water cycle key info Flashcards
what are stores, fluxes and processes and what are examples of each
STORES - stocks of water, where water is held
eg oceans, lakes, rivers, glaciers
FLUXES- measurements of the rate of flow between stores
eg precip rate, evapotrasp rate, run off rate
PROCESSES- physical factors that drive the fluxes
eg precip, run off
what are the different ‘spheres’
atmosphere- gasses surrounding earth
cryosphere- water in solid form
biosphere- water in ecosystems
pedosphere- in soil
hydrosphere- total water on earth
lithosphere- crust and upper mantle
what are the three types of rainfall and how do they work
relief/ orographic rainfall - moist warm air forced to rise over hightened land
- condenses and cools as it is pushed up
- causes rain on windward side and no precip on leeward side causing a rain shadow
convectional rain - sun heats grounds warm air rises
- cools and condenses and forms clouds
frontal rain- warm and cold air front meet
- warm air forced to rise
- cools and condenses forming cloud
what are the different global air circuation cells in order
polar, Ferrell, Hadley
what is an inter tropical convergence zone
area commonly associated with tropical rainforest climate
high rates of evapotranspiration and convectional rain
moves during year and leads to wet and dry season
what is the thermohaline circulation system
- water in polar is colder and denser so sinks
- cold sinking water draws warmer water in from surface
- draws water across surface from tropics
- movement of water from tropics draws cold water up to be warmed
what is a drainage basin
an area of land drained by a main river and its tributaries
what is the source, tributary, watershed , mouth, confluence and catchment of a river basin
source- where river begins
tributary- smaller river flowing into larger
watershed- highland that separates waters flowing to different rivers
mouth- end
confluence- meeting point of 2 or more rivers
catchment- area of land drained by river
what are the physical factors affecting drainage basins
precipitation
interception - dependent on veg
percolation and groundwater flow- rate depends on permeability of the rock
runoff- common where ground is impermeable
evapotransp
channel flow
what are human factors affecting drainage basins
- groundwater abstraction
- dam construction (incr surface water ice evaporation)
- urbanisation
- cloud seeding
what is a water budget
annual balance of inputs and outputs
can see when there is enough water or not enough
what is a river regime
variation in flow of a river during the year
what is a river regime based on
- drainage basin area
- variation in altitude
- geology
- precipitation
- land use
what is a storm hydrograph and what are the key factors that it includes
shows variation in discharge within a short period of time
- peak rainfall
- peak discharge
- lag time
- rising limb
- falling limb
what are factors that affect the shape of a storm hydrograph
- duration and intensity of precipitation
- size of drainage basin
- number of tributaries
- natural vegetation
- rock type
- slope gradient
- urbanisation
what is drought
extended period of deficient rainfall compared to previous years average for a region
what are the four types of drought and what are the characteristics of each
METEOROLOGICAL
- long term precipitation lower than normal
- supply of irrigation water declines
AGRICULTURAL
- not enough soil moisture for crops
- fall in groundwater
- poor cropyeilds
- gov aid needed
HYDROLOGICAL
- lake river ground water is deficient
- little soil moisture
- less water for urban supply
FAMINE
- widespread failure of agriculture systems
- food shortages
- rural economy collapses
- International aid required
what are the human causes of drought
- dam construction
- deforestation
- over abstraction of aquifers
- sewage and waste contamination
- excessive irrigation
- climate change
what are wetlands and why are they important
- areas where water covers soil
- cover 10% of land surfaces
- acts water stores
- removes pollutants and traps and recycles nutrients
- diverse food chains
- tourism opportunities
what is droughts impact on wetlands
- interception decreases
- progressive loss of habitat
- reduced ability to store flood water
- soil moisture reduced
- soils may oxidise and release carbon
- may eliminate species
why are forests important
responsible for much interception
cause infiltration and overland flow
what are droughts impacts on forests
- increased tree mortality
- impacts on habitats and food chain
- incr susceptibility to disease
- some trees rely on others
- dries soil out
- incr forest fires
what is flash flooding
a flood caused by very intensive rainfall
what are the human causes of flooding
- urbanisation
- deforestation
- mismanagement of rivers/ channelisation
- intensive farming
