1.1.8 - changes to the landscape over different time periods

rapid changes to the cliff profile

• a more vertical cliff

• cliff recession

• wave cut platform forms

• more cracks/faults

summer beach profile

• shallower gradient

• more vegetation

• constructive waves

• berm

• low energy

winter beach profile

• steeper gradient

• less vegetation

• destructive waves

• sediment moved to an offshore bar

• higher speed winds

what are seasonal changes

these are things that change in the beaches profile due to the time of year it is e.g. winter or summer

what are rapid chnages

these are things that change the beaches profile due to things like storm events

what does it mean that the sea level changes are relative 

they are either due to and increase in the volume of water or the upward movement of the land

marine transgression 

where there is a rise in sea level so it flows over previously exposed land 

what is marine regression

when the sea level falls and exposed land that was previously covered 

what type of change are sea level rises

slow - it happens over millenia

how long is a milenia

1000 years

causes of sea level rise

• sea level rises 

• land subsides 

• amount of ice on the land 

causes of sea level fall

• the land rises 

• glacial period

how could the land rise

natural hazard e.g. earthquake

what is a eustatic change

a global change that happens over a long period of time

what is an isostatic change

a local change

factors controlling sea level rise 

• amount of ice on the land

• thermal expansion

• tectonic events

• human activity

amount of ice on the land 

when we enter an interglacial period and so the glaciers melt and the volume of water in the ocean increases

• eustatic

thermal expansion

warmer water expands and take up more space so sea level rises

• eustatic

tectonic events

movements of plates push up the rock at the bottom of the ocean which raises water levels 

• isostatic

human activity

the industrial rev increased carbon emissions which increases temp and so we get warmer oceans 

• eustatic

glacioisostasy

• when glaciers are present the weight of the ice depresses the underlying rock and the mantle flows outward 

• when the glaciers melt the rock rebounds and flows upwards 

emergent landforms

relative sea level fall

submergent land forms

relative sea level rise

an example of a submergent landform

fjord