Beach Erosion in Southern California

Wind and waves affect Glenelg as they set up a northward drift of sand along the coast and this type of sand movement is known as littoral drift. During coastal storms, huge quantities of sand are eroded and this does damage to near shore, beach and sand dune areas. Glenelg is not considered to be a stable as beach as many others are. Seagrass loss and seabed instability that affect Glenelg is that a third of seagrass meadows along the coasts of Glenelg has died since 1950 and poor water quality resulting from the stormwater runoff and effluent disposal has most likely been the initial cause. When there are gaps in the seagrass meadows the sand below the meadow edge can be eroded by the waves and this will in turn increase the rate of seagrass loss and make it difficult for plants to recolonise the seafloor, even though the water quality has been improved. Sea levels affect Glenelg as parts of Glenelg are being subsided as a result of climate change and a relative sea level rise of one to two millimetres per year has been recorded for Glenelg. “As a result of the loss of sand from the seabed, the level of the seabed has steadily become up to one metre deeper and the wave energy reaching our beaches has increased.” (Adelaide’s Living Beaches Strategies,

Seawalls are also strategies that Cronulla and Collaroy implement on their beaches. However, the seawalls in Collaroy are buried under the sand and are only visible after large-scale erosion events. Whereas Cronulla beach’s seawalls are visible and reduce the scenic

Sand dunes are a valid indication of the quality of the soil and the surrounding ocean. When vegetation is established in sand dunes, it stabilises it- i.e. gives the dunes structure. This structure helps prevent erosion by using the plant life to trap the sand. Without these plants (and ultimately the sand dunes) sand will be subject to many natural forces without protection, meaning any major storm could theoretically remove large amounts of sand from the beach with no natural means of replenishing it. Long Reef Beach is commendable in the amount of vegetation it has produced.

The Year 10 geography field trip was an insightful experience into the workings and functioning of metropolitan coastlines here in South Australia. The day consisted of visiting various beaches in Adelaide that were influenced by some form of hard or soft engineering techniques that changed the natural processes of the beaches. What was evident from this trip was how much these beaches have been changed to an extent where it is unlikely that they will ever go back to the way they were prior to human settlement.

At Nudgee Beach, erosion was found to have occurred on the edges of the mangrove forest and along the mudflat shorelines. Erosion is typically influenced by natural factors and occurs when pieces of weathered rock or soil are moved – typically by wind and water – from one place to another. Shorelines with lots of sediment and sand are more inclined to be effected by erosional progression. Erosion may also be provoked and accelerated by human interference. For example, if the decision to clear trees and plants from an area is made, erosion is likely to occur as the root systems of plants work to hold the soil in place. If these root systems are removed and erosion does occur, environmental conditions – such as; landslides and flooding – are more likely to take place. Erosion may also cause other plants to tip over, have their underground roots exposed and damaged and contribute to the pollution of local waters; as a result of mud and soil runoff [26]. Erosion at Nudgee Beach was likely to have been influenced by natural factors; however, the development and extension of the Kedron Brook golfing course may contribute to the acceleration of erosional processes and further damage the mangrove

Erosion is unfortuanately present at Cronulla beach, the local government have tried to tackle this problem with solution such as dune stabilization and rip rap

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

coast at a grazing impact angle. This shows just how rare Sandy was compared to

9. What are the different types of shorelines? Describe each type briefly. There is a rocky coast, lowland beach and barrier island, as well as coral reef. A rocky coast describes the most common type of costal area. This is where there are vertical wave cut cliffs and horizontal bench cut cliffs. The erosion undermines the cliffs and sends the resulting debris into the ocean forming rough outcroppings. Beaches are not only the sand

emerging breakwater and armor the beach. While this would certainly protect the beach from further erosion, it would also disturb the wildlife preservation and the turtle nesting habitat.

The erosion of shorelines is a natural process that can have beneficial or adverse impacts on the creation and maintenance of habitats. Sands and gravels eroded from the shores of coastal bays maintain the beach as a natural barrier between the open water and coastal wetlands. Beaches move back and forth onshore, offshore and along shore with changing wave conditions. The finer-grained silts and clays derived from the erosion of shorelines are sorted and carried as far as the waters of wetlands or tidal flats, where benefits are derived from addition of the new material. However, excessively high sediment loads can smother submerged aquatic vegetation beds, cover shellfish beds and tidal flats, fill in riffle

Mr. Lima and Dr. Becky Gillaspy gave some great examples in explaining the types of shorelines and its effects of deposition. During Mr. Lima’s video “Types of Shorelines,” I learned many kind of shorelines, but the one that stood out to me the most was steam deposition shorelines because it reminded me of Galveston Beach. The one time I went to Galveston, I remember every time a large wave came it carried old settlements along with it. According to Dr. Becky Gillaspy in her video “The Effects of Deposition on Shoreline Features,” the settlements I was experiencing was longshore drifting that transport settlements and sand along the cost. Also, I was able to determine that the reason why Galveston landscape has changed over the years was due

¬¬Climate change has caused dramatic changes in landforms around the world, and beaches have received much of the worst consequences from this. Alongside this, human development has kept on expanding, especially into previously “pristine” environments, thus removing “access” to a great deal of the sand that was in the area. Human expansion has also resulted in the introduction of exotic or invasive species of flora, that may have impacted the native vegetation that existed on the beachfront, and as a result, changed the structure of the pre-existing sand. This is generally due to the exotic species impacting the food web, and spreading very quickly, likely due to having many seedlings or having few predators in the new environment.

As the earth’s oceans become warmer, they expand, causing sea levels to rise. As the temperature continues to rise, sea and land ice which together hold more than 70% of earths fresh water are rapidly melting. Polar ice sheets are currently losing 268 Gigatonnes of mass every year and Arctic sea ice is disappearing at 13.3% per decade, with climate scientists predicting that by 2050 the Arctic Ocean will be completely ice free in summer. This will have huge environmental impacts, endangering countless of species and changing currents and weather patterns. This rapid change will destabilise the climate, resulting in extreme and more frequent flooding, drought, rainfall, storms and wildfires. Unless there is a change in the overindulgent and unsustainable way in which we are living the future of planet earth looks bleak.

The forms of sand dune could throw light upon the sand supply in a given region.