Explain why coastal California is considered a disaster hotspot? (15marks) A disaster hotspot is a country or area that is vulnerable/ disaster prone due the hazards that are; Geophysical, hydro- meteorological. A human factor that increases the risk is vulnerability which includes- population density, wealth and GDP (gross domestic products) which affects the impact of the natural hazard. California is considered a disaster hotspot as all of these factors contribute to an increased danger to human life, meaning it is susceptible to the following natural hazards: earthquake, tsunamis, volcanoes, droughts, wildfires, fog and smog, hurricanes and landslides. One hazard can often trigger others (e.g.
The Negative Effects of Hard Stabilization Hard Stabilization is the act of building any structure on or near the water in order to interrupt the natural flow of the surrounding water to “preserve” an area. The act of building on barrier islands alone is an awful idea, but building hard stabilization in order to maintain the already built structure just makes problems worse. Hard stabilization displaces sand, destroys marshes and beachfronts, and is extremely cost inefficient. The building of groins and jetties causes major damage to the surrounding beach front by interrupting the Long Shore Current. The Long Shore Current is a current that runs parallel to the beach front taking sand with it which causes sand to be constantly moved in a certain direction.
Each chapter in the book blends lucid, factual explanation of complex subjects with engaging chronicles of the author’s travels to far-flung parts of the globe. Human activity is altering the ocean in every way, from temperature to salinity, from acidity to circulation. “ Each of these changes not only drastically affects the marine world, but more alarming has dire consequences for all life on earth”. (p.6) She convincingly makes the case that the oceans are an integral part of the climate change dilemma and need to be addressed along with changes in the atmosphere before a climate tipping point is reached. Clear and easy read of the current state of our Oceans.
When we look at weathering and how it influences rocks, it can be divided into two categories. These categories include mechanical and chemical weathering. In each of the processes that make up both mechanical and chemical weathering, there are factors that affect the rate in which a rock will break down. In fact, the factors that impact the rate of weathering include the rocks characteristics and the climate. Also, both mechanical and chemical weathering aid in the development of spheroidal weathering.
Foredune and Second dune For the natural processes, Foredune and Second dune both are influenced by the seasonal wind, waves and parent rocks form Port Phillip Bay. During the flooding period from Port Phillip Bay and hardened into sedimentary rocks consequently, Foredune was formed as sediments washed from land by waves where eroded to form the underlying bedrock of the area (Gregory 1912) In terms of temporal scale, the pattern and shape of Seaford Beach influenced by seasonal alternations in dominant waves, which affected by two different directional wave during summer and winter months (Bird, 2011) There are gently curved beaches on coasts of Port Phillip Bay shaped by locally generated waves instead of received ocean swell (Figure 4) Although the beach materials, like sand and seashell, are removed seaward by storm waves, the coast outlines would maintain the smoothly curved shapes when the shape is established (Bird,
At North Cronulla concrete footpaths were built on existing sand dunes. However, the natural process of sand erosion caused by the waves hitting the beach undermined the pathways and they started to collapse. To halt the erosion large river stones were placed underneath the length of the path to create a base on which interlocking honeycomb shaped bricks were concreted into place. A continuous sloping retainer wall was built that is approximately 330 metres long. The retainer wall has remained in place because it withstands the continual flow of water and wind erosion.
Over time weathering takes over the igneous rocks. Sediments from the weathered rocks moves downward by running water, wind, waves, and many other erosional agents. The next step is lithification. The sediments become tightly packed down in the depths of earth and encounters massive amounts of pressure and heat. A metamorphic rock is now formed.
Which makes them significant to economies. The Pacific ocean, because the plates plunge beneath the mantle in this area. Hydrogenous sediment is formed when minerals crystallize in ocean water due to many types of chemical reactions. They come from trenches and shelves. They are used for making concrete.
The movement of the plates is divided in three ways: they move together (converge), the move apart (diverge), or they move past each other [About.com – Geology]. “Earthquakes occur along faults, where huge blocks of rock are grinding past each other. Tectonic motions produce directional pressure, which causes rocks on either side of a large fracture to move past each other. The movement is rarely smooth; usually the blocks stick because of friction, which slows their movement. Eventually, the friction is overcome and the blocks slip abruptly, releasing pent-up energy with a huge “snap”—an earthquake” (The Plate Tectonic Model – Page 107).
The Forces that Change the Face of Earth Despite our tendency to consider Earth as static, it is actually a dynamic and ever-changing planet. Wind, water, and ice erode and shape the land. Volcanic activity and earthquakes alter the landscape in a dramatic and often violent manner. And on a much longer timescale, the movement of earth’s plates slowly reconfigures oceans and continents. Each one of these processes plays a role in the Arctic and Antarctica.