed average discharge.
      - Increasing population has pressured Bangladesh into rapidly building poor shelter and homes for people, has resulted in new wells being implemented, lowering the water table and the subsequent subsidence of land making it even more prone to flooding
    - - The Himalayas
        
        The Himalayas, or Himalayan mountain range, is a vast rocky arrangement of large scale mountains, separating the plains of the Indian subcontinent from the Tibetan Plateau.
        
        The mountain range is made up of 10-20 km-thick metamorphic rocks (schist and gneiss) and granites situated at altitudes of 3000 m to over 8000 m.
      - Low lying flood plains and the delta
        
        Dhaka's greater metropolitan area is home to 18 million residents. Many families live in the city's most flood-prone areas.
  - - - Many western states rely on the cool season to produce snow, which packs and settles and forms large masses onto mountain snow fields. This is so the natural reservoirs are replenished in order to sustain these states with natural blue water. Post-cool season brings spring melts as temperatures rise over 0 degrees and ablation occurs, leading to surface runoff and recharge in the drainage basin as the water infiltrates and percolates ONLY if the ground is not frozen.
      - Channel flow rates increase as do discharge levels in the basins network - tributaries
      - 2016/2017 cold season brought an abnormal and frighteningly huge amount of snowfall
    - - Location of the South Platte River Basin
        
        The South Platte River Basin is situated between three central US states - Wyoming, Nebraska and Colorado. Colorado (79 percent of the basin), Nebraska (15 percent of the basin), and Wyoming (6 percent of the basin).
        
        The total basin area covers approximately 62,900km2
        
        Seasonal snow totals in the 2016/2017 wet season
        
        Sugar Bowl - recorded 1.9m
        
        NorthStar - recorded 1.7m
        
        Soda Springs - recorded 1.7m
        
        Bear Valley - recorded 1.2m
  - - - Physical causes
        
        Unusually frequent or active depressions and fronts change the atmosphere
        
        Atmospheric convection
        
        Cyclonic winds by mountainous terrain intensified already excessive - precipitation
        
        610mm fell directly over Lake Wivenhoe
        
        40% more rainfall then normal across the 7 days
      - Human causes
        
        Dam was released - 90 cm from the top of the dam - almost reaching peak volume - too much pressure amounting up.
        
        A significantly huge volume of water was released into the Brisbane River.
      - Australia 2011 - case study
        
        Brisbane river & Queensland
        
        The Brisbane River’s catchment is some 13,570 km2 in area, bounded to the west by the Great Dividing Range and to the southeast and north by a number of smaller coastal ranges. Most of the catchment is rural—forestry and grazing land—but also includes the major metropolitan areas of Brisbane and Ipswich, as well as a number of smaller townships
        
        The Brisbane River is the longest river (309 km) in south east Queensland. Its source is located in the Brisbane Range some 120 km north west of the city of Brisbane. From there it makes its way south before meeting the Stanley River, just downstream of Somerset Dam, to run into Lake Wivenhoe, the main water supply for Brisbane. Lake Wivenhoe was created by the Wivenhoe Dam completed in 1984 in response to severe flooding in 1974 and with the principal aim of protecting Brisbane from future floods. Since its construction many considered that this dam would eliminate the flood risk to Brisbane, notwithstanding warnings against this way of thinking. Downstream from the Wivenhoe dam the river flows eastwards, meeting the Bremer River near Ipswich before making its way through Brisbane’s western suburbs towards the Pacific Ocean.
        
        Eastern Australia - 2011 - experienced severely high amounts of rainfall over 7 days, subsequently leading to flash floods, as the stochastic storm surges causes extreme excess runoff in the Brisbane drainage basin.
        
        extensive flooding had impacted 75 per cent of the state and a disaster zone was declared. In total, 33 people lost their lives, with three bodies never recovered and declared deceased by the State Coroner in June 2012. Evacuations numbers totaled 5 900 people from 3 600 homes.
      - Long-term climatic changes
        
        Climate change - wet conditions will lead to greater wet weather occurrence
        
        Less cloud cover - so much cooling/condensing/rainfall. They're being 'rained out', less water recharge in the drainage basin as the volume of water being inputted is getting larger but less frequent.
      - 80% of all rainfall into the tropics is recycled by evaporation and transpiration
  - - - Incoming solar radiation - heat energy is transferred into the ITCZ
      - Angle of insulation changes in correlation to the position of the ITCZ
    - - Seasonal reversal of wind - NE during winter (November-February) / SW during summer (may-October)
      - Shift in wind direction can either bring excessive rainfall and wet conditions or hot & dry deficit conditions
      - 2020 - June in India - excess rainfall - 110% above average rainfall during the monsoon season
      - The oceans remain a lower temperature than the land, the air above it retains at a high pressure
      - The difference in pressure causes the sea breezes to blow ocean to land - air rises to higher altitudes above the land
    - - Summer
        
        Warm wet - rainfall peaking in June
        
        Wind reverses - travels upwards - Air masses travelled over the Indian Ocean onto the land, it rises, causes storms and heavy rainfall
        
        ITCZ travels upwards - sub-tropical jet stream in the northern hemisphere, brings excess rainfall in the area as the jet stream has moved position
      - Winter
        
        Jet stream position moves south - dry season commences
        
        Dry air comes from the north, warms up over land (Asia) therefore it doesn't reach the saturation point and condense and cool
    - - Intertropical convergence zone
      - Differential heating - refers to the difference in how land and water surfaces absorb heat
      - Extreme heating and cooling of large land masses (Asia) in relation to the nearby Indian ocean
      - The effect of the Himalayan mountain range on air masses (causes uplift) in this particular location
      - Northwards movement of the ITCZ during June - warm wet air from the Indian Ocean
      - The air circulates back towards the equator in the lower atmosphere creating the trade winds.
      - Air descends at 30 degrees N and 30 degrees S - creating an area of high pressure with dry air
- - - - Rising and falling limb of the line graph
      - lag time - time difference between peak discharge and peak rainfall
      - Peak rainfall input - represented in a bar chart along the x-axis
      - storm flow - water in the river as a response to the stochastic event
        
        results in excess surface runoff and possible overland flow - hortonian overland flow or saturation excess flow
    - - climatic
        
        Rainfall intensity
        
        Precipitation type
        
        Antecedent conditions
        
        antecedent stream is a stream that maintains its original course and pattern despite the changes in underlying rock topography. A stream with a dendritic drainage pattern, for example, can be subject to slow tectonic uplift.
        
        seasonal evapotranspiration rates changing
      - non-climatic
        
        land use - land use zoning
        
        agriculture
        
        afforestation or deforestation
        
        urbanisation - impermeable surfaces like concrete, prevent infiltration rates causing higher rates of surface runoff
        
        geology and permeability
        
        Size of drainage basin
        
        Drainage density
        
        length of all tributaries divided by the area
        
        Drainage basin response time - can be dependent for controlling the overland flow or surface runoff levels
  - - - 100-200mm of rain normally falls across al of August . The 16th of August - 200mm fell in one afternoon
      - Intense conditions of extreme precipitation over a short time period was the causation of flash floods
    - - Many building were damaged - Boscastle Museum had infrastructural damage. 5 collapsed buildings. 84 cars were washed into the harbour.
      - 360,000 extra visits in 2006 post-flood
    - - Narrow valleys - the flow of water is restricted and was funnelled down the slopes of the drainage basin
      - Small areas of woodland - only little water is intercepted and absorbed by vegetation. Vegetation ineffectively prevented or slowed the water flows
      - Steep slopes - overland flow enters the tributaries very quickly - resulting in fast flowing, uncontrollable water movement
      - Very short lag time due to the upland areas being dangerously close to the village settlements
    - - Climatic factors
        
        Crossing Cornwall's land is air masses of different temperatures. Northern Cornwall faces the Atlantic cold front bringing colder conditions - whereas the southern side of Cornwall was experiencing warmer conditions which heated up the land. The cold front met the hot land and hot air above it, and began to cause a convergence zone over the drainage basin of Boscastle, The problematic mixture of these air masses caused significantly high uplift, which lead to rapid cooling and condensing, which resulted in unexpectedly high and rapid precipitation over the northern coast of Cornwall - but significantly affected the drainage basin of Boscastle.
        
        Cumulonimbus clouds
  - - - Intermittent - seasonal flows due to the differentials in precipitation and storages
      - Ephemeral - flows in correlation to a stochastic event like a storm, like a response
      - Perennial - constant flow all year
    - - Temporal
        
        seasonal variations in the pattern of discharge within a year / precipitation varies
        
        short term variations due to climate change within a decade due to fluctuations in temperature/precipitation e.g. droughts, excess and changes in land use
        
        Long term variations die to climate change / and or changes in land use
      - Spatial
        
        variations occur within and between drainage basins due to climatic factors - linked to latitude and altitude - drainage basin characteristics including land use
  - - - e.g. 2007 River Severn
    - - e.g. Somerset levels
  - - - Increase in urbanisation progression - urban sprawl across the green belt - necessary for more drains and gutter systems - if not then in the event of a stochastic storm, the flash flooding would cause greater damage, water will move faster and more direct down the drainage basin - greater overland flow and excess runoff
    - - Channelisation - water is moving more direct in a drainage basin and moves faster
      - response time changes - impermeable surfaces are a significant causation for excess runoff in a drainage basin - urbanisation consequently results in greater flood damage
    - - reduces vegetation, exposing soil and bare ground - leads to greater overland flow as the field capacity is reached - splash erosion - impermeable surfaces like concrete prevent any infiltration and percolation so underground water storage may also decrease
    - - Green and brown field sites
        
        Building on green field sites is a consequence established by urban sprawl onto the surrounding green belt or fields - there's basically no positives
      - Deforestation and afforestation
        
        Deforestation results in less interception and soil erosion - increases surface runoff and overland flow if hortonian overland flow or saturation excess flow is reached - dependence on field capacity too