Explain how hard engineering can reduce the risk of cliff collapse

Hard engineering techniques are typically used to protect coastal settlements. They are used to deflect the power of waves. These are highly visible solutions which help reassure coastal communities. However, they are are expensive to install and maintain. In addition to this by installing hard engineering solutions in one place this can have a detrimental effect further along the coast.

Sea walls aim to protect the coast by by shielding it with concrete, steel and stone. Some sea walls are recurved, like the one shown in the video of Scarborough sea defences below. The aim of the lip is to deflect the energy of the wave. They are effective in protecting cliffs from erosion and also act as a barrier to prevent flooding. The disadvantages of sea walls are that they are expensive to construct and maintain. They also create a strong backwash which can erode under the wall. 

land

explanation:

australia is the flattest continent, and it has vast plains.