Geography AS Unit 1 – Dynamic Landscapes Coastal Landscapes and Change Summer Work (Mrs Ellis)
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Geography AS Unit 1 – Dynamic Landscapes Coastal Landscapes and Change Summer Work (Mrs Ellis) Unit 1 Dynamic Landscapes 1) Tectonic Processes and Hazards – This unit looks at natural hazards (their frequency, distribution and trends), and how to manage them. 2) Coastal Landscapes and Change – This unit looks at coastal processes, landforms and landscapes, coastal risk and how to manage them. Over the summer, I would like you to do some work on coastal landscapes and change Coastal Landscapes – Research Do some research on the different types of coastal landscape. Consider the following points: Erosional v depositional Cliff v sandy v estuarine Different types of geology Emergent v submergent Land use Tidal range Wave energy Concordant and discordant Present your findings in an interesting way to share with the class. This can be a PowerPoint, video, colourful mind map etc. Use pictures and maps in your work. Coastal Landscapes – The Players/Stakeholders There are a number of groups (players/stake holders) who are involved in coastal management DEFRA (UK) Ministry of defence Local councils Lands owners Local people Environmental groups Other organisations e.g. RAMSAR, UNESCO, NNR Large companies e.g. oil companies Find at least one example of each of these. How have been involved in managing coasts. Used named locations in your answers This work should be presented as a table. (headings – Player/ responsibilities/ possible conflicts/ located name example with details/sources). Example headings for task 2. Player/ Responsibilities Possible Detailed located example Sources e.g. websites/ Stakeholder conflicts/ issues involving this player books /articles with other stake holders Eg Defra Useful Websites and clips https://www.s-cool.co.uk/a-level/geography/coastal-processes https://www.bbc.co.uk/programmes/b006mvlc (BBC coasts) https://www.bbc.co.uk/programmes/b006w6xh/clips (short clips) https://www.geography-fieldwork.org/a-level/coasts/ https://www.gov.uk/government/organisations/department-for-environment-food-rural-affairs https://coast.noaa.gov/czm/ Useful reading Geofactsheet 141 – The Holderness Coastlines Geofactsheet 356 – coastal erosion Landforms on the Gower Peninsula Geofile 491 – Coastal erosion – East Yorkshire Geofile 537 – North Norfolk coast Shoreline Management Plan Geofile 575 – Coastal Systems Geofile 585 – Pressures on the Coastline Geofile 600 – Sea level change: Causes and coastal landforms Geoactive 510 – Managing conflicts in Poole harbour Geoactive 542 – Sand Dune Management, Merseyside Useful Unit Guide: https://www.amazon.co.uk/Edexcel-level-Geography-Student-Guide/dp/1471863158/ref=pd_sbs_14_3/259- 9953827-8091026?_encoding=UTF8&pd_rd_i=1471863158&pd_rd_r=100690a3-9759-11e9-9696- 83bafaaed3b7&pd_rd_w=JQfwV&pd_rd_wg=JxZ9M&pf_rd_p=18edf98b-139a-41ee-bb40- d725dd59d1d3&pf_rd_r=C50R8YMGNMTKNDZ9WPHE&psc=1&refRID=C50R8YMGNMTKNDZ9WPHE For each piece of work please credit your sources – those above and any of your own. Try not to use Wikipedia but stick to websites run by governments, academic sites, appropriate charities and organisations, and quality news sites And finally Over the holidays read a good quality newspaper or check the BBC website for news on the environment and/ or Science. Make a collection of articles that are related to Geography. Keep these in a folder. JANUARY 2005 Online 491 Geofile Mike Wynn Landforms of Coastal Erosion: Examples from East Yorkshire Introduction Figure 1: Coastal systems The coast – the interface between land INPUTS PROCESSES OUTPUTS and sea – is a worldwide linear zone, often only a matter of a few metres Wave Landforms of energy erosion wide. In Britain we often think of the Processes of coast as being formed by the energy of wave erosion the waves, largely due to their Geological Landforms of Transport ubiquity and power; however, sub- structure deposition aerial processes are also significant; Mass movement sometimes climatic regimes are Sub-aerial important and also vegetational activity processes on some coasts. Coastal defence – Human Hard/soft holding the line The coastal zone can also be viewed as activity engineering of retreat a system, with inputs, processes and outputs) (Figure 1). Wave Energy The Processes of Coastal enter a tiny crevice or large cave and air is trapped, then forced into Waves are pockets of energy Erosion all the weaknesses, time after time, generated by the wind; consequently Waves are affected by friction as the so that the rock can eventually the fetch of a wave is significant. In body of water moves forward and the collapse. the North Sea, wind can blow from energy within becomes a major • Subaerial weathering This occurs the Arctic directly southwards, erosional process. most notably by rain leading to generating storm waves that attack • Abrasion (Corrasion) Waves the saturation of cliff material and north-facing sections of the East throw loose sand and shingle and then the failure of the cliff by Coast such as Whitby, Flamborough even boulders at the cliff; this is mass movement. This mass Head, and the north Norfolk coast. one of the most effective methods movement can range from soil On a global scale, winds blow across of erosion. A hard cliff face creep, to slumping, to landslides. the Atlantic Ocean from the south becomes smoothed and even This is an important process on west, creating swell that reaches the the upper part of the cliff and in Cornish coast. undercut to create a notch; a cliff face of alternating hard and soft softer material. rock becomes indented Depending upon preceding weather (differential erosion). Factors Affecting Coastal conditions over the surrounding sea • Attrition This is where all Erosion area, waves arrive at the coast with a movement of the water turns number of characteristics: wave rocks, boulders and gravel into Geological structure height, wave period, wavelength, wave smooth, rounded, smaller rocks, All rock has degrees of hardness or velocity and wave steepness. The usually between high and low tide. softness. Boulder clay is much softer combination of length and height • Solution (corrosion) This takes than chalk, so the former will erode to determine the amount of energy: E = place where carbonic acid in sea form a bay, the latter will be resistant LH2, so a small increase in height and form a headland. However, the water reacts with CaCO3 in gives a large increase in energy. limestones, or the salt in sea water same features will result with two and spray corrodes rocks, similar rocks eg limestone, providing As waves approach shallow water, especially if salt crystals grow and one is harder than the other. friction with the sea bed increases, so cause rocks to disintegrate. the height and steepness increase, • Biological activity Secretions Within the rock it is necessary to causing the crest of the wave to ‘fall from algae attack rocks, and some recognise some common structural over’; this is when the wave breaks, molluscs can bore holes in rock. features. All sedimentary rocks are water rushes up the beach as the • Wave pounding (Waugh), wave laid down in layers called beds or swash and returns by gravity as the quarrying (Knapp) Waves impact strata, one layer being separated from backwash. Under calm conditions the the rock face with pressures of up the next by the bedding plane. frequency of waves (wave period) to 50kg/cm2 (cf. car tyre 2kg/cm2) Within beds are joints, the result of ranges from 6 to 8 per minute, but (Knapp). The effect of this is to lithification (soft sediment turning under storm conditions this increases loosen blocks of rock along any into hard rock). Bedding planes and to 10 to 14 per minute, with a weakness. This process can joints are weaknesses within the rock commensurate increase in the amount eventually destroy sea walls. and are likely to be exploited by of energy expended on erosion. • Hydraulic pressure This is often processes of weathering and erosion unseen, but very effective. Waves (Figure 2). Geofile Online © Nelson Thornes 2005 January 2005 no.491 Landforms of Coastal Erosion: Examples from East Yorkshire Figure 2: Some structural terminology direction at 4º; they are well jointed and criss-crossed by minor faulting – Joint all the necessary ingredients for erosion. Bed Geological history The recent geological history of the area is important. Pre-glacially the Bedding plane Stratum (pl. strata) cliffs were only made out of chalk and were about half their present height. The sea eroded caves, arches and Alternating layers of rock range stacks and a wave-cut platform. F = fault from ‘massive’ (very thick) to only During the Ice Age the whole of this a few centimetres thick. area was covered in ice; post-glacially, as the ice retreated, a vast deposit of Boulder Clay was left over all the area, Figure 3: Cliff profiles masking pre-existing features: the Horizontal strata Inland dipping strata Seaward dipping strata caves were plugged with Boulder Clay and the bays were infilled. As the North Sea basin filled up and the Soft waves rolled in, their first job was to excavate the Boulder Clay, to reveal Hard Sea Sea Sea many of the original features. level level level Notch Selwicks Bay In Selwicks Bay, most easily eroded by the sea are the faults, which (a) (b) (c) enlarge into caves. In places, two caves erode back to back to form a through-cave, or a cave can erode Igneous rocks also exhibit joint the foot of the cliff, causing maximum through a small headland into a pre- patterns, as in the hexagonal columns erosion. Some waves at high tide may existing bay, both of which are called of basalt seen widely throughout cross the wave-cut platform and not arches. Some arches are so small it is Iceland and on the Giant’s Causeway be much affected by friction and then only possible to crawl through them, in Antrim, Northern Ireland. refracted by the cliff, having minimal others are large enough to sail a yacht erosional impact.