Tourist resorts, fishing communities, farming, aquaculture, and other land uses all vie for space on the coasts of the world, and often come into conflict with each other and with the dynamic interface between land and water.
While inland areas are undoubtedly less vulnerable to coastal hazards, the coastal zone has been historically rich in resources and uniquely suited to support economic activities such as trade, industry, and tourism, attracting settlement and migration despite the elevated risks. The primary impact of human activities within the coastal zone is the displacement of natural habitat with development, an increasing problem with continued coastal population growth.
This issue will be examined in detail in Module 11 case studies. In the following pages, we will examine more closely the mechanics of coastal erosion and the human engineering strategies employed around the world to mitigate coastal erosion to sustain human land uses on the coast.
We will question each approach in terms of sustainability in the context of the dynamics of the coastal zone and the increased challenges related to climate change. Over relatively short periods of geological time, the fluctuations of sea level are primarily responsible for changes in the shape of the coasts.
Because large amounts of water are sequestered in the form of ice and snow on the land during a glacial period, and the amount of water flowing from the land into the sea is diminished, sea level drops. Around 20, years ago, during the last glacial, sea level was about metres lower than it is today.
Many areas that are flooded today were dry at that time and the global area of land masses protruding from the water was about 20 million square kilometres greater than at present. The Norwegian fjords, for example, originated when immense ice masses flowed from land into the sea and gouged out the bedrock. Scientists organize this diversity into a range of categories.
For instance, coasts can be classified according to whether their form is heavily or weakly influenced by wave action and currents.
Coasts can also be categorized by the material that they are composed of, or by how strongly the material is eroded by the sea. They can be classified, furthermore, by how well they are able to trap sediments that are brought in by rivers or currents. This ability is referred to as the filtering function of the coasts. Downloadable versions of the instructor materials are available from this location on the instructor materials pages.
If you would like your students to have access to the student materials, we suggest you either point them at the Student Version which omits the framing pages with information designed for faculty and this box.
Or you can download these pages in several formats that you can include in your course website or local Learning Managment System. Learn more about using, modifying, and sharing InTeGrate teaching materials. The Dynamic Coastline While maps typically delineate the transitions between land and sea with clear lines, in reality the coastline is much less well-defined.
This widespread erosion is due to a variety of factors, most notably: Global eustatic sea level rise that has occurred over the past century Global reductions in the supply of sediment reaching the coast due to sediment impoundment behind dams, urbanization, etc. Human activities at the coast that restrict sediment movement harbors, seawalls, groins Uses of Coastal Zone.
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