Longshore Drift and Groynes How do Groynes prevent longshore drift? TKS By: Saksham Yadav Longshore Drift and Groynes Introduction Aim: To determine how groynes prevent longshore drift. The issue: Longshore drift influences the deposition and erosion of sediments. Waves erode the coast and transport the eroded material along the coastline. Over a period of time, the material will be deposited on a beach or form a larger feature such as a spit. Groynes are structures built at equal intervals along the coastline. Their purpose is to restrict longshore drift, preventing coastal erosion. Figure 1 - Google Maps About the location: The location of the study area is Silver Beach in Kurnell Peninsula, near Cronulla. It is located in the Sutherland Shire, south of Sydney Central Business District (CBD) and just directly south of Kingsford Smith International Airport. The area also has a historical significance as it is near the landing place of Captain James Cook on the 28th of April 1770 in Botany Bay. Figure 2 - Close up of the study area, Silver beach is located just on the border of Captain Cook Drive Figure 3 - Captain Cook Monument, taken by Saksham Yadav on 25/2/14 at Botany Bay Importance of the issue: Longshore drift is a process by which sediments are transported from one place to another. When this process occurs, beaches, spits and sandbars are accreted over time. If the process of longshore drift is altered by factors such as stronger winds and stronger currents, beach erosion begins at a faster rate and this may result in many serious problems. The main stakeholders of longshore drift are resort owners. They rely on people to visit their resorts and enjoy the beach. However, if longshore drift erodes t... ... middle of paper ... ... consider some ideas of what can be done to further enhance the management of the coastal issue. Using the research action plan, I aim to acquire a sophisticated understanding of longshore drift, coastal management and implementations of coastal issues, through the research action plan. Most importantly, I will include various diagrams explaining how the process of longshore drift occurs and what implementations it has on coastal environments, accompanied by an explanation of how the issue is being managed, a detailed outline of the geographical processes involved and a discussion of the impacts of the issue and why it is important. Figure 6 - How longshore drift works (Brief). Source: Classwork image (originally from Google images) Main Findings Accompanied by detailed insights into the issue Geographical processes involved in longshore drift: Bibliography
Method(data collection) ----------------------- If Long Shore Drift were taking place, I would expect to find: * Deposition of pebbles on one side of any obstruction. This obstruction could be a headland or an artificial barrier such as a groyne.
Depending on the type of path that was created, it would largely influence the rate and distance to which the sediment was transported.
Investigating the Geographical Processes that are Affecting the Physical and Built Coastal Environment There are three geographical processes that are affecting the physical and built coastal environment, they are; erosion, deposition, and transportation. Erosion is the group of natural processes, including weathering, dissolution, abrasion, corrosion, and transportation, by which material is worn away from the earth’s surface, this is mainly caused by wind, running water, and waves breaking on the coast. Deposition is the depositing something or the laying down of matter by a natural process. Transportation is when sand is moved along the coast by long shore drift. At North Cronulla beach erosion is evident.
coast (as shown in pictures 1 & 2). The area of sea is subject to the
This shows that it is eroded at one end more which is a sign of long
See Location Map of the coastline being studied from Herne Bay to Reculver.
There are many different types of coasts that exist throughout the United States. The south shore of Long Island has a unique types of coast known as a barrier beach. Barrier beaches are long narrow land forms that are composed of sand and other lose sediments. These sediments are brought together by the actions of waves, currents and storm surges. Barrier beaches are subject to constant changes by the same forces. Sand is constantly eroded in one area an deposited in another. Barrier coasts are important for a number of reasons; they protect the mainland of Long Island from the open ocean and flooding during storms, for recreational use and the unique ecosystems which exist on barrier beaches.
walking across them. The lines and pulleys and some parts of the waves are example of
Over the past 100 years the Louisiana coastline has suffered greatly from biotic, abiotic, and anthropogenic factors. The abiotic factors include things such as hurricanes or overnutrition that influence the surrounding biota. The biotic factors that contribute to coastal erosion are things like the immigration invasive species and the emigration or extinction of local flora and fauna that help preserve the wetlands. Additionally, there are anthropogenic factors such as pollution that can have strong negative influences on the abiotic and biotic factors of the wetlands. Each one of these factors cause ecological disturbances to the wetlands at a frequency and intensity that is unmanageable for the local flora and fauna. There are currently certain measures that are being taken into consideration to slow or stop the erosion of the Louisiana coastline.
cut back on the problems in the Bay. Scientists have given an unthinkable amount of attention to the Bay of the past several years and researchers from countless numbers of agencies and institutions have dove deep into the issues and studying every nook and cranny to create answers to every politicians’ questions. The biggest concern with the Bay, and the most concentrated ...
Coastal erosion is a growing problem along the Gulf Coast. Louisiana is one of the coastal states most affected by coastal erosion. Ninety percent of wetland loss in the nation occurs in Louisiana, losing 25-35 square miles per year. At that rate, Louisiana will lose 640,000 more acres by 2050. Many factors contribute to this land loss, such as rising sea levels, subsidence, hurricane storm surge, cold fronts, and human interference. Cold fronts and hurricanes can both have detrimental consequences on the coast of Louisiana (Zhang 2004) (Restore or Retreat 2012). This research shows whether cold fronts or hurricanes have a larger effect on coastal erosion. The researcher will describe how historical and current satellite imagery help in determining the changes in the Louisiana coast. Based on previous research, the researcher believes that hurricanes have more of an effect on coastal erosion than cold fronts due to the high winds and storm surge.
Today, with our understanding of how fragile the coastal areas are, there are many study and restoration projects underway. Since the implementation of the Coastal Wetlands Planning, Protection, and Restoration Act (CWPPRA) in 1990, there have been 151 coastal restorat...
Point cartwright is located on the coast of south east Queensland and stretches 100m. It has a diverse environments such as sand
Climate Change and Global Warming cause sea levels to rise. This increase in sea levels not only causes inundation of low lying and coastal areas but also irrevocable damage to coastal environments. Globally the ocean is predicted to rise nearly 140 cm on a global scale by the year 2100 (Cooper et al. 2013); therefore this has massive implications for countries all around the world with cities (settlements etc.) based near bodies of water. When compared to the last 80 years this is an acceleration of nearly twice the rate that ...
People from all over the world go to beautiful beaches that are filled with water as clear as ice or as beautiful as diamonds. But, what will happen if we do not conserve the appealing sites that draw attraction to the public? Contaminated beaches has become a controversial issue to the public because of the causal problem, the harm to the people and marine animals, the government agencies supporting or opposing pollution, and the industries involved in creating such unlawful decisions. To create and find a solution, we must first find the core to the problem.