Sea Level Change and Associated Landforms Flashcards
Adaptation vs mitigation
Mitigation= reducing the severity/ impact of something so that adaptation isn’t necessary
Adaptation= making adjustments to live with the problems being faced
…change is where the sea level rises or falls on a global scale (refers to global sea level change)
Eustatic
…change is the local change in sea level as a result of the land rising or falling relative to the sea
Isostaic
2 ways to describe sea level change
Eustatic
Isostatic
Eustatic sea level change meaning
The rise or fall of sea level on a global sea level (global sea level change)
Isostatic sea level change meaning
Local changes in sea level as a result of the land rising or falling
Describe stage 1 in the cycle of sea level change
During the glacial period, the climate got colder leading to more precipitation falling in the form of snow and ice (instead of rain which would then just go back into the sea) which increased the amount of ice and glacial ice there was covering the earth. At the same time, the cooling of the earth led to the hydrological cycle slowing down so any precipitation that was in the form of rain/ water was returned to the sea much more slowly and together with less water entering the sea and more water being stored in the form of ice/ glacial ice instead of in the sea the sea level fell (Eustatic sea level fall)
Describe stage 2 in the cycle of sea level change
As a result of more ice and glacial ice forming on top of the land as the climate got colder, the weight of this ice on the land caused the land surface to sink (be compressed) resulting in the sea level rising in relation to the sea (Isostatic sea level rise but also referred to as Isostatic subsidence)
Describe stage 3 in the cycle of sea level change
During the interglacial period the climate got warmer again so lots of the ice and glacial ice melted meaning more water flowed back into the sea resulting in the sea level rising (Eustatic sea level rise)
Describe stage 4 in the cycle of sea level change
As the climate got warmer and lots of the ice melted it meant that the weight of the heavy ice was removed from the land causing the land to rise back up to its original position (rebound/ readjust) resulting in the sea level falling relative to the land (Isostatic sea level fall but commonly referred to as Isostatic rebound/ readjustment)
Describe 4 stages in cycle of sea level change
Stage 1: During the glacial period the climate got colder causing more precipitation to fall in the form of ice and snow instead of water so less water was entering the sea but instead was being stored in ice/ glacial ice on top of the land (the amount of ice and glacial ice covering the land surface increases). The colder climate also causes the hydrological cycle to slow down so any precipitation that does fall as rain takes longer to flow into the sea. Together these factors mean that less water is entering the sea so the sea level falls (Eustatic sea level fall)
Stage 2: As a result of more ice and glacial ice forming on the land the surface of the land sinks (is compressed) due to the weight of the ice causing the sea level to rise relative to the sea (Isostatic sea level rise)
Stage 3: During the interglacial period the climate gets warmer causing lots of the ice and glacial ice to melt so the water that was stored in it flows back into the sea and more water entering the sea means the sea level rises (Eustatic sea level rise)
Stage 4: As the ice/ glacial ice melts this causes the land to rise up (readjust/ rebound) back to its original position as the heavy weight of the ice that was compressing it has been removed. This leads to the sea level falling relative to the land (Isostatic sea level fall but more commonly referred to as Isostatic rebound/ readjustment)
When the sea level rises the coastline is drowned leading to..features being formed e.g Dalmatian coasts, rias and fjords
Submergent
When the sea level falls the coastline is left high above sea level leading to …features being formed e,g raised beaches, marine platforms and relict coastlines
Emergent
3 key submergent features of coastline (formed when sea level rises and coastline is drowned)
Dalmatian coast
River
Fjord
3 key emergent features of coastline (formed when sea level falls so land is left high above sea level)
Raised beach
Marine platform
Relict coastlines (coastlines that are no longer reached by the high tide)