Predicted impacts of climate change on the coast (WJEC Eduqas GCSE Geography B): Revision Note

Specification links

The notes on this page cover part 2.1.4 of the WJEC Eduqas B specification – What are the predicted impacts of climate change on coastal landscapes and communities?

• The potential impacts of climate change on coastal communities in at least two countries at different levels of development.

• Management challenges which arise from sea level rise and the increased frequency of storms.

General effects of climate change on coasts

• As global sea temperatures increase, water levels rise through melting ice caps and seawater expansion

• A warmer atmosphere leads to more intense and frequent storms, creating powerful, destructive waves

• A warm atmosphere can hold more water vapour, which will lead to the following:

  • Higher levels of precipitation and increased rates of weathering and erosion

  • Increased cliff instability, leading to greater levels of landslips and falls

• Climate change can impact the whole of the world's coastline, particularly those areas where the cliffs are made from softer rock and clay or are lying close to sea level and can, therefore, flood

• Of the 10 world's largest cities, 8 are in coastal areas

  • Mumbai, home to 18.4 million people, is only 10 metres above sea level 

  • Other cities like New York, Singapore and New Orleans are also at risk 

• It is estimated that by 2030, 950 million people around the world will live in low-elevation coastal zones (LECZ)

• LECZs are often densely populated due to:

  • Attractive scenery and beaches

  • Deltas are fertile and ideal for agriculture

  • Suitable for ports and trade

• Countries and regions which are particularly low-lying include:

  • Bangladesh – over 10% of the land is 1 m or less above sea level

  • Netherlands - 27% of the country is below sea level and protected by sea defences

• Most affected coastal communities are those living on the world's major river deltas, such as

  • Bangladesh, Egypt, Nigeria, Vietnam and Cambodia 

• Small island developing states (SIDS) such as Kiribati, Tuvalu and the Maldives are very low-lying

  • The Maldives has an average height of 2 m above sea level, with the highest point being 2.4 m

  • Just a 1-metre rise in sea level would flood up to 75% of the land in each of these nations

• Currently, 65 million people represent 58 SIDS

• Many SIDS are small, remote and isolated regions

• The standard of living ranges from US $51,000 in Singapore to US $830 in Comoros

• Many at-risk cities are in developing countries

  • Poor neighbourhoods are often in low-lying areas

  • Beside waterways or seafronts that are prone to flooding

• Sea level rise may force some people to become environmental refugees

Reasons for vulnerability to coastal erosion and flooding

• There are many reasons why some communities are more vulnerable than others

• These reasons can be divided into

  • Physical

  • Social

  • Economic

• The image below explains these reasons in more detail

Case study: climate change and the Maldives

Location and background

• The Republic of Maldives is an archipelago of around 1,192 coral islands grouped in 26 atolls, located in the Indian Ocean, southwest of India and Sri Lanka

• It is the lowest country in the world — the average ground level is just 1.5 metres above sea level

• The population is approximately 527,799 people (as of 2024)

• The Maldives is a MIC with a Gross National Income (GNI) per capita of $11,070 in 2023

• The Maldives has a tropical climate with:

  • Warm temperatures

  • Large number of sunshine hours

  • Little seasonal variation

  • High humidity year-round

Problems facing the Maldives

• The challenges facing the Maldives include

  • Coastal erosion

  • Freshwater scarcity

  • Infrastructure damage

  • Population displacement

  • Adaptation strategies that balance socio-economic needs with environmental protection

Coastal erosion

• Coral reefs, which act as storm buffers, are damaged by ocean warming and pollution, weakening their natural protection

• Without the protection of coral reefs, coastal erosion has severe consequences for the integrity of the shoreline, infrastructure, and local industries like fishing and tourism

  • Over the last 30 years, frequent flooding of the islands has caused ongoing problems for the Maldives

  • The majority of issues arise when storms in the northern Indian Ocean coincide with the highest spring tides

  • More intense tropical storms cause greater damage to homes and flood the coastline with tropical storm-fuelled storm surges

Freshwater scarcity

• As the sea levels rise, it puts pressure on already scarce freshwater resources, making it harder to obtain drinking water

• More than 90% of the islands in the Maldives have experienced saltwater ingress, with 97% of the country no longer having access to fresh groundwater

• This has forced 77% of Maldivians to rely on rainwater for their drinking supply

• Importing water from other countries is not a sustainable solution

• The Maldivian government, with support of the United Nations Development Programme (UNDP) and Adaptation Fund, has allocated $8.9 million in government funds for an Integrated Water Resources Management (IWRM) program

• This aims to improve access to clean water and boost the water supply system's capacity

Infrastructure damage

• The government is relying on hard engineering to hold the line against rising sea levels

• However, these methods are expensive and have negative impacts, such as increasing erosion elsewhere 

  • Malé, the capital, is surrounded by a 3-meter sea wall that took 14 years to construct and cost $63 million

  • Japan paid 99% of the cost for this sea defence, as the Maldives was unable to pay for this

  • The sea wall needs constant repair, and the cost is met through local tourist taxes

  • The remaining islands are still under threat of flooding

• The tourism business is also at risk

  • Travel and tourism is the Maldives' most important industry—it brings in 90% of the country's revenue

  • The 2004 Indian Ocean tsunami severely impacted the Maldives, causing widespread damage to infrastructure and devastating the tourism and fishing industries

  • The country rapidly began to rebuild, and by early 2005, many resorts were operational, with governments urging tourists to return to aid recovery

  • However, the Maldives remains vulnerable to tsunamis from nearby or distant earthquakes

Climate refugees

• A climate refugee is a person who must leave their home and community because of the effects of climate change and global warming

  • Climate refugees belong to a larger group of migrants known as environmental refugees

• The IPCC has predicted that the Maldives will be uninhabitable by 2100, due to sea levels rising by 9 mm/year

• Fourteen islands have already had to be abandoned due to intense coastal erosion and natural disasters

• Many more islanders will have to abandon their homes, losing their livelihoods and way of life, as well as their culture

Adaptation

• A completely new island has been created by dredging sand from nearby lagoons

• Called Hulhumalé, it means ‘New Malé’, but it is also called the City of Hope

• When the second phase of development is finished, the 2-metre-high island will cover 420 hectares and house 160,000 people, mainly in large blocks of social housing

Case study: climate change and the UK

Location and background

• The UK is an island country located off the northwest coast of mainland Europe, surrounded by the Atlantic Ocean, the North Sea, and the English Channel

• The UK's long coastline is accessible to its population

• Fishing, ports, and offshore energy generation are just a few of the key economic activities that take place along the UK coast

• Many coastal communities have to deal with

  • An ageing population and retirees

  • Young people leaving the area

  • A percentage of people on benefits

  • Inward and outward migration

  • Physical isolation, poor housing, relying too heavily on tourism, seasonal jobs, low income, and pressure on services in the summer

Problems facing the UK

• By 2080, climate change will pose a significant risk to UK coastal communities, including increased coastal flooding and erosion due to sea-level rise and more intense storms

• These impacts threaten homes, infrastructure (such as power stations, roads, and sewage works), and sensitive coastal habitats like salt marshes and dunes

• The UK's original defences are ageing, and there are insufficient funds to upgrade them against the increased frequency and strength of storms

• The North Sea is famous for its winter storms, and they often create storm surges that affect communities along the east coast of the UK

  • These storm surges can be 2 m above normal sea level and can wash over coastal defences and move inland, flooding coastal communities

The Holderness Coast

• The Holderness Coastline is located on the East Coast of Yorkshire and runs for 61 km

• It stretches from Flamborough Head in the north down to Spurn Head, where it meets the Humber Estuary in the south

• It is the fastest-eroding coastline in Europe at 2 m per year

• It is made of soft boulder clay and chalk

• The coastline has naturally narrow beaches, which give less protection from erosion, as wave power is not reduced

• Longshore drift is the dominant process due to the North Sea waves

• Waves along the coastline have a long fetch (travel long distances), which increases wave energy

• The biggest issue with the Holderness coastline is that it is retreating too quickly

Management of the Holderness Coast

• Bridlington is protected by a 4.7 km-long sea wall

• Gabions have been built at Skipsea

• Hornsea's cliffs are formed from soft boulder clay

  • As a popular tourist destination, management is aimed at protecting hotels, arcades and creating a sandy beach

  • Hornsea has spent money on repairing its wooden groynes at a cost of £5.2 million

  • It also has a concrete seawall

  • Recently, a stone and steel gabion, along with a concrete revetment, has been built south of Hornsea, helping to protect the caravan park

• Riprap, at a cost of £2 million, and groynes and beach nourishment at Mappleton have produced a sandy beach and protect the town 

• Withernsea has a sea wall, groynes, riprap and beach nourishment to widen the beach and reduce wave energy

• Approximately 2.25% of all UK gas comes through the gas terminal at Easington, and £4.5 million was spent on riprap, but the scheme protects the terminal and not the village

• Spurn Head is protected with groynes and rock armour

Conflicts

• Careful management of coastal regions is necessary to ensure sustainability

• Conflict arises when coastal development is seen as being given a higher priority than overall coastal conservation

• Management along the Holderness Coast has been successful in part, with the village of Mappleton and the B1242 road no longer at risk from erosion

• Due to the use of groynes at Mappleton, sediment has been prevented from moving south, which has increased erosion at Great Cowden 

• Erosion has destroyed farms, along with the loss of 100 chalets at the Golden Sands Holiday Park

• Locals have disagreed about where sea defences are located, especially if community land is not protected

• Some sea defences negatively impact tourism and reduce the amount of money coming into the area

• Spurn Head is at risk of losing habitats due to a lack of sediment to maintain the spit

• Overall, maintaining coastal defences is expensive and the cost may be too great to continue defending an area that is eroding quickly and will continue to erode 

London and the Thames Gateway

• The River Thames estuary, located to the east of London, is at risk from storm surges

• This area, known as the Thames Gateway, is characterised by a narrow, funnel-shaped coastline between Essex and Kent

• During storms, this shape causes the sea to be pushed up the Thames towards London

• Additionally, the coastline has been gradually sinking since the end of the last ice age in the UK, which was about 10,000 years ago

• This process is known as postglacial rebound, where the land slowly adjusts after the weight of ice has melted away

• The Thames Gateway is slowly sinking at about 2 mm a year compared to the current sea levels 

• At the same time, climate change is causing the sea levels in the Thames Estuary to rise by approximately 3 mm each year

• So the combined effect of sea level rise and postglacial rebound means that sea levels in this area are rising by about 5 to 6 mm per year

Holding the Thames Estuary line

• Situated to the east of the City of London, the Thames Flood Barrier was completed in 1982 and protects 125 million people from tidal surges coming up the river from the North Sea

  

• Since it opened, it has been closed 221 times to protect London

• However, with a warming climate and higher sea levels, it's being used more often and the barrier may not be big enough to protect London from future storm surges

• The Thames Estuary 2100 Plan (TE2100) highlighted that London needs to future-proof against 2.7 m + current levels of flooding.

• The TE2100 Plan has 3 management strategies

• Continue to renew and replace existing embankments, sea walls and sluices in the Thames Gateway

• Increase the amount of inter-tidal habitat by 876 hectares, helping to store floodwater as it moves up the estuary during a tidal surge

• Consider building a new, larger barrier at Long Reach to the east of the existing barrier; the cost of this construction would be between £6 and £7 billion

• The UK government will decide on the options by 2040