Hydrosphere Flashcards
evaporation
the process of solar energy turning liquid into vapor or gas
advection
the horizontal transport of liquid and air
condensation
the process of vapor or gas turning into a liquid
precipitation
any moisture which falls from the atmosphere to the ground
snow, sleet, hail etc.
surface run off
movement of water across the surface of the ground
imprmeable surface
infiltration
the movement of water into soil due to gravity
permeable surface
through flow
water travelling through the soil due to gravity
percolation
deeper movement of water through permeable rock pores by gravity and capillary forces
groundwater flow
deeper movement of water through rocks
transpiration
the evaporation of water from plants through leaf pores
evapotranspiration
water loss through evaporation and transpiration
sublimation
conversion of solid to gas witnessed on ice and glaciers
abrasion
river erosion
when small particles of rock carried by the river rub the surface of the river bed and wear it away
hydraulic action
river erosion
water flowing past river banks is forced into tiny cracks, compressing air causing materials to be dislodged
attrition
river erosion
when the load repeatedly hits against each other causing it to break apart
corrosion
river erosion
when the river water disolves minerals from the rocks and washes them away
traction
river transportation
when larger particles such as pebbles are rolled along the river bed
saltation
river transportation
when sand-sized particles bounce along the river bed
suspension
river transportation
fine particles such as silt are carried within the water
solution
river transportation
when materials disolve into the water and are then carried away by the river
upper course
river course
characteristics
- narrow v-shaped valley
- steep gradient
- vertical erosion
- large, rough, angular load
features
- waterfalls
- rapids
- gorges
middle course
river course
characteristics
- more open v-shaped valley
- gental gradient
- vertical and lateral erosion
- small, smooth load
features
- meanders
- river cliffs
- river beaches
lower course
river course
characteristics
- flat land (flood plain)
- wide channel
- fast flowing
- lateral erosion
- very small, smoothe, rounded load
features
- meanders
- ox-bow lakes
- levees
- braiding
- deltas
v-shaped valley
formation
- vertical erosion by river - the river cuts a deep slice into the landscape through hydraulic action, abrasion, and corrosion
- as the river cuts down, the valley sides become exposed to weathering which loosens the rock and gravity causes peices to fall into the river
- fallen debris aids further abrasion leading to more erosion
- as the river moves downstream it carries the debris and the channel becomes wider and deeper, creating a v-shaped valley between interlocking spurs
waterfall
formation
- the river flows over bands of hard and soft rock, the soft rock erodes more quickly than the hard rock - differential erosion
- the river erodes by three processes: hydraulic action, abrasion, corrosion
- the river undercuts the hard rock, creating an unsupported overhang which eventually collapses into the plunge pool due to gravity
- fallen matierals aid further erosion deepening the plunge pool
- over a long period of time the waterfall retreats upstream creating a gorge
meanders
formation
- straight river channels have pools and ripple
- pools are deep with greater erosion
- riffles are shallow areas formed by deposition of course sediment on the river bed
- these pools and riffles cause the river to flow from side to side
- faster moving water on the outside bend has more energy leading to more erosion through abrasion and hydraulic action, creating a river cliff
- slower flowing water on the inside of the bend has less energy leading to deposition - the river load is dropped to form a river beach
- this process is aided by helicoidal flow which is a corcscrew action which moves material from a river cliff to a river beach
- over time, repeated erosion and deposition makes the meander more extreme
ox-bow lake
formation
- explain formation of meander
- faster flowing water on the outside bend erodes by hydraulic action and abrasion
- slower flowing water on the inside bend deposits the river load
- continual erosion and deposition narrows the meander neck
- during a flood the riiver will flow across the neck creating a straight channel
- deposition on the edge of the straight channel slowly cuts the meander off from the river
- eventually the meander is completely isolated forming a horse-shoe-shaped lake called an ox-bow lake
factors which influence the shape of a hydrograph
- area, shape, slope of drainage basin
- type of rock/geology - permeability
- soil type - infiltration rate
- land use - urban, rural
- vegetation - interception
- drainage density - tributaries
- storage capacity (of river channel)
