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Coastal Change

The coastline changes shape over time through natural processes, with climate change, human activity and existing flood defences also having an effect. The shape of our coastlines is changing rapidly, putting many homes, businesses, and coastal communities at risk of flooding and abandonment.

Introduction

Coastlines naturally erode over time causing them to retreat inland, and climate change is causing sea level rise and larger, more frequent storm surges. This all increases the risk of coastal flooding which affects coastal communities and infrastructure.

Coastal flood management is therefore needed to manage the risk of erosion and flooding. Coastal flood management techniques can include hard defences such as sea walls, and soft defences such as dune planting and managed realignment.

 

Coastal Change

The coastline changes shape over time through natural processes, however, climate change, human activity and existing flood defences also have an effect too. The shape of our coastline is changing rapidly, putting many homes, businesses, and coastal communities at risk of flooding and abandonment.

 

Natural Processes

Longshore drift is the natural process by which sediment and material is moved along the coast at right angles by wave action. This shapes the coastline by removing material (erosion) and depositing it elsewhere (accretion).

 

Human Activity

The coastline can draw in many tourists and provide economic opportunities for the tourism industry. Seaside towns have been developed over many years to create shops, hotels, piers, and roads on land that was once intertidal. Human activity in these areas can damage the effectiveness of sand dunes.

 

Reclaimed Land

Land reclaimed from the sea enables development closer to the coast. Sea walls put up to protect the reclaimed land slow coastal erosion and therefore influence the shape of the coast. On the other hand, managed realignment schemes set back flood defences further inland to create intertidal habitats in the form of mudflats and salt marshes. These coastal marshes help to dissipate wave energy and protect against coastal flooding and erosion.

 

Climate Change

Our climate is changing, and the Earth is heating up. As a result, the ice caps are melting, and thermal expansion is causing sea levels to rise. Over time, higher sea levels may speed up erosion and inundate coastal land. Climate change is also affecting weather patterns, causing an increase in wet and stormy weather. Larger and more frequent storm surges can speed up the rate of coastal erosion and increase the risk of flooding.

Find out more about the impacts of climate change in our resource here.

 

Flood Risk Management Schemes

Some flood defence schemes that are put in place can influence the shape of the coastline by preventing the natural processes of coastal erosion and accretion, for example, sea walls. Schemes that involve the mimicking of natural methods to manage flood risk, such as beach nourishment, replaces material that has been lost by the sea or wind to try and replicate the natural changing of the coastline.