Climate change has brought with it a host of environmental problems. One such problem is "coastal squeeze".

Simply put this phenomenon occurs when coastal erosion forces coastal habitats landward, and its progress becomes blocked by manmade features like sea walls, so that the coastal habitat is squeezed between the rising sea and the manmade barrier. In this article I will briefly go through some of the major causes of coastal erosion, how humans try to stop it and the effect of coastal squeeze on the inhabitants of these habitats.

Various factors are responsible for coastal erosion, such as, the force of waves especially during storms. The type of rock that makes up the coastline will influence the rate at which it erodes. The rise in sea level due to climate change means that rocks that easily erode become exposed to constant wave action. Another factor one has to keep in mind, is that when one area erodes, sediment gets deposited in another area. This occurs naturally and also when humans set up structures like sea walls to prevent coastal erosion.

Human sea defences include sea walls or earth embankments and are built in areas where coastal erosion threatens to destroy land, homes and businesses. But our planet has natural defences against coastal erosion. Some of these defences include cliffs, sand dunes and saltmarshes, which protect the coastline by mainly absorbing the force of the wave action. However, these natural defences can adapt to changes in the environment by moving more inland while artificial defences cannot. So if humans put up their own defences the migration of these inter-tidal ecosystems hit a "road block" of sorts and are "squeezed".

These protective ecosystems are called inter tidal ecosystems and not only include saltmarshes, but beaches, mudflats and mangrove woodlands. These habitats may not look very interesting and full of life but, they are very important for their function in coastal protection. They also provide other services like improving water quality and holding mud along the edges of estuaries. Some also provide a safe haven with respect to shelter and a supply of food for fish of commercial value that are exploited.

One remedy for coastal squeeze is the planting of vegetation on sand dunes. This action prevents erosion and actually encourages growth of the dune by trapping and stabilizing blown sand.

Another remedy is beach filling also called beach nourishment. For this method, sand is removed from one area and placed in another area suffering from coastal erosion. Besides ensuring the existence of the beach, and the ecosystems further inland that it protects, this method increases the recreational area along the coast.

However, beach filling is also a perfect example of how a remedial method does more harm than good. For instance, initial removal of the sand kills relatively stationary organisms that live in the sand.

It also causes the burial of plants and animals at the site of removal resulting in their death. Removal of sand can cause the water to be turbid or cloudy; the loose sand can wash into the sea by wave action. This prevents light from penetrating the water column and reaching the aquatic plants near the surface which use it for photosynthesis. These plants are food for animals which in turn become food for aquatic carnivores and so on. Removal of sand from the beach also influences the use of the beach for nesting by birds and sea turtles, therefore impacting on ecotourism. Visitors to Trinidad and Tobago come to see natural sights like the nesting of leatherback turtles. Finally removal of sand too close to the shore can result in coastal erosion.

This also leads one to consider the socio-economic impact of coastal squeeze. Many people depend on inter tidal ecosystems like beaches for their livelihood. For instance, great beaches are a good promotional point for countries that depend on tourism as their main source of income. Industries and persons that directly rely on tourism like hotels, restaurants, taxi-services, tour guides, souvenir vendors and are thus greatly affected if tourism declines. Other industries that can be indirectly influenced include the farmers that supply food to restaurants and to hotels, or textile manufacturers that produce the linens and tablecloths for hotels and restaurants and uniforms for their staff. People (both native and foreign to the area) also come to the beach to relax, to exercise, and to spend time with their families and friends, so that it affects the quality of life on a whole.

Therefore, coastal squeeze has arisen as a result of climate change, and the efforts of humans to help our natural barrier ecosystems against coastal erosion. However, this problem also draws attention to the important role inter tidal ecosystems play in protecting our landmasses against coastal erosion as well as protecting inland ecosystems from wave action and degradation.