Water is not given enough credit for the role it plays in shaping Earth. Tectonic plates and volcanic eruptions are often cited as the culprits for most land features, but it is water and wave action that shapes our world’s coastlines. When a wave crashes on the shore it carries sediments that are suspended in the water, and it pushes larger sediments along the ground too.
When a wave recedes it also takes sediment with it, but rarely at an equal
rate. If a wave deposits more sediment than it takes away then this sediment builds up, causing coastlines to extend. Conversely, when more sediment is being removed than added, the coastline recedes or
erodes. Coastal erosion is responsible for some of the most amazing landforms we know today, from the Twelve Apostles in Australia to the White Cliffs of Dover in England. The type of coastline that is
created from erosion varies greatly depending on any number of factors, including the strength of the wave action and wind, the sediment composition of the coastline and the types
of nearby rock.
Coastal erosion is a very slow process, taking hundreds of years, but scientists believe that climate change is speeding things up. Climate change has caused a rise in sea levels and storm frequency and severity – both of which play a key role in erosion. Indeed, the UK’s Environment Agency estimates that the British coastline could erode from 67-175 metres (220-575 feet) over the next 100 years.
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