Geography diagrams For paper 1

• At the equator the sun warms the earth,which transfers heat to the air above causing it to rise. this cause a low pressure system with rising air, clouds and rain.
• The air cools and moves to 30 north/south 
• 30 north and south of the equator the aire sinks. This creates a high presure system with cloudless skies and very low rainfall.
• The cool air reaches the cloudes and oves as surfacewinds either goes back to the equator or the poles. Surface winds=Trade winds
• At the equator these trade winds meet and are heated by the sun.This cause to rise and form clouds
• THERE ARE THREE TYPES OF CELLS:HADLEY,FERREL AND POLLAR

HIGH PRESSURE=AIR SINKS

LOW PRESSURE=AIR RISING

• tropical storms develope at sea temperatures is 27 degrees celcius.
• warm moist air rises= area of low pressure > this release huge amounts of energy >this make storms more powerful.
• tropical storms move towards the east
• the corriolos effect cause the storm to spin
• The storm get stronger due to the energy from the warm water so wind speed increases
• They lose strength when they move over land or cooler water.
• Tropical storms occur at 5 and 30 north and southof the equator.

• water enters the crack in the rock
• overnight the temperature drops and the water freezes and exapnds causing the crack to widen
• During the day the water melts and goes deeper into the cracks
• the process is repeated until the rock splits.

• Plant roots can get into small rocks
• As the root grows the cracks get bigger
• This causes smalle pieces of rock to break off

• Bits of rock fall off the cliff face, usually due to freeze-thaw weathering.

• Large blocks of rock slide downhill.

• Saturated soil slumps down a curved surface.

• Wave cut platform caus the most erosion at the foot of the cliff.The erosion that takes place is many hydraulic errosion and abrasion.
• This creates a wave-cut platform which is enlarged as erosion occures.
• The rock above the notch becomes unstable and eventually collapses.
• The collapsed material is washed away.
• the repeated collaping mena that cliff retreats.
• A wave cut platform is what is left behind.

• There are vertical bands of soft rock and hard rock.
• The soft rock has a low resistance to erosion so it easily erodes and this forms a bay.
• the hard rock has a high resistance to erosion so it erodes much slower than the hard rock and it is left jutting out forming a head land.

• Headlands are usally the made of resistant rock.
• Waves crash into the headlands and enlarge the cracks
• Repeated erosion and enlargement of crakcs cause a cave to form.
• Continued erosion deepens the cave until it breaks throught the head land which then forms an arch 
• Erosion continues to wear away the rock supporting the arch.
• the roof the arch then collapeses.
• This then forms a stack that is seperate from the headland.

• Sediments carried by longshore drift
• Longshoredrift transports sand and single past the bemd and deposited it in the sea.
• the strong wind and waves can curve the end of the spit
• The sheltered area behind the spit is protected from waves.
• Overtime the sheltered are can become a marsh or mudflat.

When the spit meets another headland a bar is formed. The bar cuts off the bay between the headland from the sea so a lagoon is formed from behind the bar.

Waterfalls are founds in the upper course of a river.

• waterfall form where a river flows over an area of hard rock followed by a soft rock.
• the softer rock is eroded by hydraulic action and abrasion maore than the hard rock
• The hard rock is eventually undercut by erosion. It becomes unsupported and collapses.
• The collapsed rock are swirled around at the foot of the waterfall.This creates a plunge pool.
• Overtime more undercutting causes more collapses.The waterfall will retreat leaving behind a steepsided gorge.

Meanders are found on the middle course of a river.when river flow over flatter surface they develope large bends called meanders

• ther river flows fastes in the outside.this cause increased speed and increase erosion. which forms a river cliff
• Water in the inside flows much slower causing the water to deposti material in the river this then creating a gentle slope of sand and shingle called a river beach.
• This repeated erosion and deposition mean that the meander becomes more bendy.

• the shape of a meander will change over time
• erosion narrows the neck of the land within a meander and the meander move closer to each other 
• When there is a very high discharge the river cuts the neck.taking a new straighter path
• Depostion will occur and cut off the original meander leaving a oxbow lake.

They occur in the lower course of a river when there is an increase in water flow snd flooding occurs.

• Sediments that have beed eroded up stream have been transported downstream
• when river floods the sediments spread across the floodplain.
• when a flood happens the river looses energy and the hevier material is deposited first  on the side of the river banks
• and smaller material futher away from the river bank
• After many flood the sediments build up and increase the hieght of the river bank.so the river can carry more water and dercreases the chances of flooding.

It is an area of land which i covered in water when the river is flooded.

• they occur due to both erosion and deposition 
• During a floofing material carried by the river is being deposited here.
• Overtime the height of the floodplain increases
• The area is often fertile because it is made up of alluvium
• They oftern wide and cuased by meanders shifting along the meander.

This when the river meets the ocea.

• the river is tidal here.
• when there is less water, the river deposited silt to form mudflats.