Eustatic - is world wide changes in sea level due to glacial erosion when water was stored on land reducing sea level.
Isostatic- Isostatic change is due to changes in loading of the crust of the earth: Loading (or unloading) can be due to mountain building, erosion or ice build-up. If material is added, the crust will sink a bit, and if it is taken away the crust will rise
Isostaic recovery complex in UK? Isostatic recovery is greatest near Scotland that is where most of ice was. The land is rising at 4-20 mm a year and in the south land is sinking.
Global warming causes the expansion of water as water heat it gains kinetic energy causing it to move faster and futher apart meaning it expands.
Global warming leads to Eustataic change.
Submergent coastline features- Submergent coastlines are stretches along the coast that have been inundated by the sea due to a relative rise in sea levels. This occurs due to either isostacy or eustacy.
Ria- during ice age sea level was lower.SO valleys cut below present sea level after these melted the valleys drowned giving Rias in hilly areas and estuaries in lowland basis.(Devon )
Fjords- found in mountainous coastal areas as glaciers cut u shapes valleys by abrasion. Glaciers cut steep sided flat bottomed valleys in low land which drowned due to sea level rise.(Howe sounds in North America)
What is an Emergent coastline-Are associated with a drop in the sea level.(raised beaches) occurs due to isostatic of eustatic change. Identify them by features above the high tide mark. Raised beaches were formed when the sea level was higher than today this can be seen in Isle of Portland which is 15meters above sea level.
Rise in sea level- Bangladesh, 1m sea rise could result in 17.5% of country to be under water leading to 13 million being displaced.
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