Q1: Coastal Landscapes 15 marks

Coastal Processes Produce Landforms

Types of Waves

Biological weathering Rocks are broken down where they are and do not get moved. Physical weathering Freeze-Thaw Biological weathering Seeds fall into cracks of rocks. Seed grows and as roots grow they force rocks apart . Chemical weathering Carbonation CO2 is absorbed by H2O to create carbonic acid (H2CO2)

Rocks are broken down and carried away by something - such as the sea Erosion Rocks are broken down and carried away by something - such as the sea

Material shifts down a slope under the force of gravity. Mass Movement Material shifts down a slope under the force of gravity. Rocks and loose material shift down a slope - e.g. a cliff Mass movements cause coasts to retreat more rapidly Soil Creep Slowest downhill movement Gravity pulls water in the soil downhill Soil particles move with the water Heavy rainfall will speed up movement Slope appears to have ripples Ripples are known at ‘terracettes’. Slumping Large area of land moves down a slope Common on clay cliffs Dry weather makes rock contract & crack When it rains, water gets into cracks Soil becomes saturated Large piece of rock is pulled down the cliff

Landforms created by coastal erosion: Cliffs & Wave-Cut Platforms

Landforms created by coastal erosion: Headlands & Bays

Landforms created by coastal erosion: Cave, arch, stack & stump

Landforms created by coastal deposition: Longshore Drift

Landforms created by coastal deposition: Beaches Beaches are formed by deposition between the high water and low water marks. They are formed by constructive waves.

Landforms created by coastal deposition: Spits

Landforms created by coastal deposition: Bars

Coastal Landforms are subject to change

What affects the rate of coastal erosion? Fetch How far the wave has travelled. The longer the fetch, the stronger the waves. Geology Softer rocks will erode more quickly. However, harder rocks sticking out at headlands will also be vulnerable to the full force of the waves’ power Defence If the coast is defended it will slow down rates of erosion. However, groynes will speed up erosion further down the coast if it is not defended.

The effects of coastal recession on people and the environment Happisburgh 25 properties & lifeboat launch station lost since 1995. Grade 1 listed church estimated to be lost to the sea by 2020. Walton on the Naze Present rates of erosion of 1.5m per year means the tower will be lost to the sea. The area around the tower is used for recreation & is not worth spending money to defend it. Westward Ho! Coastal golf courses are at high risk. The Royal North Devon Golf Club at Westward Ho! Is losing its 7th & 8th holes. Exeter to Penzance Railway The sea often washes over the tracks. Once 160 passengers were stranded for 4 hours because the sea made the electrics fail. Barton on Sea Since 1975 the seaside café & Manor Lodge had to be demolished as they became dangerously close to the sea. In 2004 the coastal footpath was closed & re-sited further back from the cliff edge.

Predicting and preventing the effects of coastal flooding: Forecasting The Met Office predicts the likelihood of a flood. This is communicated through weather forecasts and news on TV, radio, websites and apps. The Environment Agency monitors sea conditions 24/7. The Storm Tide Forecasting Service provides coastal flooding info on a 24 hour flood hotline and on their website.

Predicting and preventing the effects of coastal flooding: Building Design In Bangladesh all 1 & 2 storey buildings must have an external staircase to the roof. Houses along the coast at Malibu in California are built on stilts to protect them from storm tides. Properties built in areas of flood risk have designs to protect them from the wind, rain and storms.

Predicting and preventing the effects of coastal flooding: Planning Planning permission may not be granted if the land is at risk from or has a history of flooding. The Thames Flood Barrier was completed in 1982. In 2010 the Environment Agency installed new flood walls along the river along with other flood defences to protect London against future flooding. In Bangladesh the Coastal Embankment project has led to the building of 12 sea-facing flood walls & 500 flood shelters.

Predicting and preventing the effects of coastal flooding: Education Governments give advice to the public via websites about how to protect homes and what to do if a flood occurs. In Bangladesh many coastal areas have flood warning systems. In King’s Lynn, Norfolk, there is a flood siren. The council employs officers to visit homes to warn people & help them prepare if flooding is forecast.

Large rocks placed in front of the cliff Hard Engineering Major construction work that aims to prevent floods & usually not great to look at! Revetments Rip Rap Recurved Seawalls Slatted wooden structures at the base of a cliff Absorb wave energy through slats Effective for many years Relatively cheap Not effective in storms Regular maintenance Makes beach inaccessible for tourists Large rocks placed in front of the cliff Breaks up wave energy Effective for many years Cheap Not effective in storms Unattractive Makes beach inaccessible for tourists Usually concrete wall, modern ones have a curve Reflect & absorb wave energy Effective for many years Visible & therefore makes people feel safe Very expensive Unattractive

Wire cages filled with stones Hard Engineering Groynes Gabions Offshore Reefs Usually wooden structures stretch from the coastline in right-angles out into sea Prevent longshore drift Keeps beach in place for tourist industry Effective for many years Starves beaches further down the coast of sediment > speeds up erosion elsewhere Unattractive Wire cages filled with stones Rock cages breaks up wave energy Relatively cheap Not as effective as other methods Wire cages can break – need to be well secured Concrete blocks/natural boulders sunk offshore Waves break further offshore > reduces their power to erode Less wave energy will allow more sand to build up on beach Difficult to install Storms may remove them

Cliff cut back with new gentle slope = reduce slumping Soft Engineering Work with natural processes aiming to reduce effects of floods – tend to blend in well Beach Replenishment Cliff Regrading Managed Retreat Adding sand/pebbles to the beach Looks natural & is cheap Keeps beach in place for tourist industry Beach = natural defence Requires constant maintenance Noisy & heavy machinery will disrupt homes & businesses Affects plant & marine life Cliff cut back with new gentle slope = reduce slumping Covered in netting to encourage vegetation Natural habitat > encourages wildlife Not as effective as other methods Homes on cliff may need to be demolished to allow work to take place Allow nature to take its course & flooding to occur Cheap Creates wetland habitats for plants & birds Some people will lose their land Difficult to estimate how much land will be lost – especially in face of rising sea levels

Coastal Management

Managing the coast: Walton-on-the-Naze, Essex 1977: Groyne, Cliff & Seawall Heaven! Groynes built to stop longshore drift moving sediment from the south to the north Cliff regraded and drainage channels installed to make cliffs stable Slopes planted with gorse & nettles to stop people climbing on the cliffs Seawall built to protect the bottom of the cliffs as they are made up of soft clay 1998: Rip-Rap’s Looking Great! Rip-Rap placed along the bottom of the cliffs. 300 tonnes of Leicester granite placed around the Tower Breakwater 1999: Beach Replenishment’s Mighty Fine! Beach replenished with sand & gravel from Harwich Harbour Alternative case studies: Happisburgh, Norfolk or Barton on Sea, Hampshire