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COAST RISKS AND MANAGMENT - Coggle Diagram
COAST RISKS AND MANAGMENT
RISKS TO COASTAL ENVIRONMENTS
COASTALISATION = INCREASED VUNRABILITY is the movement of people towards the coast. Despite having a high flood risk, may people move to the coast due to tourism, high-yield agricultural lands, or housing pressure. Coastalisation can increase the environmental vulnerability of these locals to flooding due to storm surges
STORM SURGES
A storm surge occurs when there is a short-term change in sea level, which may be due to low
pressure during a depression or tropical cyclone.
INCREASE EFFECT
Subsidence of the land - through tectonic activity or post-glacial adjustment.
Removing natural vegetation - Mangrove forests are the most productive and complex ecosystem in the world. Mangroves also provide protection against extreme weather events like cyclones which are very common in the Bay of Bengal. However, due to pressure for land space, much mangrove forests are destroyed for tourism, local industry, or housing plains.
Global Warming - As the surface of oceans get warmer, it is estimated that the frequency and intensity of storms will increase, and so the severity of storm surges and flooding is also expected to increase.
CONSEQUENCES FOR THE COMMUNITY
Some areas of the coast may have significantly reduced house and land prices (as the area becomes known to be at significant risk). This can lead to economic loss for homeowners and local coastal economies. In the UK, many insurers don’t provide home insurance to people living along coastlines that are at extreme risk of erosion or storm surges. Storm surges also damage the environment by destroying plant successions and damaging many coastal landforms. Depositional landforms, due to their unconsolidated nature, are most likely to be destroyed. Also, erosion may take place at accelerated rates or higher up along the cliff face, which can increase the risk of collapse.
ENVIRONMENTAL REFUGEES
Globally, more than 1 billion people live on coasts that are at risk from coastal flooding and 50% of the world’s population currently live within 200km of the coast. As storm surges and erosion along some coastlines are predicted to increase, so too is the volume of environmental refugees displaced internally or internationally. People may lose their homes, way of life and culture as they are forced to migrate to avoid the rising eustatic sea level and the rising risk of coastal flooding.
COASTAL MANAGMENT
APPROACHES
Approaches to coastal management have changed greatly due to new knowledge and research about the positive and negative impacts that management can have on a coastline.
New approaches have been created, though the specific strategies used can mostly be classified into two types - hard and soft engineering. Hard and soft engineering both relate to traditional approaches to coastal management.
'There is erosion occurring in this area, so lets build a beach or sea wall to reduce the erosion’. These approaches are a direct solution to the problem that is occuring.
Hold the line – Defences are built to try and keep the shore where it is.
● Managed realignment – Coastline moves inland naturally but managed.
● Advance the line – Defence are built to try and move the shore seawards.
● Do nothing – No defences are put in place and the coast is allowed to erode.
FACTORS TO CONCIDER
Economic value of assets that could be protected is looked at, for example the important natural gas terminal at Easington would be protected however farmland and caravan parks wouldn’t
The technical feasibility of engineering solutions, for example a sea wall may not be possible for a certain location.
The ecological and cultural value of land. For example, it may be desirable to protect historic sites or SSSI.
SUSTAINABLE COASTAL MANAGMENT
Managing natural resources like fish, water, farmland to ensure long-term productivity.
Creating alternative livelihoods before people lose their existing jobs.
Educating communities about the need and how to adapt.
Monitoring coastal changes and then adapting or mitigating.
Managing flood risk or relocating if needed.
CONFLICT OVER POLICY DECISONS
winners and losers .
Winners = those who benefit economically (e.g. their homes and businesses are protected), environmentally (e.g. habitats are protected) and socially (community ties still remain in place, people still have jobs so less stress and worrying). Losers = those who lose their property, lose a job, or have to relocate elsewhere. Communities and homeowners have a strong attachment to a place so losing their properties and their social networks is a great loss. This will make them financially worse off and many people may feel lonely if forced to move and may be angered if areas are not chosen to be protected. Business owners may be angered if nothing is done to protect the area in which they have their business, which could cause them to lose profitability and regular clients
. DEFRA funding has been reduced by the central government since 2010 so they cannot invest in coastal management in all areas and now have to prioritise their funding in the most important locations. Some people may feel aggrieved by this.
IMPACT ON SEDIMENT CELL
Coastal management has a variety of impacts on sediment cells and any form of intervention will cause some kind of impact.
Installing a sea wall would reflect wave energy downdrift increasing wave energy and erosion elsewhere on the coastline.
Less erosion occurs in these areas with the sea wall , so there is also less sediment in the areas with increased wave energy .
Less sediment reduces the beach size , so the cliff is more exposed to erosion from the higher energy waves.
Building groynes has the same effect on downdrift areas as longshore drift can no longer transport sediment away from one stretch of coastline.
SUPPORT OF NO ACTIVE INTERVENTION Coastal managers produce SMP for an entire area so they have to see what kind of impacts other may have if the coast is managed in one specific area
● Local authorities and DEFRA have had their budgets reduced as central government funding since 2010 has dropped and so they cannot invest in coastal management in all areas, they have to prioritise their funding to the most important places
COASTAL DECISION MAKING
COST BENIFIT ANALYSIS
This is an analysis that is carried out before any form of coastal management takes place. The cost involved include construction, demolition, maintenance etc. is then compared to the expected benefits like the value of land saved, homes and businesses protected. Costs and benefits include both tangible and intangible things For a project to be given the go ahead, the expected benefits have to outweigh the cost
INTERFRACTED COASTAL ZONE MANAGMENT ICZM
A coastal area (sediment cell) is managed as a whole. This often involves management between different political boundaries e.g in the UK different councils will have to work and manage coasts together.
▪ The ICZM recognises the importance of the coast for people’s livelihoods.
▪ The ICZM recognises that coastal management must be sustainable whereby economic development is important but this should come at a cost for the environment.
The ICZM must involve all stakeholders, plan for the long term and try to work with natural process and not against them.
SHORELINE MANAGMENT PLAN SMPs
For each sediment cell in the UK, an SMP has been created to help with coastline management. Each SMP identifies all of the activities, both natural and human which occur within the coastline area of each sediment cell. The sediment cells are considered to be closed for the purposes of management, although in reality there will be some exchanges between the different sediment cells. SMP’s are recommended for all sections of English and Welsh coastlines by DEFRA (governing body responsible for majority of environmental protection in the UK).