Geographical Processes

 Physical processes include erosion which is a result of the forces of wind and sand impacting on rocks and sand. Soft rock and sand is washed away, while hard rock remains behind. Long shore drift has a large effect on erosion in the Lake Cathie area, as it is one of the most important processes that operate in the coastal environment. Longshore drift is when waves approach a beach at an angle, then gravity causes them to travel directly back towards the ocean. The backwash is then hit by the next wave and the process begins again. Longshore drift along the Lake Cathie coastline is removing 6m of sand per minute. This is because there are more destructive wave than constructive waves at Lake Cathie, this means the beach will keep eroding away. Destructive waves remove sand from the beach and take it into the water, at which longshore drift removes it permanently.  Constructive waves put sand back onto the beach.

 There are also human geographical processes operating along the lake Cathie coastline, like the building of infrastructure on the hind dunes, the removal of vegetation and human trampling.  The building of infrastructure such as roads, houses, shops and car parks, meant that the dune had to be flattened in order to build. The removal of vegetation is not a good thing. The vegetation on the dunes holds the sand in place and gives a dune less of a chance of eroding away. Human trampling on the dunes causes the erosion problems to escalate, because they are knocking down all of the sand and wrecking plants that hold dunes together.