Coastal risk Flashcards
Isostatic change
a local rise or fall in land level
Eustatic change
involves a rise or fall in water level caused by a change in the volume of water, this is a global change, affecting all the world’s connected seas and oceans
Accretion
when sediment is added to a landform, such as a river delta, by deposition, can build to form new land, delta can grow out to sea, tends to be balanced by subsidence, caused by weight of the newly deposited sediment
Post-glacial isostatic adjustment
the uplift experienced by land following removal of weight of ice sheets, sometimes called post-glacial rebound or post-glacial re-adjustment
Ria
drowned river valley in unglaciated area caused by SLR flooding river valley, making it wider than would be expected based on river flowing into it
Barrier island
offshore sediment bars, usually sand dune covered, not attached to the coast, between 500m and 30km offshore, can be tens of kilometres long
Dredging
scooping or sucking sediment up from the seabed or river bed, construction sand or gravel, or to deepen channel so large boats can navigate it
Dissipation
how the energy of a wave is decreased by friction with beach material during swash up the beach, wide beach slows waves and saps their energy so, when they break, most energy has gone
