demonstrate an understanding of the work of the sea and wind in eroding, transporting and depositing

•waves are caused by wind dragging the water surface (friction) 

          •the size and and energy of the waves are determined by: the fetch, strength and duration of

           the wind

                    •wind is created by convection currents 

•coasts have the same erosion process as rivers

          •hydraulic action: force of wave hits the rock; the air is trapped by a wave in a crack and cracks it further due to hydraulic pressure 

         

          •abrasion: where rocks are picked by waves and thrown against the cliff

          •solution: where the rock is put into solution by weak acids

          •attrition: materials in the wave smash each other, becoming smaller and rounder  

•the rate of erosion occurring along coastlines depends upon the type of and strength of waves and the type of rock

•constructive waves: •created in calm weather

                                  •stronger swash than backwash

                                  •deposits material on the beach

                                  •lower in height and less frequent  

•destructive waves: •stronger backwash than swash

                                •removes material from the beach 

                                •steeper in height and more frequent

•coasts also experience transportation as material is moved across the coastline by longshore drift 

          •it moves in a zig-zag pattern

          •the backwash is supported by gravity

          •the prevailing wind reaching the coastline means there is usually a distinctive longterm direction of transportation