Coastal erosion, sometimes referred to as shoreline retreat, is the loss of coastal lands due to the net removal of sediment or bedrock from the shoreline. It can be a rapid-onset hazard (occurs in a period of days to weeks), or a slow-onset hazard (occurs over many years, or decades to centuries). Coastal erosion is a natural process caused by the force generated as the ocean crashes against the shore. Although this process cannot be effectively stopped, it is something that can be managed.
The problem of coastal erosion is that it can lead to major coastal flooding where normally dry, low-lying land is flooded by seawater as a result of several factors such as increasing sea height and the destruction of natural or artificial sea barriers by waves. Storm surges, massive waves generated by extreme weather events such as hurricanes or large storms in temperate areas, are the most destructive element when it comes to coastal flooding. With this, scientists predict that almost half of the world’s sandy beaches will have retreated significantly by the end of the century as a result of climate-driven coastal flooding and human interference. They also say that coastal erosion could endanger wildlife and inflict a heavy toll on coastal settlements that will no longer have buffer zones to protect them from rising sea levels and storm surges.
A coastal country such as Thailand has already experienced the effects of coastal flooding. Last year, a NIST Alumni wrote a report investigating how the expansion of shrimp farming in Thailand has affected the erosion of the Laem Fa Pha coastline.
Using satellite data, they were able to calculate the effects of coastal flooding on shrimp farming between 1984 to 2020. They found that the Laem Fa Pha coastline had receded significantly, with a net shoreline retreat of approximately 940m in the area where the temple, Wat Samut Chin, is located.
Using geometric data from previous years as well, they were able to observe that the rate of coastal erosion significantly increased in between the years of 1996 to 2008, the period of time where coastal erosion was the highest. However, this process has been slowing since then, and that is because organisations and village communities impacted by coastal erosion have begun implementing management strategies to protect their coastline.
So how is the larger community managing to slow down coastal erosion? By physically managing the coast in an attempt to control natural processes such as erosion and longshore drift and to mitigate the impact of waves, currents and floodings. Thailand has been implementing soft engineering strategies to mitigate coast erosion, meaning they are building up the natural coastal environment through sustainable means. Organisations like the ‘Flight of the Gibbon’ and others, have been replanting Mangrove Trees to provide ecosystems with a more sustaining natural environment, and greater protection to the shoreline. The mangrove forests which were destroyed in the past to make space for shrimp farming helped to stabilise and trap the sediment of the coastline through the complex structures of their large roots, while also filtering the water and storing carbon dioxide. This is precisely why many coastal communities have opted to rebuild their mangrove forests, and recent coastal data suggests that it is working.
The reestablishment of mangrove forests on coastlines combined with other management strategies, have helped communities slow coastal erosion in some parts of Thailand’s coastline. However, such management strategies have yet to be implemented in many other coastal areas that need further protection as they are at risk of disappearing forever. Therefore, I am asking you, the reader of this article, to become more aware of this problem and help spread awareness about coastal erosion to those around you. Coastal erosion is a concept that is easy to grasp, but many people do not fully understand what can be done in order to prevent our coasts from disappearing.
After all, the best way to effectively solve an issue is by first making sure that everyone affected is fully aware about what needs to be done in order to solve the problem sustainably.
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