A Level Geography – Year 13.
Coastal Systems and Management.
Where do coasts fit into the examination
system?
Skills covered and developed
Fieldwork
“Road map” of this part of the course:
CW Date: 6th September 2017
How is the systems approach
applied to coastal studies? - 101-105
Try to identify the exact location from which the photograph was taken.
Systems are ways of thinking and
understanding natural processes, relationships and changes. A systems diagram
shows the different components of natural environments and the links between
them. The components of a system include:
o
Inputs
o
Stores
o
Outputs and
o
Flows and transfers
These elements have been encountered as
part of your studies of the carbon and water cycles.
Systems can be viewed as open or closed.
Closed systems receive no inputs from
outside the system, except for energy, and have no outputs from the system…
again, excepting energy.
Open systems, however, receive both energy and material inputs and produce both energy and material outputs from the system.
Open systems, however, receive both energy and material inputs and produce both energy and material outputs from the system.
The coast is an example of an open system…
for example, sediments can be received from outside the system e.g. material
brought down rivers and deposited at the coast. They also produce outputs to
different systems such as eroded rock material that is transported into the
deep ocean.
Action:
1.
Refer again to the photo, figure 1 on
pp 102 showing Selwicks Bay, Flamborough Head.
2. Briefly describe it using appropriate geographical
vocabulary.
3.
Consider the following
components illustrated:
a.
Small stream discharging water
and sediment into the sea.
b.
Waves approaching the shore
formed by weather systems in the North Atlantic.
c.
Erosion of cliffs liberating
sediment.
d.
Transportation southwards of
sediments by LSD.
e.
Transportation off-shore by
currents.
4.
Decide whether each of the
above is an input, an output or a store.
5.
As an open system, the coast
has important links with other natural systems such as the atmosphere, tectonic
activity, ecosystems and oceanic systems through flows of energy and transfers
of material. Describe and explain examples to illustrate these links.
CW Date: 11th September 2017
Coastal Sediment/Littoral Cells
Entry discussion - In pairs/threes:
Discuss examples of positive and negative feedback loops in nature and also any examples of dynamic equilibrium that you can identify/recall. Try to refer to the processes that create these features of physical systems.
Key Vocab:
Introduction:
In common with other natural systems it is useful to apply systems terminology to help us understand the connections between processes and landforms (see figure 3, pp 103 and above).
In common with other natural systems it is useful to apply systems terminology to help us understand the connections between processes and landforms (see figure 3, pp 103 and above).
A good example of the systems approach
applied to coasts, is the sediment cell (Fig. 2 pp 103 and right). Within a sediment cell
there are clear inputs of sediment from rivers and cliff erosion, transfers by
longshore drift of sediment, stores in the form of beaches and spits and
outputs due to transfers into the deep ocean by off-shore currents.
Action:
Complete the activities 1, 2 and 3 on pp
105.
Source Sheet (Q.1.) - Here
Flipped Learning:
Go to the New Zealand Ministry for Primary FIsheries (www.govt.nz) and find out why the range of New Zealand's fisheries is of particular interest to marine ecologists (See also source sheet provided - above).
Starting point HERE
Will need to research/delve and draw own conclusions...
Source Sheet (Q.1.) - Here
Flipped Learning:
Go to the New Zealand Ministry for Primary FIsheries (www.govt.nz) and find out why the range of New Zealand's fisheries is of particular interest to marine ecologists (See also source sheet provided - above).
Starting point HERE
Will need to research/delve and draw own conclusions...
CW Date: 12th September 2017
Title: Sources of energy at the coast - 106-108
Entry Task:
Outline, in writing, the difference between waves and tides.
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The most obvious manifestation of energy at the coast are waves. These are ultimately formed by energy from the sun that causes differences in surface pressure and thus leads to the movement of air in the form of wind. Wind, blowing across the water surface, results in frictional drag. This disturbs the surface of the water, forming ripples and, in time, waves.
- In the UK, the prevailing wind is from the south-west due to air moving from the sub-tropical high pressure belt (around 30 degrees North) to the sub-polar low pressure belt around 60 degrees North (Wind is simply air moving from areas of high pressure to areas of lower pressure along a “pressure gradient”.
- The steeper the pressure gradient, i.e. the greater the difference between the two areas of pressure, the stronger the wind.
- The wind blows over the Atlantic Ocean transferring considerable energy from the Sun to ocean waves and ultimately impacting on the UK shoreline.
Wave energy is affected by the following factors:
- The strength of the wind - the stronger the wind, the more powerful the waves.
- The duration of the wind – the longer the wind blows, the more powerful the waves.
- The fetch – the distance of open water over which the wind blows. The longer the fetch, the more powerful the waves.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhCl0NZtJd_cPT-n7km5m_EhiFpmR4gZE9ResO9Mx7XJU57h9k9l1wnIpoxuqiV4Xn_cVaG_Uq1a60hGl41dH5BGphCm0ZYD6ULlr7F7XoiqBByQ9qyvx9PZnzRas-AwlAEJgm2M772Hi0/s400/Picture7.png)
Action:
Completion of the 4 activities below for Thursday 14th September.
1. Using annotated diagrams as well as narrative, explain the formation and form of waves by wind.
2. How do wind formed waves differ from those formed due to, for example earthquakes or submarine landslides?
3. Describe and explain the changes affecting wave form as they approach and enter shallow water.
4. Two broad types of inshore waves are identified, constructive and destructive. Describe the differences and suggest reasons for their different form and frequency.
CW Date: 18th September 2017
Title:
Energy at the coast - Tides and currents.
14th Sept - No iCt so changed lesson to review/consolidate understanding of what the coastal system is... and then set question about extent to which the coastal system is affected by the opperation of other natural systems. Due to HI NL.
Following will need to be picked up NL:
Tides and Currents are also manifestations of energy at the coast. Tides result from the gravitational energy from the Moon and, to a lesser extent due to the greater distance from Earth, the Sun.
In the UK, there are two high and two low tides every day although they have an interval of somewhat over 6 hours so their actual time each day is slightly later.
The difference in level between the high and low tide is called the tidal range. This is also affected by the relative positions of the Sun and Moon to each other and the Earth.
The transition between high tide and falling tide… or Low tide and rising tide, involves a period of time at which there is little vertical variation in tide level (sometimes known as tidal slack). During this period, wave action is concentrated at a more limited range of heights against the shore. It is here that we often find specific features of erosion such as wave cut notches.
Where tidal range is low, wave activity is also concentrated more in a narrow band at the shore, increasing the effectiveness of erosion and formation of coastal features.
In contrast, where there is a high tidal range, waves will only break at a specific level on the beach for a relatively limited period of time. Thus, tidal range is an important factor in the vertical positioning of the effects of waves.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhVqL6ogAnQip4_EVEobm4N3TwKcYby8OuVBh4L79Z1qoMqr6P1zKBCLyCzC09B9a3eL89bIdEzmmdQsDexj2k0PPhR76idHlitRHGvIKxZ2C8SO9hfvjy7A5Bs-JkNjt7K_Cfp-SPPLDI/s320/Screen+Shot+2017-11-27+at+10.57.37.png)
Action:
Complete the following activities ready for next lesson (Wednesday 20th September 2017).
1. Explain the causation of Spring and Neap tides. Use diagrams to assist you.
2. Explain what a Rip Current is and how it contributes to the operation of sediment cells.
Home Learning:
1. Using labeled and annotated diagrams to assist you, explain how wave types and subsequent beach form can provide an example of negative feedback.
2. With reference to figure 2 on pp 106 of the text, attempt to show potential high energy and low-energy stretches of coastline on an outline map of the UK (download from the www). Write a reasoned commentary to support your map and ensure that you refer to both fetch and wind direction.
3. Complete the Kerboodle task assigned (Note that an error exists in the guidance - see my comments on Kerboodle). Use the guidance and write your answer on the appropriate Kerboodle slide. Once complete, press "submit". -
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Following to be "tweaked" and set as work for Wednesday 20th September. Class can work independently on this. All to complete prior to next lesson - 25th September 2017
CW Date: 20th September 2017
Title:
High and low energy coasts – pp109
Make Note/copy:
High-energy coasts are often rocky and tend to be facing the Atlantic Ocean where waves are more powerful for much of the year (Why?... Refer to HW above!).
Such high-energy locations are also where erosion tends to be greater than deposition… the two factors are, obviously connected given that energy is defined as "the ability to do work" and the work, in this case, is erosion.
Action:
1. List the types of coastal landforms that should be expected at high-energy coasts.
2. Explain your choices.
Make Note/copy:
Low-energy coasts, in contrast to High-energy coasts, tend to be “softer” or more rounded and less dramatic in appearance. They are typified by sandy and estuarine environments with less powerful waves or locations that are sheltered from the largest waves. Due to the calmer conditions, deposition generally exceeds the rate of erosion.
Action:
3. List the coastal landforms likely to be found in low-energy coastal environments and explain your selection.
Make Note/copy:
In addition to the orientation of the coast relative to powerful waves, high and low energy coastal environments may result from wave refraction.
Action:
4. What is meant by wave refraction?
5. Explain how/why waves are refracted diagrammatically.
6. How does wave refraction demonstrate the concept of negative feedback? Don't give up on this question... :)
CW Date: 25th September 2017
Mark Scheme - Kerboodle - HERE
Feedback from the assessment. - See above link
NB Notifications on SiMs
Title:
Sediment sources, cells and budgets. pp110 – 113
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Sediment sources:
Six sources of sediment are generally identified. Can you name them all?
(Highlight to view)
- Rivers
- Cliffs
- Longshore drift
- Wind
- Glaciers
- Offshore
Sediment sources:
· Rivers – In high rainfall environments where active river erosion occurs, this is frequently the main source of sediment at the coast. Material is deposited in river mouths and estuaries where waves, currents and tides will re-work it.
· Cliff erosion – Can be very important locally especially where exposed rocks are soft or unconsolidated. Glacial tills along the east coast (Holderness in Lincolnshire for example) are made of sand and clay which are quickly eroded (Up to 10m per year). In Cornwall, where coastal rocks are igneous granites, erosion is much slower and so coastal cliffs contribute much less to the sediments at the shore.
· Longshore drift – Removes sediment from one area of the coast (output) and adds it to another (input).
· Wind – In glacial or hot arid environments, wind-blown sediments can contribute to deposition at the coast. Where sufficient, fine material is available, dunes may form an accumulation (sink) of sediment or a potential source.
· Glaciers – Sediment trapped within glacial ice is released into the coastal environment when glaciers or ice sheets calve.
· Offshore – Waves, tides and currents can bring material into the littoral zone as well as remove it. The Flandrian Transgression at the end of the last ice age led to the transfer of considerable quantities of course sediment toward the current shoreline as the sea level rose. This process has formed the barrier beaches at Abbotsbury in Dorset (Chesil Bank) and Start Bay in Devon. Storm surges linked to tropical cyclones and tsunami can also push offshore sediment into the littoral zone (Florida?)
Globally, the majority of beach sediment is derived from rivers, streams and coastal erosion. The proportions from each source, however, vary considerably from place to place.
Sediment Cells:
Sediment cells are lengths of coast in which the movement of sediment is more or less contained. Physically these are usually defined at either end by distinct promontories or headlands.
In other words, a sediment cell includes all the inputs (sources), stores (sinks) and transfers (flows) of a discrete system. This is illustrated below (and pp 111 of the text):
Action:
1. Make a simple, but clear, copy (Ao3!).
2. Using the diagram you have drawn (and pp 110 to assist you) colour code the elements to identify the Inputs (sources), Transfers (flows) and Stores (sinks) of the sediment cell system.
Online test:
To complete (prior learning) - Shared form document (see gdocs folder) - will need to access ict.
In other words, a sediment cell includes all the inputs (sources), stores (sinks) and transfers (flows) of a discrete system. This is illustrated below (and pp 111 of the text):
Action:
1. Make a simple, but clear, copy (Ao3!).
2. Using the diagram you have drawn (and pp 110 to assist you) colour code the elements to identify the Inputs (sources), Transfers (flows) and Stores (sinks) of the sediment cell system.
Online test:
To complete (prior learning) - Shared form document (see gdocs folder) - will need to access ict.
CW Date: 26th September 2017
Title:
Sediment sources, cells and budgets. (Continued) pp110 – 113
Title:
Sediment sources, cells and budgets. (Continued) pp110 – 113
Entry Task:
Discuss... what do you understand by the term budget?
Can you describe/explain the idea in a geographical context?
Feedback from online test. Completed (highlight) - HERE
Sediment Budgets:
As in the case of financial budgets, sediment budgets comprise additions (inputs) and subtractions (outputs) which, if they can be quantified, allow assessment of the balance of inputs and outputs in a sediment cell. Ideally the sediment budget should be in balance so that a state of dynamic equilibrium is in place and the coast is neither eroding nor building through deposition.
Such dynamic equilibrium was previously referred to in relation to negative feedback in which changes in coastal form result in changes in the processes at work returning the coast to its former condition. This can be understood in terms of the action of constructive and destructive waves or with respect to the effect of wave refraction.
Such dynamic equilibrium was previously referred to in relation to negative feedback in which changes in coastal form result in changes in the processes at work returning the coast to its former condition. This can be understood in terms of the action of constructive and destructive waves or with respect to the effect of wave refraction.
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Action:
1. Describe and explain, in your own words, “sediment cells” (including inputs, transfers and stores)... If there is evident understanding this task can be adapted and put into the context of an example eg
Research task:
What is the historical evidence that Start Bay in Devon is a Sediment Cell?
2. Using the information on pp111 – 113 to assist you, complete the activities 1 to 5.
3. Discuss the view that sediment stores in sediment cells are permanent.
Above to complete in NL - 27th Sep 2017
Essay:
Using the BBC report - HERE, outline the arguments that Hallsands was a victim of a lack of systems understanding of the coast. (20 marks)
NB Geographical paper - place (including maps), illustrations and data... as well as well structured, fluent writing.
* Not actually set as I want class to revise.
CW Date: 28th September 2017
Title:
Weathering, mass movement and runoff
pp114 – 117
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Weathering, mass movement and runoff constitute examples of geomorphological processes… the earth-shaping processes.
Weathering
Weathering breaks down rocks in situ at or close to the ground surface. This group of processes clearly shows the flow of energy as most involve energy transfer from the sun (e.g. radiation or rainfall). Weathering also leads to the transfer of material and demonstrates the links between natural systems e.g. water cycle through freeze-thaw or carbon cycle through carbonation.
Weathering is active along coasts as there are frequently areas where rocks are exposed to the elements by constant removal or surface layers by erosion, weathering itself and by mass movement as a result of the action of the sea. By breaking rock down, weathering creates sediment that the sea can use to help erode the coast.
Note:
We can understand both types of feedback by referring to weathering processes in conjunction with the other debris-removing processes:
Positive feedback results when debris removal rates are faster than weathering and mass movement rates. The rapid removal of a potentially protective layer of material allows further weathering and mass movement and thus progressive changes.
Negative feedback results from conditions in which the rate of sediment removal is slower than those of weathering and mass movement. Here the accumulation of an apron of debris such as a scree slope, proffers protection for the cliff reducing the effectiveness of sub-aerial processes such as weathering.
Weathering is broadly divided into three types:
· Mechanical
· Biological
· Chemical
Action:
Using illustrations (either drawn, obtained from the www or a combination), describe and give examples of the three types of weathering (above).
Note: where www illustrations are used, ensure that you add your own labels and annotations to ensure that they are fully fit for the purpose you are employing them for).
Mass movement
Mass movement is the downhill movement of material under the influence of gravity aided (usually) by the presence of water. Mass movement at the coast is common and can range from very slow (such as soil creep) to astonishingly fast (rock falls and landslides). Combined with undercutting by marine erosion, the weight of rainwater accumulated in soils and weak geology are key causes of cliff collapse.
Mass movement transfers both energy and material. Sediments transferred form an important input to shoreline processes “arming” waves and currents with tools for erosion and also providing sediment to be deposited elsewhere along the coast. As such, the products of mass movement constitute inputs to cediment cells (Refer back to work on sediment cells).
Types of mass movement are divided into four types:
· Creep
· Flow
· Slide
· Fall
Each type of movement can be considered an output from one store (e.g. land) and input/transfer to another (e.g. beach or sea).
Key factors influencing the type of mass movement include:
· Slope angle
· Rock type
· Geological structure
· Vegetation cover
· Water content
Action:
1. Using the text (pages 116 and 117), complete a series of labeled and annotated sketches to describe the five types of mass movement outlined and for runoff and solifluction (you will have to design your own sketches to illustrate he latter two).
CW Date: 2nd October 2017
Title: Weathering, Mass Movement, Runoff (and Solifluction) - consolidation and application.
Complete the activities on the worksheet provided - HERE
CW Date: 4th October 2017
Title:
Revision - Prep. for "Transition Exams".
Jurassic Coast, Lyme Regis, 2014 – Case study of mass movement.
CW Date: 30th October 2017
Title:
Marine processes – erosion, transportation and deposition
(pp118 – 121)
Video Link - Dawlish 2014 - HERE
Coastal Erosion:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiOufXt4Mm-sbWzs37cbi6o726iHbYUuekXvpWjzDdoCYtIlNtoRQoZFMc-uMvd4jdcTyZHyaoECUqwba7Ea0ZrpJqOZBJHHAGjYjZs_XjN5xi7xV8XGd0eE_xORq7O0JYJ7mEiGoPr5CE/s320/Screen+Shot+2017-10-29+at+17.27.07.png)
In systems terms, erosion is a manifestation of the energy of the Sun, that is converted into waves by the power of the wind. There are a range of coastal processes of erosion. However, these will generally operate together.
Processes of Coastal Erosion.
- Hydraulic Action (Including cavitation)
- Corrasion
- Abrasion
- Solution (Corrasion)
- Wave quarrying
In addition, Attrition also takes place. This, however, does not lead directly to the erosion of the coast. Instead, it involves the wearing away of loose particles. As particles are moved by waves and currents, they collide and become both smaller and rounder/smoother.
Action:
1. Explain each of the processes of coastal erosion listed above (pp118/119). Use diagrams where appropriate to support your explanations.
2. The effectiveness of coastal erosion varies from place to place. Draw a spider diagram to illustrate the factors that influence coastal erosion (Ref. pp119/120)
3. What is the difference between rock lithology and structure?
Processes of Coastal Transportation.
Action:
4. Outline the role of Transportation in the coastal system.
5. The processes of transportation are:
- Traction
- Saltation
- Suspension
- Solution
Explain how each process operates.
6. Using your answers from activity 5 and with reference to the extract above, draw a diagram to describe the relationship between sediment size, velocity of moving water and the type of transportation. Add annotation/commentary to explain.
Home Learning:
You will be familiar with the process of Longshore Drift from your GCSE studies. Using this background and by carrying out additional research...
a. Briefly outline the conditions required for Longshore Drift to occur.
b. Geographical Skill:
Explain in detail, using a labelled and annotated diagram, how Longshore Drift operates.
c. What evidence might be found at the coast for the operation of LSD? Explain your answer.
For both the section on erosion processes and those on transport and deposition, worksheets have been produced. These include additional activities to those above. Links below:
Worksheet - Erosion Processes: HERE
Worksheet - Transport and deposition processes: HERE (To complete 1st Nov lesson + additional assignment - to prep. eg exam question/essay/extended writing).
Answer Guidance re. 3.5 textbook questions - HERE
CW Date: 6th November 2017
Title:
Feedback and Learning Checks.
Feedback:
Close/detailed observation and analytical application of knowledge and understanding.
e.g. Text task 1a - Processes responsible for erosion in this photograph?
Possible processes include:
- Wave quarrying
- Abrasion
- Attrition
- Hydraulic action (and cavitation)
- Corrasion
- Corrosion/solution
Which can be discounted?
Which may be having an effect and how do we know?
Which is most important?
Source: HERE
Behavior of Waves
Waves can bend when they encounter obstacles or changes on the sea floor.• Refraction involves bending. Wave refraction starts when wave base starts to interact with the sea bed and slow the waves down, causing them to bend toward shore. Refraction occurs when wave swells approach the beach at an angle (Figure 10-25).
• Diffraction involves spreading (or dispersion) of wave energy. Wave diffraction refers to various phenomena which occur when a wave encounters an obstacle or change in geometry of the seabed. For example waves are diffracted when they when they pass an island, or when they pass a point or other structure, such as a jetty at the mouth of a harbor (Figure 10-26).
• Reflection (bouncing) involves crashing into a solid surface (such as a seawall or cliff) and reflecting back to sea. Reflection can result in standing waves—waves that move back and forth (oscillate) in a vertical position waves strike an obstruction head-on and then are reflected backwards in the direction they came from.
H. Landforms and landscapes of coastal erosion – pp122 – 125
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjB_6hf3oMKg_1lQchIns6mTpXmdGz2LQeHS0PxX96v3Sm33jB8VXlM5wtQ24hh5yAt0R0Xx_AtmNhU7-J4xC23EwBC11KoZqiayrDoAWDCeSHQEJU3vwq_YSNWLptau8wNlYq_j0BFS0k/s640/Screen+Shot+2017-08-29+at+13.23.12.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgJNiZhXqZNLHX8j7o6LiltZKznSOcrMULphAcDkhVa6iRAPvJJpn8qQ8PKlliiXZTOIu138znCw8QU12KIy6zV27PgCaX5Z_9Hgz09lIwCUVXn1DpzQeAWjfkIOSXgrIJAsCX6e9psKaE/s640/Screen+Shot+2017-08-29+at+13.23.32.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhsvsOd1zBY4UJpbdXGrn5guxelBQRqfHxrsD_fpTIIL4sRPfNjtp6EPVCDWAfLeNqlDiOP7VwQdF8PVJ6s7bNeF2sXpjL3mVT3UsgXtLNa4_TzaU6UJNk2C1an8SNzoXbEF1fT9-Bh8IU/s640/Screen+Shot+2017-08-29+at+13.23.39.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjZUYZytcwHG_XffcrpuL85bD0TuUdjmna7mGOMhxEo_QA79Qd2RXJGcO_uU2OKNa1U9NqCUT_pFexzOKepzz50ikSMvBjEzb2sPuBCNU2c0BtnDewpQvLr37F0DK81-Q9ESwRy-gZYmgw/s640/Screen+Shot+2017-08-29+at+13.24.00.png)
The terms landscape and landform have specific and precise meanings. The landscape refers to the “bigger picture” or the surrounding area in its entirety. Landforms in contrast are individual elements of a landscape such as beaches, cliff, stack etc. It is necessary to be able to distinguish between the two and to consider landforms in their context of the wider landscape. This supports your interpretation of both and the development of an appreciation of the development of particular localities.
There is a further element to understanding environments that is not strongly referred to in the text. This is the pre-existing environmental conditions that may have left vestiges of previous and different processes, landforms and landscapes.
(ref. back to task 3 section F – Head filled valleys) NOTE... ref. to time and pre-existing conditions pp 130 re barrier beaches and sea level change.
Action (Completion for next lesson - 8th Nov 2017 - Presentations on Monday):
1. Describe the development of cliffs and wave-cut platforms.
2. How might a negative feedback loop operate during the development of an extensive wave-cut platform? Use diagrams to illustrate your answer.
Joe, Philip and James (Completed)
3. Explain why cliffs are in some places steep/vertical and tall and in others low and rounded/gently sloping (pp123).
4. Explain how weathering and mass movement, rock type and wave energy interact to determine the rate of cliff retreat.
Mo, Arun and Louis
5. Suggest how either sea level change or human activity can cause coastal erosion to increase or to decrease.
Zulaikah and Harlie (Harlie presented in Zulaikah's absence)
6. Using illustrations to assist, explain the influence of geological structure (lithology) on coastal morphology.
Helen (Completed)
CW Date: 8th November 2017
Landforms of Erosion and Erosional Environments - Feedback in teams
(colour coded tasks as above)
CW Date: 13th November 2017
Title:
Group Presentations (See colour coded assignments above).
Set assignment below (essay)
CW Date: 14th to 16th November 2017
Title:
Remaining Group Presentations + Working on Stretch Task and HL Assignment (Below)
Stretch and Challenge:
Complete activity on pp 125 using Google Maps/Earth Imagery.
HL:
Using the illustration provided, assess the influence of geological structure in the development of the coast in South Dorset.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgqwZfpqL1GGv9k8J631HpfgKHmA1FCxAuCdOEhVaCII-GmyoRSyMqjyvsg2X8ZoEp3zMQHIKKG4Mg1A1J5XhpXqp3ObPINpDtI1A6gt6T0cFD-gUQO-i5IgynKAAxqnfa7HM7k3iKEf6U/s320/Picture1.png)
In deconstruction the question... use "BUG"... ie
Box the command word
Underline the Theme, Focus and Specific Evidence required
Go back and re-view the question... make sure that you have not missed anything!
Understanding the Command Word...
Assess
Consider several options or arguments and weigh them up so as to come to a conclusion about their effectiveness or validity.
Source: HEREUsing the Image...?
Image...
CW Date: 20th November 2017
Title:
Landforms and landscapes of coastal deposition pp 126 – 132
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiClvZwGm8v3CcIaHAPFDcjw7WzzoDy6fqJoRtY-pjskZZkiTq6W54qmPKZVSn4dQAC7UtFzspjhuqdqJSkNFszoYZPKw9t0FbDkWCOEnIpX52TRfhEpRitvePp9Od29HiYsRyAWZRgJFw/s640/Screen+Shot+2017-08-29+at+13.26.18.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjf8t8YVB5i7Tyah2jM1vH4xQ0zskQ0hD1R5IV7mNQCsFC9ibPMYnBO7bQP1O77AcTJstL-mAU274_j1CCNfdeZhUCh4FBtvwzAOowmIGcrnvyKyznbKkmvACVqp2RlWN0FhO4doY5cyNE/s640/Screen+Shot+2017-08-29+at+13.26.40.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDiDgK_SsjK_V_0MRn7wLWbvM1eKMkX_gnmjngI2W5-vNOzo0cEuvFoGQSdYyYNqko55ZEI9veQLtRhiw6cwrlC-nJuuiIzN-xIcVMyj1U2JL5qXUjkjvPL_HIthNVN2aAewF3KIc5IrM/s640/Screen+Shot+2017-08-29+at+13.26.51.png)
How do beaches differ in summer and winter? Consider both human and physical features common to beaches in the UK.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiuKsofS3kpVhJmKMhlzDH3EjCnWqUpCFqIBjB10AsspGSzwqCcr4dcdMHxEKfUdj4FRSIIV2xPufbmRSkOPONNOpuoJ-i-j33PiiKZ7C_0v5wn1NbMrleRqsySm9b3AYqwokaQrnq0AsA/s200/Screen+Shot+2017-08-29+at+13.27.07.png)
Note to students:
It will be evident from the number of pages in the text devoted to depositional landscapes and landforms, that deposition is more complex and detailed at A level than at GCSE. While not neglecting erosional processes and landforms/landscapes, ensure that you devote sufficient time to develop detailed understanding of this section of the course.
Depositional Landscapes
Landscapes of coastal deposition fall into two broad categories:
· Those that are the result of low energy environments and
· Those that occur where there is greater energy available.
This idea presents a conundrum to begin with as we have already identified high-energy coasts with erosional landscapes.
Taking the South Dorset coast as an example and Chesil Bank specifically:
This locality is a high energy coast facing south and open to waves with a long fetch across the Atlantic Ocean (approaching diagonally up the English Channel from the SW).
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfrw9Cg7HLU4I-7DS31SXUhrUmseYyjP51-nXxjtC8QJklMjjDWbEEhArJik3fdza89Tvx-L0uJycjvet0IZwHMS0hnr815ZuwvbDi-LQ7DXHtVG81LJ5PMW0SwEn3cONOi9_KDwYhEp8/s640/Screen+Shot+2017-11-19+at+19.11.14.png)
This is reflected in the relatively course sediments present. Due to higher energy levels, finer material is removed leaving behind pebble sized sediment.
These materials originated in the English Channel where they were deposited by melt-water at the end of the Pleistocene Ice Age some 8,000 years BP (Store). As sea levels rose with the melting of ice on the land, waves and tides washed these sediments further onshore to their present position - Transfer (the rising sea level has been previously referenced – The Flandrian Transgression).
The sediments are, today, being reworked by long-shore drift that is largely from west toward the east.
(In systems terms… the deposits in the channel at the end of the ice age constituted the original store. This then provided an input to the coast as sea level rose. Today, long-shore drift is transferring the sediment – this illustrates the issue of time scale when interpreting events… what do we understand, for example, as “temporary”? I.e. in respect of the sediment store/s for Chesil Bank… does temporary refer to decades or millennia?).
In contrast to high-energy depositional environments such as Chesil Bank, sheltered bays provide low-energy environments where deposition of fine sediments by refracted waves create beaches of fine sediments such as sand. If there is sufficient sediment and a long enough period of exposure to drying wind, sediments can be moved to form dunes. Blown inland, such dunes can become colonized by halophytic vegetation and eventually, through the process of succession, develop into terrestrial ecosystems.
Examples of such lower energy environments on the South Dorset coast?
Note:
A key feature in distinguishing whether a depositional environment is relatively high or low energy is the size of sediments. Pebbles suggest high energy, sand suggest low energy.
CW Date: November 2017
Title:
Landforms of Deposition
Entry Activity:
Give possible factors contributing to the formation of beaches in bays.
(Consider more than one! - "factors").
Key Terms:
Swash Aligned
Drift Aligned
Landform
Deposition results when the waves no longer possess the energy to transport material. Once material ceases movement, it can accumulate to form a variety of landforms. The exact nature of the landform depends on the location and the precise processes at work.
Beaches
o Swash-aligned beaches
o Drift aligned beaches
o Beach forms
Whether a beach is Swash or Drift aligned depends on its orientation relative to incoming waves.
Make a simple sketch to illustrate the relevance of orientation.
· Spits, Tombolo etc as indep study and HL
CW Date: 6th December 2017
Title:
The Forms and Features of Beach
independent study as Parents Evening:
Link to assignment note - HERE (Set via Classroom)
Entry task:
Study the beaches illustrated below... what distinctive features can you identify (you do not need to be able to name each)?
Highlight to see...
![](https://i1.wp.com/www.alevelgeography.com/wp-content/uploads/2016/01/ridges-and-runnels-5.jpg?fit=1020%2C680)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgL0cMQPDv4BYjKmuEQ6D7YHPKvtHD4xo9ApeURWSY9RZ3NqAU46gaF3XvrEOqXzLsRUenusM2m5kduTVF3nqb1_WlcRXUiCo-gOw2UwrH2y0gHC3TrhYzt6kAEXICo7ED5m7-WfnuJ6to/s320/Screen+Shot+2017-11-27+at+11.01.00.png)
Berms, storm beach and cusps
Runnels
Cusps cut into berm
Beaches, as previously noted, are dynamic and ever-changing features. Their specific form, in long profile, often includes a range of features that we overlook including berms, bars, cusps and runnels.
Berms and bars
Form where there are changes in the capacity of waves to move material across the beach, for example, at or behind the breaker line.
Turbulence of the breakers entrain material that is then redeposited where conditions are calmer to form an elevated linear feature.
When wading across a sandy beach, such features will be noticed as a location offshore where water depth decreases noticeably.
Storm Beaches
Storm beaches show the position of the highest tides/wave action during storms. They result from accumulation of courser material transported by the swash phase, but which is unable to be returned down-slope due to the weakened backwash phase. Because these are deposited during storms or at especially high tides, they are located toward the back of beaches.
Berms (and storm beaches) can be excavated and collapse due to destructive wave quarrying which can re-deposit material further down the beach where conditions are somewhat less energetic. This process can also contribute to bar formation (see above).
Note that this cross profile also shows how the beach can be divided into four zones... the Backshore, foreshore, Nearshore and Offshore zones.
Beach Cusps
How are Beach Cusps Formed?
Beach cusps are more likely to form on beaches that have coarse material like pebbles. Although wave action causes the formation of beach cusps, the process is not fully understood. One theory suggests the frequency of wave patterns may help to create them.
When incoming waves meet a flow of water returning seaward from a previous wave, this generates waves that move toward the left and right, parallel to the shoreline (Edge Waves). They can move in opposite directions. When they collide, this can increase the height of an incoming wave. The frequency of these wave patterns may produce the arcs and beach cusps.
Flow patterns in Cusps: HERE
From the video, you will appreciate that there remains a question as to whether the edge waves form the cusps or, in fact, the edge waves are a product of the changes in slope direction resulting from the cusps.
Runnels
Runnels, and associated ridges, form parallel to the shore line in the foreshore zone. Ridges are areas of the foreshore that are raised above the adjacent shore which dips into a runnel.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiGwnKx1FVEFsbP4_KI8QGFPmRB1inQIK3bLyeslpTIyrt6_U-XGUHDSG9Wgg3EGQAQ7H-m0ROosULEK1-sl6BFnBeP1yuTBHWlmTQMganeW3KAHhFemLONqyrMGwRVv_BPjbvf_nwcqf0/s400/Screen+Shot+2017-11-27+at+12.02.36.png)
Runnels form channels parallel to the shore line. They may be dissected by channels at right angles which drain water to the sea.
The development of runnels may be associated with Bar and Berm development as these latter formations create a barrier to the drainage of water down the beach back to the sea. Berms and Bars can redirect drainage along the shore instead of down the beach.
Notes already assigned for completion:
Title:
Estuarine Mudflats and saltmarshes
Complete the activities on pp132/133 (Including the “stretch” activities…).
All should be finished by 11th December 2017
CW Date: 11th December 2017
Title:
Sea Level Change
pp 134-139
Entry Activity:
Study the image... what does it show?
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgCeDOZcF3EDU0QpZR6ajcPOqtoIrBxgga7NkJjb3HzAGMPQgj953u7Rs_oSBlB_Lq_gI-Z2muua3shSZUMbl-iucPL8GK1Sr5xExeyIvr2vcB1nHrIpWulvTqp_n5ejAHF8YEJCH3CI08/s640/Screen+Shot+2017-12-10+at+16.36.58.png)
What has led to the formation of the features you have identified?
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpeowuSZiQaVp_cbCA2sTYEzgmXL9qwJJeKUHUhN3rzLFvMYNM-rdkTyAgVzcuxGgOJJJJXrwuF3PRNcLRSljJpOEkEdY_wMdW0MmUf4K3Z6jlQc5GhXxs_fWpFcBpEjjaDH34YuYBvIw/s640/Screen+Shot+2017-08-29+at+13.28.52.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKXxJ17qbjYOv8ozl5ACZ0fmIPY1UlOeqEdkOpuAkdfdO7ztbMVEmxcBfGIujf7dqI67efX_TtErIX0lFd57MMH-C12M5cmBgqlxaYHc0Lt3_6v-mN84KxmaJk9gUkU4m7Ck_jBH5U6Vw/s640/Screen+Shot+2017-08-29+at+13.29.01.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHq6xvFzKwPij6NHlLAiu4fr3wwC4VBne4jQu4dwRnh3mkalNGArn3vyWHSqkJQkNS3brwnNAXtgvHCiNx4MbJBssmKRwxAtcWHJJAyo0L0e4ywG3RFQemdsmVJ5kdXUtadzrMaoqbb30/s640/Screen+Shot+2017-08-29+at+13.29.11.png)
Why are seal levels changing today?
How much are they changing by?
What makes Tarawa Atol so vulnerable to sea level rise? - Google Earth View: Here
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhxyp4SLEzkjlG0OlZUxQKNuOZKLBERTr7LtdqYlcig_2_1keK7agF3Cj9K1_GgVzfIQLRB8BOKjwcPapd9z1z4f0kMjsvKEq-WGgvgUJQsbWyn8eoNUQR1feUsgyDKz-Io2Jrrm_r3__U/s640/Screen+Shot+2017-12-10+at+16.54.32.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgLRI78QVWQXBs73n4NgXVKEFkot-TMT7G7PVG4a4fQEhXzzFj-KS0r8smHK1GnJJ35RnoUn2ez_nLMUyxK6bQi8XTc6_pInAfGVdMPPiOUUv8GO0BVpQeMM_-Tk7q4jGsl6WRaTpXXHIc/s640/Screen+Shot+2017-12-10+at+16.56.03.png)
Location is approx 3000km SE of Hawaii in the Pacific Ocean.
Sea Level is the boundary between land and sea as defined by the highest level reached by the sea during storms or Spring Tides and the low tide level. This tidal range is usually just a few metres and is where the action of the sea is focussed day to day.
Over the geological past, however, the sea level has varied enormously. During the several glacial periods of the Quarternary period sea levels dropped only to rise again during the warmer interglacials.
Sea level changes in two ways:
Eustatic change when the sea level itself changes and...
Isostatic - when the level of the land changes relative to the sea.
Eustatic change is a global phenomenon. For example, during glacials, vast quantities of water are stored as ice and snow on land causing the ocean levels to fall.As ice and snow melts with the onset of interglacials, water is returned to the oceans and levels rise again.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiXASLOMn77upmbOIbinrv8tVmauhBR_OiWWPPCWk0vc5O1ilh-dwyBXz3wFWycbvrImjzz7pmj48q6dO5SgVxytTKR7P6uiXLdHryPxzWkanMr-K-7-agJdyJ5Ed6K9NyPemCq7NuB2Sg/s640/Screen+Shot+2017-12-10+at+17.21.53.png)
Isostatic change, in contrast to eustatic, is a localised phenomenon resulting from the application or removal of overburden on the land. This overburden is typically ice during glacial periods which pushes the land down into the mantle below. This isostatic subsidence is replaced by isostatic rebound once the ice melts during interglacials.
Isostatic rebound (or recovery) is responsible for the features of raised beaches and relict cliff lines on the image seen at the beginning of this section... Tarawa, however, is threatened by Eustatic sea level rise.
Action:
1. Explain the synoptic links between sea level change and the water/carbon cycles.
2. Describe the sea level changes affecting the UK since the end of the last glacial period.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgXsrrsBkPMjCkbTzrIqbVckCOdC8if2I2CvjIxI_UPcVdLq0Zczyiwt3KEc-G1F0eTwi6PI-Oczcn8qAccB16YFClNb5EOfjLVqEk4p9WO_NTvngsCLTe52MqRaV-qFCyZjV7OT1qds_k/s320/Screen+Shot+2017-12-10+at+17.41.24.png)
3. Compare the two photographs of Banda Aceh in Sumatra prior to and after the Earthquake of 2004. On the top image, mark the areas that have been "lost".
Source - HERE
4. With reference to examples (research!), outline how tectonic activity causes isostatic change.
5. What are emergent coastlines and submergent coastlines? Describe the landforms that distinguish each.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjVe6XMXnZA5JpBjdo0MIwc8ceEe3hB8YnwNCJvh-fLn2pTfej2Ijawr5nULTIWKseePw7gNI5cEsdOfwAaUMy6uWBURk0gsGXc25PjokfhQoYpKdJlIm1lddzAVnAt7_pCn9vfBQTeel0/s640/Screen+Shot+2017-12-10+at+17.59.05.png)
Activities from the text pp 139
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrEU85CC4yfZALM3e6sLtDl4OTbeDxyjIuzPM8mL7bXtzFJ8CA7N8zrelTyIN6zoMj12lFZwIFJTu6dGkCT-VKOCuWj5tfE_17nRhuB_wKf4MIcHiWpS4fUUsTqUpEkGGoUuDcfbMUTAw/s640/Screen+Shot+2017-12-10+at+18.05.00.png)
Coastal Bevel
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjn-0JI9FKO79VDo5cC69KpRQBPeO3zM7YjA-wy1sjLcoaxTDAQ13lFyxU8pZHe0jS7sDGAKBk7DIRAcbSrqAWYyBJB8BJtC45ieNQ1jOLuAa8125fRxZbTnLM4rlHNhFed9FcuX3Haun4/s640/Screen+Shot+2017-12-10+at+18.16.04.png)
(Not same as slope over wall cliff in terms of formative process... although look exactly the same!)
Sustainable integrated management approaches.
In more recent years, coastal management has begun to adopt an approach that is more in keeping with a systems understanding of coastal environments. Although similar to soft engineering principles of working with nature and having long term sustainability, the new approach also aim to be more holistic and to take into account processes over larger areas of the coast rather than focusing on the needs at a specific, smaller and more localised stretch of coast. This, of course, allows principles of management based around sediment cells to be utilised. Such a philosophy underlies the Shoreline Management Plan (SMP).
The shoreline management plan has been developed to incorporate the views of all those involved in the development, management and use of the coast. This process is termed Integrated Coastal Zone Management and aim to establish sustainable levels of economic and social activity; resolve environmental, social and economic challenges and conflicts; and to protect the coastal environment.
Action:
1. Explain the benefits of ICZM. Include references to coastal systems theory as appropriate and ensure that you demonstrate understanding of the term “holistic”.
Ref:
Pp143 of the course text
http://ec.europa.eu/environment/iczm/index_en.htm
North Solent Shoreline Management Plan: HERE
Based on your reading of the above, how is the management of the North Solent Coastal region justified?
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivpu3_DLHw3zsceeTB6nQYHMzMJXxCzBS6TECKUZ26lHIE8_AWn6oQukMAL7k3wurzjjfbcEq0zpRXO6VXMhWdcK0wXnba5b7MyxPdFoPaBiv4ZI-jwcbSVRVclKjW0Wj6rwAt3cDc9iw/s640/Screen+Shot+2017-08-29+at+13.29.23.png)
Evidence exists for long term sea level change in landscapes that include coastal/marine features that have been exposed of left above the current sea level (indicating a fall in the level of the sea) and landscapes where terrestrial or fluvial features and landscapes have been flooded (as sea level rises). Respectively, these landscapes are termed emergent or submergent and may result from two types of relative sea level change.
Sea level is not universally rising or falling. There are, instead, local/regional variations and places where the relative level is rising or where it is falling.
Is sea level the same across the oceans? - https://oceanservice.noaa.gov/facts/globalsl.html
The causes of sea level change (slc) fall into two categories:
· Eustatic change - When the surface level of the ocean rises or falls. This is generally associated with alterations in the global climate that cause differences in precipitation and the stores of ice on the land. During glacial periods, for example, precipitation falls as snow onto land instead of rain. Over time, this may form huge ice sheets that store water on the land instead of allowing it to flow into the oceans. Consequently, sea level falls. As climate ameliorates, the stored water on land melts and returns to the oceans raising their levels again.
· Isostatic change – This too is often linked to the accumulation of ice on land. The sheer weight of ice sheets that may be several kilometers thick, presses land downward. As ice melts in warming climates, the land slowly rises again. This is known as isostatic readjustment or recovery.
Ref. - http://thebritishgeographer.weebly.com/sea-level-change.html
Note:
Eustatic change is when the sea level changes due to an alteration in the volume of water in the oceans or, alternatively, a change in the shape of an ocean basin and hence a change in the amount of water the sea can hold. Eustatic change is always a global effect.
Isostatic uplift is the process by which land rises relative to the sea due due to some localised process such as the melting of an ice overburden or tectonic activity.
Isostasy. ... When a certain area of Earth's crust reaches the state of isostasy, it is said to be in isostatic equilibrium. Isostasy does not upset equilibrium but instead restores it (a negative feedback).
From the above, it should be understood that isostatic and eustatic are terms associated with changes of differing scale and that they may be the result of processes other than the accumulation or loss of ice from the land.
Through an appreciation of eustatic and isostatic changes, we can recognize the links between coastal sea level change and the water and carbon cycles. For example, alterations in the balance of stores in the water cycle can lead to changes and, especially today, we are able to understand the impact of changes in the proportion of Co2 in the atmosphere on global climate and, in turn on the amount of ice on the land which is in turn related to both eustatic and isostatic slc.
Action:
1. Referring to page 135 (and other sources eg the www), describe the isostatic changes affecting the UK today. Include a copy of a similar map to that in figure 2 pp 135).
Sea Level change due to Tectonic activity.
Tectonic activity directly impacts on coasts globally due to:
· Mountain building (Orogenesis) and land uplift at destructive and collision plate margins that have resulted in relative fall in sea level in some locations.
· Local titling of land at destructive margins, for example, some ancient Mediterranean ports have been submerged and others have been stranded above the current sea level.
The 2004 Indian Ocean earthquake measuring about 9 on the Richter Scale killed over 275,000 people. The closest inhabited land was the island of Sumatra and this was hit by the resultant tsunami within 15minutes. The wave reached up to 15m high and devastated the city of Banda Aceh as well as other areas of the island. The situation was exacerbated by the tectonically induced sinking of the earth’s crust around Banda leading to the permanent flooding of large parts of the city.
The earthquake was caused by slippage along about 1600km of fault between the Indian and Burma plates. The seabed rose several metres, displacing an estimated 30km3 of water as well as triggering the tsunami. This elevation of the sea bed reduced the Indian Ocean’s capacity producing a permanent rise in sea level of an estimated 0.1mm.
Tectonic activity generates a huge amount of energy that is transferred by waves to the coast. The devastation and erosion of the coastline caused by the 2004 tsunami pays testament to the immense amount of energy harnessed by the waves. These one-off energy flows are very significant in causing coastal change and they exemplify the principle that most change in natural systems involves high-magnitude, low-frequency events.
Landforms caused by changing sea level.
Changing sea levels affect the shape of coastlines and form new landforms. Falling levels expose land formerly covered by the sea, creating emergent coastlines. A rise in sea level floods the coast and creates a submergent coastline.
Emergent coastal landforms
Raised beaches and associated features
Submergent coastal landforms
Rias and Fjords
Dalmatian coasts
Contemporary sea level change.
According the IPCC, sea levels stabilized about 3000 years BP and have only recently begun to change again. From the end of the 1800s there has been an average global sea level rise of approximately 1.7mm per year. Between 1993 and 2010, however, this increased to about 3.2mm p.a. The IPCC estimate that, by 2100, sea levels could rise by between 30cm and 100cm from current levels. However, there is likely to be considerable variation from place to place.
Current sea level change is largely though to be the product of thermal expansion plus the effect of melting ice from land stores such as Greenland, Antarctica and upland glaciers resulting from global warming (average increase of 0.85oC 1880 to 2010). These changes clearly show the link between coastal and glacial systems, water and carbon cycles through rises in atmospheric Co2 leading to an enhanced greenhouse effect that in turn changes global stores of water leading to greater volumes in the oceans and sea level rise.
Action:
2. Summarise the problems facing Kiribati due to changes in sea level.
3. Research, using the internet, how well Kiribati is coping with the effects of climate change.
4. Complete the activities 1 to 5 on pp139
I. Coastal Management – pp140 – 143
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8OJnIeozZYpu2Z50RtuPeZbVQS6RWANMltw_c1HYDhDZB-IdqvqK0b6W4Z8i8Ux6z3bP28fPxDs6Wy83ITk9pMVpIL5aLdCMu8GSI-hgsMwlklgZ1bUHYD8_vkZBgV-Q1Tk75H17XfSc/s640/Screen+Shot+2017-08-29+at+13.30.54.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9rQmElHw_GEY7rV9mvBlBsnfp8Qo3Gg9ZsT_34vrPomx4DDDkmLl6Hmu1rbtnGAENZy12bfdN78Lu0Rj5TqUqpm_Q-tkbkFnfTAp0llqTl_r-2yFKvdZOmKUPKHP8e8i7ItirPYR_Fmc/s640/Screen+Shot+2017-08-29+at+13.31.09.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEir7toIBULP2lfv8fTo_EtfjVD5j19IEQI62c1mrYIBZW7iD89Bls8f7ZGD7MuHOpXca9ICR-9i7a9mNFA-OvdsN3ek5Sihncsg92z7j_e-v0IETVDky3JeQRxeZkPJmqVpD1NVNTlWZkI/s640/Screen+Shot+2017-08-29+at+13.31.16.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiZ1aXDV2V3pbT6-ENY3bjvYPWrahhx49jS7dFJFKKax1xUiNriy-VnmS1PQ2HHmQ_5VmcLF0awKvp99j-_hhUA5Q4ylQ1U9750oB90x7V5tVThKMDZ3PC-dpWrFK0YMumlfCSUy6VGuns/s640/Screen+Shot+2017-08-29+at+13.31.28.png)
It is estimated that some 50% of the world’s population live within 60km of the coast and 75% of all large cities are on the coast. The coast is also under continued and considerable pressure from further development. The combination of these factors means that the coast is threatened by environmental damage and habitat destruction. Globally important ecosystems such as mangroves and coral reefs are being lost and damaged and the populations living in these areas are increasingly at risk from the effects of coastal erosion and flooding. Such risks are likely to grow as global climate warms and sea levels rise.
Action:
Explain how sea level rise increases the risks of erosion.
Traditionally, coastal management has been divided into Hard and Soft engineering approaches. These methods can temporarily prevent erosion, but they are expensive and this cost may be controversial especially at times of economic slowdown. Hard engineering and soft engineering are frequently used together although there has been increased interest in “soft” methods as these tend to be less expensive and less environmentally obtrusive and damaging.
Action:
Make notes and illustrations to outline the methods (listed below) of coastal management plus their relative advantages, disadvantages and costs.
Hard:
· Groynes
· Sea Walls
· Rip rap (rock armour)
· Revetments
· Breakwaters
Soft:
· Beach nourishment
· Cliff slope grading and drainage
· Dune stabilisation
· Marsh creation
Sustainable integrated management approaches.
In more recent years, coastal management has begun to adopt an approach that is more in keeping with a systems understanding of coastal environments. Although similar to soft engineering principles of working with nature and having long term sustainability, the new approache also aim to be more holistic and to take into account processes over larger areas of the coast rather than focusing on the needs at a specific, smaller and more localised stretch of coast. This, of course, allows principles of management based around sediment cells to be utilised. Such a philosophy underlies the Shoreline Management Plan (SMP).
The shoreline management plan has been developed to incorporate the views of all those involved in the development, management and use of the coast. This process is termed Intergrated Coastal Zone Management and aim to establish sustainable levels of economic and social activity; resolve environmental, social and economic challenges and conflicts; and to protect the coastal environment.
Action:
1. Explain the benefits of ICZM. Include references to coastal systems theory as appropriate and ensure that you demonstrate understanding of the term “holistic”.
Ref:
Pp143 of the course text
http://ec.europa.eu/environment/iczm/index_en.htm
2. Complete the activities on pp 142 of the text.
3. Complete the “stretch” activity on pp 143 of the text.
J. Case Study – Coastal Processes on The Holderness Coast – pp144 – 147
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgK2DoJP2uG_SfMhVeR9hI6YjaVYnDUI_1avj9ZyJSr_7QHGRJtVya7yb1Af6SfxBDKGY2K1U7h_SEpTWwUaJfcJ3NIg59aaXJb35Py_UthSRo_d5cEesJG4w2j_1jPjRE_BYqV6cuxukw/s640/Screen+Shot+2017-08-29+at+13.34.28.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjlOXGjGzey5X8ukuJq5amAP4cLomxtm1JcN0J6oymJCa3DEEnqncc7Ih8ziCwtQnZqMh5M_c8uuq3IjgVQ2pnOQsBN2Kg5wTSlqUG5pD0uQz5ozdNX53_DlsdzNkgf3H_L4uYYWpYWKaQ/s640/Screen+Shot+2017-08-29+at+13.34.41.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgVQ5E9nDHwLmLyw9sBABbE4oA_A8vDgZQlY815rs0nKLfw2f97PkDZWawb3sll0BwIu0uA3PqLw-Hgw1H7SkF8ANO80QMpCACse5zbuJPaUoPAE01Oh1T-8CR1WTq4X2Fbg72e1YXfGEo/s640/Screen+Shot+2017-08-29+at+13.34.52.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhwbJqWFGTn4bssxMYEv8Epnkc22HPQQKDTWNue2N9ourYSOffG03UtWEyUhuTeyWYnV3uiLfALR-2MqIosu3pDlw38jSb6jn3q1w2gfoBS7l4ljFfiB7OmNPwK0APVchoTTfC0dy4jHLY/s640/Screen+Shot+2017-08-29+at+13.35.02.png)
Using the material in the course text and additional research, study the coastal processes on the Holderness coast.
K. Case Study – Risk and Opportunity in Odisha, India – pp148 – 153
Actions:
1. Review in depth the case study of Odisha (pp148 – 153) in the text, making appropriate notes to support your learning.
2. In class, complete activity 1, 2, 3 and 4.
3. HW: Activities 5 and 6 (For hand in and assessment)
4. In class: Activity 7 (Guided map interpretation and description)
5. Plan an answer to the following question (Q13/pp 155) using the Odisha case study:
“Much of the handwringing over sea level rise is precisely because so much of the world’s population lives near the ocean”.
For a coastline you have studied, analyse the respective roles of resilience, mitigation and adaptation in maintaining coastal communities. 20 Marks
L. Practice questions – pp154 – 155
Completion of the practice questions in class under exam conditions (ish).
The development of runnels may be associated with Bar and Berm development as these latter formations create a barrier to the drainage of water down the beach back to the sea. Berms and Bars can redirect drainage along the shore instead of down the beach.
Notes already assigned for completion:
Title:
Estuarine Mudflats and saltmarshes
Complete the activities on pp132/133 (Including the “stretch” activities…).
All should be finished by 11th December 2017
CW Date: 11th December 2017
Title:
Sea Level Change
pp 134-139
Entry Activity:
Study the image... what does it show?
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgCeDOZcF3EDU0QpZR6ajcPOqtoIrBxgga7NkJjb3HzAGMPQgj953u7Rs_oSBlB_Lq_gI-Z2muua3shSZUMbl-iucPL8GK1Sr5xExeyIvr2vcB1nHrIpWulvTqp_n5ejAHF8YEJCH3CI08/s640/Screen+Shot+2017-12-10+at+16.36.58.png)
What has led to the formation of the features you have identified?
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpeowuSZiQaVp_cbCA2sTYEzgmXL9qwJJeKUHUhN3rzLFvMYNM-rdkTyAgVzcuxGgOJJJJXrwuF3PRNcLRSljJpOEkEdY_wMdW0MmUf4K3Z6jlQc5GhXxs_fWpFcBpEjjaDH34YuYBvIw/s640/Screen+Shot+2017-08-29+at+13.28.52.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKXxJ17qbjYOv8ozl5ACZ0fmIPY1UlOeqEdkOpuAkdfdO7ztbMVEmxcBfGIujf7dqI67efX_TtErIX0lFd57MMH-C12M5cmBgqlxaYHc0Lt3_6v-mN84KxmaJk9gUkU4m7Ck_jBH5U6Vw/s640/Screen+Shot+2017-08-29+at+13.29.01.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHq6xvFzKwPij6NHlLAiu4fr3wwC4VBne4jQu4dwRnh3mkalNGArn3vyWHSqkJQkNS3brwnNAXtgvHCiNx4MbJBssmKRwxAtcWHJJAyo0L0e4ywG3RFQemdsmVJ5kdXUtadzrMaoqbb30/s640/Screen+Shot+2017-08-29+at+13.29.11.png)
Why are seal levels changing today?
How much are they changing by?
What makes Tarawa Atol so vulnerable to sea level rise? - Google Earth View: Here
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhxyp4SLEzkjlG0OlZUxQKNuOZKLBERTr7LtdqYlcig_2_1keK7agF3Cj9K1_GgVzfIQLRB8BOKjwcPapd9z1z4f0kMjsvKEq-WGgvgUJQsbWyn8eoNUQR1feUsgyDKz-Io2Jrrm_r3__U/s640/Screen+Shot+2017-12-10+at+16.54.32.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgLRI78QVWQXBs73n4NgXVKEFkot-TMT7G7PVG4a4fQEhXzzFj-KS0r8smHK1GnJJ35RnoUn2ez_nLMUyxK6bQi8XTc6_pInAfGVdMPPiOUUv8GO0BVpQeMM_-Tk7q4jGsl6WRaTpXXHIc/s640/Screen+Shot+2017-12-10+at+16.56.03.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgDANG8N73KPcX-E3Dr6JljkN46-LSGhhtOSp907-Q0p-zapSxMUqwh31rej0vwOXN3LEDD8hdP8j6c-CFm9aSHIh_X8g_BKizpc6aCPb-UzgbN4UA51LBtktrHzQTrxAeKjYHV_7aFdRk/s400/Screen+Shot+2017-12-10+at+16.57.38.png)
Sea Level is the boundary between land and sea as defined by the highest level reached by the sea during storms or Spring Tides and the low tide level. This tidal range is usually just a few metres and is where the action of the sea is focussed day to day.
Over the geological past, however, the sea level has varied enormously. During the several glacial periods of the Quarternary period sea levels dropped only to rise again during the warmer interglacials.
Sea level changes in two ways:
Eustatic change when the sea level itself changes and...
Isostatic - when the level of the land changes relative to the sea.
Eustatic change is a global phenomenon. For example, during glacials, vast quantities of water are stored as ice and snow on land causing the ocean levels to fall.As ice and snow melts with the onset of interglacials, water is returned to the oceans and levels rise again.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiXASLOMn77upmbOIbinrv8tVmauhBR_OiWWPPCWk0vc5O1ilh-dwyBXz3wFWycbvrImjzz7pmj48q6dO5SgVxytTKR7P6uiXLdHryPxzWkanMr-K-7-agJdyJ5Ed6K9NyPemCq7NuB2Sg/s640/Screen+Shot+2017-12-10+at+17.21.53.png)
Isostatic change, in contrast to eustatic, is a localised phenomenon resulting from the application or removal of overburden on the land. This overburden is typically ice during glacial periods which pushes the land down into the mantle below. This isostatic subsidence is replaced by isostatic rebound once the ice melts during interglacials.
Isostatic rebound (or recovery) is responsible for the features of raised beaches and relict cliff lines on the image seen at the beginning of this section... Tarawa, however, is threatened by Eustatic sea level rise.
Action:
1. Explain the synoptic links between sea level change and the water/carbon cycles.
2. Describe the sea level changes affecting the UK since the end of the last glacial period.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgXsrrsBkPMjCkbTzrIqbVckCOdC8if2I2CvjIxI_UPcVdLq0Zczyiwt3KEc-G1F0eTwi6PI-Oczcn8qAccB16YFClNb5EOfjLVqEk4p9WO_NTvngsCLTe52MqRaV-qFCyZjV7OT1qds_k/s320/Screen+Shot+2017-12-10+at+17.41.24.png)
3. Compare the two photographs of Banda Aceh in Sumatra prior to and after the Earthquake of 2004. On the top image, mark the areas that have been "lost".
Source - HERE
4. With reference to examples (research!), outline how tectonic activity causes isostatic change.
5. What are emergent coastlines and submergent coastlines? Describe the landforms that distinguish each.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjVe6XMXnZA5JpBjdo0MIwc8ceEe3hB8YnwNCJvh-fLn2pTfej2Ijawr5nULTIWKseePw7gNI5cEsdOfwAaUMy6uWBURk0gsGXc25PjokfhQoYpKdJlIm1lddzAVnAt7_pCn9vfBQTeel0/s640/Screen+Shot+2017-12-10+at+17.59.05.png)
Activities from the text pp 139
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrEU85CC4yfZALM3e6sLtDl4OTbeDxyjIuzPM8mL7bXtzFJ8CA7N8zrelTyIN6zoMj12lFZwIFJTu6dGkCT-VKOCuWj5tfE_17nRhuB_wKf4MIcHiWpS4fUUsTqUpEkGGoUuDcfbMUTAw/s640/Screen+Shot+2017-12-10+at+18.05.00.png)
Coastal Bevel
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjn-0JI9FKO79VDo5cC69KpRQBPeO3zM7YjA-wy1sjLcoaxTDAQ13lFyxU8pZHe0jS7sDGAKBk7DIRAcbSrqAWYyBJB8BJtC45ieNQ1jOLuAa8125fRxZbTnLM4rlHNhFed9FcuX3Haun4/s640/Screen+Shot+2017-12-10+at+18.16.04.png)
(Not same as slope over wall cliff in terms of formative process... although look exactly the same!)
Sustainable integrated management approaches.
In more recent years, coastal management has begun to adopt an approach that is more in keeping with a systems understanding of coastal environments. Although similar to soft engineering principles of working with nature and having long term sustainability, the new approach also aim to be more holistic and to take into account processes over larger areas of the coast rather than focusing on the needs at a specific, smaller and more localised stretch of coast. This, of course, allows principles of management based around sediment cells to be utilised. Such a philosophy underlies the Shoreline Management Plan (SMP).
The shoreline management plan has been developed to incorporate the views of all those involved in the development, management and use of the coast. This process is termed Integrated Coastal Zone Management and aim to establish sustainable levels of economic and social activity; resolve environmental, social and economic challenges and conflicts; and to protect the coastal environment.
Action:
1. Explain the benefits of ICZM. Include references to coastal systems theory as appropriate and ensure that you demonstrate understanding of the term “holistic”.
Ref:
Pp143 of the course text
http://ec.europa.eu/environment/iczm/index_en.htm
North Solent Shoreline Management Plan: HERE
Based on your reading of the above, how is the management of the North Solent Coastal region justified?
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivpu3_DLHw3zsceeTB6nQYHMzMJXxCzBS6TECKUZ26lHIE8_AWn6oQukMAL7k3wurzjjfbcEq0zpRXO6VXMhWdcK0wXnba5b7MyxPdFoPaBiv4ZI-jwcbSVRVclKjW0Wj6rwAt3cDc9iw/s640/Screen+Shot+2017-08-29+at+13.29.23.png)
Evidence exists for long term sea level change in landscapes that include coastal/marine features that have been exposed of left above the current sea level (indicating a fall in the level of the sea) and landscapes where terrestrial or fluvial features and landscapes have been flooded (as sea level rises). Respectively, these landscapes are termed emergent or submergent and may result from two types of relative sea level change.
Sea level is not universally rising or falling. There are, instead, local/regional variations and places where the relative level is rising or where it is falling.
Is sea level the same across the oceans? - https://oceanservice.noaa.gov/facts/globalsl.html
The causes of sea level change (slc) fall into two categories:
· Eustatic change - When the surface level of the ocean rises or falls. This is generally associated with alterations in the global climate that cause differences in precipitation and the stores of ice on the land. During glacial periods, for example, precipitation falls as snow onto land instead of rain. Over time, this may form huge ice sheets that store water on the land instead of allowing it to flow into the oceans. Consequently, sea level falls. As climate ameliorates, the stored water on land melts and returns to the oceans raising their levels again.
· Isostatic change – This too is often linked to the accumulation of ice on land. The sheer weight of ice sheets that may be several kilometers thick, presses land downward. As ice melts in warming climates, the land slowly rises again. This is known as isostatic readjustment or recovery.
Ref. - http://thebritishgeographer.weebly.com/sea-level-change.html
Note:
Eustatic change is when the sea level changes due to an alteration in the volume of water in the oceans or, alternatively, a change in the shape of an ocean basin and hence a change in the amount of water the sea can hold. Eustatic change is always a global effect.
Isostatic uplift is the process by which land rises relative to the sea due due to some localised process such as the melting of an ice overburden or tectonic activity.
Isostasy. ... When a certain area of Earth's crust reaches the state of isostasy, it is said to be in isostatic equilibrium. Isostasy does not upset equilibrium but instead restores it (a negative feedback).
From the above, it should be understood that isostatic and eustatic are terms associated with changes of differing scale and that they may be the result of processes other than the accumulation or loss of ice from the land.
Through an appreciation of eustatic and isostatic changes, we can recognize the links between coastal sea level change and the water and carbon cycles. For example, alterations in the balance of stores in the water cycle can lead to changes and, especially today, we are able to understand the impact of changes in the proportion of Co2 in the atmosphere on global climate and, in turn on the amount of ice on the land which is in turn related to both eustatic and isostatic slc.
Action:
1. Referring to page 135 (and other sources eg the www), describe the isostatic changes affecting the UK today. Include a copy of a similar map to that in figure 2 pp 135).
Sea Level change due to Tectonic activity.
Tectonic activity directly impacts on coasts globally due to:
· Mountain building (Orogenesis) and land uplift at destructive and collision plate margins that have resulted in relative fall in sea level in some locations.
· Local titling of land at destructive margins, for example, some ancient Mediterranean ports have been submerged and others have been stranded above the current sea level.
The 2004 Indian Ocean earthquake measuring about 9 on the Richter Scale killed over 275,000 people. The closest inhabited land was the island of Sumatra and this was hit by the resultant tsunami within 15minutes. The wave reached up to 15m high and devastated the city of Banda Aceh as well as other areas of the island. The situation was exacerbated by the tectonically induced sinking of the earth’s crust around Banda leading to the permanent flooding of large parts of the city.
The earthquake was caused by slippage along about 1600km of fault between the Indian and Burma plates. The seabed rose several metres, displacing an estimated 30km3 of water as well as triggering the tsunami. This elevation of the sea bed reduced the Indian Ocean’s capacity producing a permanent rise in sea level of an estimated 0.1mm.
Tectonic activity generates a huge amount of energy that is transferred by waves to the coast. The devastation and erosion of the coastline caused by the 2004 tsunami pays testament to the immense amount of energy harnessed by the waves. These one-off energy flows are very significant in causing coastal change and they exemplify the principle that most change in natural systems involves high-magnitude, low-frequency events.
Landforms caused by changing sea level.
Changing sea levels affect the shape of coastlines and form new landforms. Falling levels expose land formerly covered by the sea, creating emergent coastlines. A rise in sea level floods the coast and creates a submergent coastline.
Emergent coastal landforms
Raised beaches and associated features
Submergent coastal landforms
Rias and Fjords
Dalmatian coasts
Contemporary sea level change.
According the IPCC, sea levels stabilized about 3000 years BP and have only recently begun to change again. From the end of the 1800s there has been an average global sea level rise of approximately 1.7mm per year. Between 1993 and 2010, however, this increased to about 3.2mm p.a. The IPCC estimate that, by 2100, sea levels could rise by between 30cm and 100cm from current levels. However, there is likely to be considerable variation from place to place.
Current sea level change is largely though to be the product of thermal expansion plus the effect of melting ice from land stores such as Greenland, Antarctica and upland glaciers resulting from global warming (average increase of 0.85oC 1880 to 2010). These changes clearly show the link between coastal and glacial systems, water and carbon cycles through rises in atmospheric Co2 leading to an enhanced greenhouse effect that in turn changes global stores of water leading to greater volumes in the oceans and sea level rise.
Action:
2. Summarise the problems facing Kiribati due to changes in sea level.
3. Research, using the internet, how well Kiribati is coping with the effects of climate change.
4. Complete the activities 1 to 5 on pp139
I. Coastal Management – pp140 – 143
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8OJnIeozZYpu2Z50RtuPeZbVQS6RWANMltw_c1HYDhDZB-IdqvqK0b6W4Z8i8Ux6z3bP28fPxDs6Wy83ITk9pMVpIL5aLdCMu8GSI-hgsMwlklgZ1bUHYD8_vkZBgV-Q1Tk75H17XfSc/s640/Screen+Shot+2017-08-29+at+13.30.54.png)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9rQmElHw_GEY7rV9mvBlBsnfp8Qo3Gg9ZsT_34vrPomx4DDDkmLl6Hmu1rbtnGAENZy12bfdN78Lu0Rj5TqUqpm_Q-tkbkFnfTAp0llqTl_r-2yFKvdZOmKUPKHP8e8i7ItirPYR_Fmc/s640/Screen+Shot+2017-08-29+at+13.31.09.png)
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It is estimated that some 50% of the world’s population live within 60km of the coast and 75% of all large cities are on the coast. The coast is also under continued and considerable pressure from further development. The combination of these factors means that the coast is threatened by environmental damage and habitat destruction. Globally important ecosystems such as mangroves and coral reefs are being lost and damaged and the populations living in these areas are increasingly at risk from the effects of coastal erosion and flooding. Such risks are likely to grow as global climate warms and sea levels rise.
Action:
Explain how sea level rise increases the risks of erosion.
Traditionally, coastal management has been divided into Hard and Soft engineering approaches. These methods can temporarily prevent erosion, but they are expensive and this cost may be controversial especially at times of economic slowdown. Hard engineering and soft engineering are frequently used together although there has been increased interest in “soft” methods as these tend to be less expensive and less environmentally obtrusive and damaging.
Action:
Make notes and illustrations to outline the methods (listed below) of coastal management plus their relative advantages, disadvantages and costs.
Hard:
· Groynes
· Sea Walls
· Rip rap (rock armour)
· Revetments
· Breakwaters
Soft:
· Beach nourishment
· Cliff slope grading and drainage
· Dune stabilisation
· Marsh creation
Sustainable integrated management approaches.
In more recent years, coastal management has begun to adopt an approach that is more in keeping with a systems understanding of coastal environments. Although similar to soft engineering principles of working with nature and having long term sustainability, the new approache also aim to be more holistic and to take into account processes over larger areas of the coast rather than focusing on the needs at a specific, smaller and more localised stretch of coast. This, of course, allows principles of management based around sediment cells to be utilised. Such a philosophy underlies the Shoreline Management Plan (SMP).
The shoreline management plan has been developed to incorporate the views of all those involved in the development, management and use of the coast. This process is termed Intergrated Coastal Zone Management and aim to establish sustainable levels of economic and social activity; resolve environmental, social and economic challenges and conflicts; and to protect the coastal environment.
Action:
1. Explain the benefits of ICZM. Include references to coastal systems theory as appropriate and ensure that you demonstrate understanding of the term “holistic”.
Ref:
Pp143 of the course text
http://ec.europa.eu/environment/iczm/index_en.htm
2. Complete the activities on pp 142 of the text.
3. Complete the “stretch” activity on pp 143 of the text.
J. Case Study – Coastal Processes on The Holderness Coast – pp144 – 147
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Using the material in the course text and additional research, study the coastal processes on the Holderness coast.
K. Case Study – Risk and Opportunity in Odisha, India – pp148 – 153
Actions:
1. Review in depth the case study of Odisha (pp148 – 153) in the text, making appropriate notes to support your learning.
2. In class, complete activity 1, 2, 3 and 4.
3. HW: Activities 5 and 6 (For hand in and assessment)
4. In class: Activity 7 (Guided map interpretation and description)
5. Plan an answer to the following question (Q13/pp 155) using the Odisha case study:
“Much of the handwringing over sea level rise is precisely because so much of the world’s population lives near the ocean”.
For a coastline you have studied, analyse the respective roles of resilience, mitigation and adaptation in maintaining coastal communities. 20 Marks
L. Practice questions – pp154 – 155
Completion of the practice questions in class under exam conditions (ish).
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