Geography GCSE - OCR

- the sea.
- the land.
- the atmosphere.

What different parts make up the hydrological system ?

There are no outputs or inputs the water just flows round and round the cycle.

What is meant by a closed system ?

When water is heated by the sun and turns into water vapour.

What is evaporation ?

Evaporation of water from plants.

What is transpiration ?

Evaporation from both a water and from plants.

What is evapotranspiration ?

When water soaks into the soil.

What is infiltration ?

When water moves vertically through soil and rock.

What is percolation ?

When water in the soil flows downhill.

What is throughflow ?

When water in rock flows downhill.

What is groundwater flow ?

When water flows on top of the ground.

What is surface runoff ?

The flow of water in a river.

What is channel flow ?

It's when water is held in a river.

What is channel storage ?

When water is stored underground in soil and rocks.

What is groundwater storage ?

A rock that stores water.

What is an aquifer ?

When water lands on thing such as plant leaves and doesn't land in the ground.

What is interception storage ?

When water is held in thing such as lakes and reservoirs.

What is surface storage ?

Part of the hydrological cycle that happens on land.

What is a drainage basin ?

- tributary(small river).
- source (upland).
- confluence (where two rivers meet).
- mouth (where river flows into the sea or into a lake).

What are the key features of a drainage basin ?

- mechanical.
- chemical.
- biological.

What are the three types of weathering ?

When water gets in cracks in rocks and freezes to break up the rocks.

What is mechanical weathering ?

The breakdown of rock by changing its chemical composition.

What is chemical weathering ?

Breakdown of rocks by living things e.g. Tree roots growing into cracks.

What is biological weathering ?

Steep gradient, v shaped valley narrow and shallow channel.

What is the upper course of a river like ?

Medium gradient, gently sloping sides, wide deeper channel.

What is the middle course of a river like ?

Gentle gradient, very wide almost flat valley, very wide and very deep channel.

What is the lower course of a river like ?

- hydraulic action.
- corrosion.
- attrition.
- corrasion.

What are the four processes of erosion ?

The forces of the water breaks rock particles away from the river channel.

What is hydraulic action ?

Eroded rocks picked up by the river scrape and rub against the channel wearing it away.

What is corrasion ?

Eroded rocks picked up by the river smash into each other and break into smaller fragments rounded off as they rub together.

What is attrition ?

River water dissolved some types of rock such as limestone.

What is corrosion ?

Large boulder shaped particles are pushed along the river bed by the force of the water.

What is traction ?

When pebble-sized particles are bounced along the river bed by the force of water.

What is saltation ?

Small particles like silt or clay are carried along by the water.

What is suspension ?

Soluble materials dissolve in the water and are carried along.

What is a solution ?

Mr grove smashing his head off of a skogafoss door

What is attrition ?

It's when the river drops eroded material it happens when a river loses velocity.

What is deposition ?

- the volume of water decreases.
- amount of eroded material increases.
- water is shallow (inside of a bend).
- the river reaches its mouth.

Why would a river lose velocity ?

In the upper course.

Where are waterfalls and gorges found ?

Soft rock is eroded more than hard rock which creates a step in the river, soft rock is eroded more which creates a steep drop.

How are waterfalls formed ?

Hard rock is undercut by erosion, becomes unsupported and collapses. The collapsed rock eroded soft rock at the base of the waterfall and creates a deep plunge pool. The rick gets undercut more times and the waterfall retreats.

How do waterfalls begin to retreat ?

Large bends in the river.

What are meanders ?

- Inside bend, slip off slope, slower current and deposition.
- outside bend, river cliff, faster current and erosion.

What are features of a meander ?

Erosion on the outside bends of a meander get closer together forming the neck. Usually during a flood the neck is broken. Deposition eventually cuts off the meander forming an ox-bow lake.

What is an ox-bow lake ?

Flat areas of land that flood.

What are flood plains ?

Natural embankments caused by deposition from rivers flooding on the flood plains.

What are levees ?

Low lying areas where a river meets the sea or a lake.

What are deltas ?

Lol

River Tees

They highest amount of river discharge.

What is peak discharge ?

The volume of water that flows in a river per second - cumecs.

What is river discharge ?

The delay between peak rainfall and peak discharge.

What is lag time ?

The increase in river discharge as rainwater flows in to a river.

What is rising limb ?

The decrease in river discharge as the river returns to normal.

What is falling limb ?

-High / intense rainfall
- impermeable rocks.
- saturated (wet) soil.
- steep slopes -> fast runoff.
- less vegetation -> less interception.

What are some factors that make discharge steeper on a hydrograph ?

- Low / light rainfall.
- permeable rocks.
- dry soil.
- gentle slopes -> slow down runoff.
- more vegetation -> more interception.

What are some factors that make discharge less steep on a hydrograph ?

- Deforestation means less interception.
- urbanisation means more impermeable materials.
- straightening rivers.

What are some ways humans contribute to flooding ?

- death.
- spread of disease.
- loss of jobs.
- loss of houses.

Some impacts of flooding are ?

Hard and soft.

What are the two types of engineering ?

- dams and reservoirs
- straight channels.
- man made levees.

What are some examples of soft engineering that can reduces the risk of flooding / its effects ?

- store water and release it slowly.
- drinkable.
- hydroelectric power
- attractive.
- very expensive
- flood settlements.
- less fertile farmland downstream.

What are some advantages and some disadvantages of dams and reservoirs ?

- water travels out of the area faster.
- it floods areas downstream instead.

What are some advantages and disadvantages of having straight channels ?

- river can hold more water.
- quite cheap.
- if they fail it causes catastrophic flooding.

What are some advantages and disadvantages of man made levees ?

- flood warnings.
- preparation.
- flood plain zoning.

What are some examples of hard engineering that reduce the risk of flooding / its effects ?

- impact is reduced, people have time to move possessions or evacuate.
- doesn't stop the flood, people may not get the warning.

What are some advantages and disadvantages of flood warnings ?

- impacts of flooding are reduced.
- doesn't guarantee safety, false hope ?
- expensive to modify homes.

What are some advantages and disadvantages of preparation ?

- risk of flooding is reduced.
- there aren't houses to be damaged.
- limits urban expansion.
- doesn't help if area has already been built on.

What are some advantages and disadvantages of flood plain zoning ?

Lol

Boscastle (MEDC)

Lol

Bangladesh (LEDC)

- hydraulic action.
- corrasion.
- attrition.
- corrosion.

What are the four processes that wear away coasts due to waves ?

Waves that carry out erosional processes.

What are destructive waves ?

- high frequency.
- high and steep.
- backwash more powerful that swash.
- material moved from the coast.

What are some properties of destructive waves ?

- Wind (strong wind -> powerful waves.
- fetch (big fetch -> powerful waves.

What factors effect the size and power of a destructive wave ?

- retreating cliffs.
- headlands.
- bays.
- caves.
- arches.
- stumps.
- stacks.
- coves.

What coastal land forms are produced from erosion ?

Waves erode a wave cut notch in the cliff side, enlarged over time. The rock becomes unstable and the material falls. The material is washed away by the waves. Another wave cut notch is formed and this repeats.

How do coastal cliffs retreat ?

Occur where there is alternating bands of resistant and less resistant rock, the less resistant rock is eroded which forms a bay, where the rock is more resistant a headland is formed.

How are headlands and bays formed ?

Headland have small cracks in, water gets inside the cracks and eroded until eventually a cave is formed.

How are caves formed ?

The water continues to erode inside of the rock until it breaks out the other side of the headland.

How are arches formed ?

Water erodes the rock that supports the arch and it collapses so the rock is isolated.

How are stacks formed ?

The stack continues to be worn away until it's a small stump which can sometimes be covered at high tide.

How are stumps are formed ?

A wide circular bay with a narrow entrance.

What is a cove ?

They form where there is a band of hard rock with soft rock behind it. Cracks in the hard rock are eroded by waves, the soft rock behind is easily eroded to form the cove.

How are coves formed ?

When materials are carried along the coast in a zig-zag motion in the direction of the prevailing winds.

What is longshore drift ?

Waves that deposit more material than they erode.

What are constructive waves ?

- Low frequency.
- swash is powerful.
- backwash is weak.
- made by weak wind.
- have a short fetch.

What are some properties of constructive waves ?

- flat and wide.
- sand is small.
- long gentle slope.

What are the characteristics of a sand beach ?

- steep and narrow.
- sand is large.
- steep slope.

What are the characteristics of a shingle beach ?

Beaches that form at sharp bends in the coastline, sand and shingle is deposited in the sea due to longshore drift, strong winds curve the end and the sheltered area can become mud flat or even salt marsh.

What are spits ?

When a spit extends really far and joins two headlands together the water behind the bar is a lagoon.

What is a bar ?

Lol

Broadhaven

- loss of tourism.
- business premises could be destroyed.
- salt reduces fertility of soil.
- property prices fall.
- insurance prices rise.

What are some economic reasons for wanting to protect the coastline ?

- deaths.
- polluted water.
- loss of housing.
- loss of jobs.
- damage to roads.

What are some social reasons for wanting to protect the coastline ?

- salt could kill organism in the ecosystem.
- trees / plants could be uprooted / drown.
- sites of special scientific interest could be destroyed.

What are some environmental reasons for wanting to protect the coastline ?

- sea wall.
- rip rap.
- groynes.
- revetments.
- gabions.
- breakwaters.

Examples of hard engineering in the coast ?

- prevents erosion.
- prevents flooding.
- creates strong backwash.
- expensive to build and maintain.

What are some advantages and disadvantages of sea walls ?

- absorb wave energy.
- reduce erosion.
- reduce flooding.
- can be moved by string waves.

What are some advantages and disadvantages of rip rap ?

- greater protection from flooding.
- greater protection from erosion.
- starve beaches along the coast.
- those narrow beaches don't protect the land from erosion.

What are some advantages and disadvantages of groynes ?

- absorb wave energy.
- reduce erosion.
- expensive.
- create a strong backwash.

What are some advantages and disadvantages of revetments ?

- absorb wave energy.
- reduce erosion.
- look ugly.

What are some advantages and disadvantages of gabions ?

- reduced the waves erosive power.
- expensive.
- damaged by storms.

What are some advantages and disadvantages of breakwaters ?

- beach replenishment.
- managed retreat.

Examples of soft engineering in the coast ?

- wider beaches that slow the waves.
- protection from floods and erosion.
- taking material from seabed can kill some organisms.
- expensive.
- has to be repeated.

What are some advantages and disadvantages of beach replenishment ?