Coastal Opportunities & Hazards | Geography for GCSE/IGCSE - Year 11 PDF Download

Coastal Opportunities

• The coast offers various opportunities for development, such as:
  • Homes
  • Shops
  • Hotels
  • Roads
  • Schools
  • Restaurants, and more.
• Nature reserves provide spaces for activities like swimming and sports.
• Industries near the coast engage in activities like fishing, aquaculture, and tourism.
• Agriculture thrives in coastal regions, supporting farming activities.
• Ports and harbours serve as crucial points for transportation and trade.

Coastal Hazards

• Coastal hazards can stem from either natural occurrences or human activities.
• Natural hazards comprise storms, flooding, and tsunamis.
• Human-induced actions lead to a range of problems, as outlined in the table below:

Natural coastal hazards

• Coastal hazards result from various factors:
  a. Storm surges: Swift sea level rises caused by low-pressure storms like tropical storms.
  b. Storm tides: Occur during the simultaneous presence of high tide and low-pressure storms.
  c. Tsunamis: Massive sea waves triggered by underwater earthquakes, with greater impact closer to the coast.
  d. King tides.
  e. Sea level rise due to global warming.
  f. High river discharge following a storm, particularly problematic during spring tides, leading to estuarine water backflow and flooding.
• Any combination of these hazards can result in coastal flooding.
• While developing nations often experience the most significant impacts, the highest financial burdens typically fall on more economically developed countries (MEDCs).

Tropical storms

• Hurricanes, typhoons, and cyclones are all types of tropical storms, differing only in their formation locations:
  a. Hurricanes originate in the tropical North Atlantic Ocean and Northeast Pacific.
  b. Typhoons develop in the Northwest Pacific Ocean.
  c. Cyclones form in the South Pacific and Indian Ocean.
• In the northern hemisphere, these storms typically form between May and November, while in the southern hemisphere, they occur from October to May.
• Tropical storms can devastate coastal regions and cause fatalities, with impacts exacerbated in less economically developed countries (LEDCs) due to limited financial resources.
• Additional consequences include:
  a. Destruction of buildings and infrastructure.
  b. Intense rainfall and storm surges.
  c. Loss of ecosystems, vegetation, land, crops, and wildlife.
  d. Maritime accidents resulting in shipwrecks.
  e. Disruption of power and communication networks.
  f. Significant financial costs, especially in densely populated areas.
• Managing tropical storms is challenging, but strategies to mitigate risks include:
  a. Construction of sea walls and artificial levees to prevent flooding.
  b. Implementation of evacuation plans for the population.
  c. Utilization of satellite tracking and early warning systems.
  d. Building resilient homes and structures capable of withstanding strong winds.
  e. Elevating homes above storm surge levels and installing sturdy window shutters.
  f. Stockpiling emergency supplies and establishing shelters.
  g. Obtaining storm insurance coverage.

Changing sea levels

• Rising sea levels lead to submergent coastlines characterized by features like rias and fjords.
• Falling sea levels create emergent coastlines, showcasing relic features such as raised beaches, cliffs with caves, and arches.
• Sea levels have fluctuated numerous times throughout history.
• During the last Ice Age, sea levels dropped due to the accumulation of water in glaciers and ice sheets, then rose again as the ice melted.
• Global warming is closely linked to sea level rise, which poses a significant threat to many low-lying coasts and islands.
• Pacific Ocean islands like Kiribati and Tuvalu face the risk of complete submersion due to rising sea levels.
• The challenge intensifies as many densely populated areas are situated on coastal lowlands.
• Major cities such as New York and Miami in the US are particularly vulnerable to sea level rise because they are built at sea level.

Influence of geology

• Geology plays a pivotal role in shaping coastlines across various temporal, spatial, and locational contexts.
• Coastal areas comprised of softer rocks like sands and clays are susceptible to erosion by destructive waves, resulting in the formation of low, flat landscapes such as bays and beaches.
• Conversely, coastlines characterized by more resistant, harder rock types undergo slower erosion processes, yielding rugged landscapes like headlands.
• Variations in rock hardness influence the morphology and features of cliffs, distinguishing them between hard and soft rock formations.

Erosion 

• Erosion along coastlines is a global phenomenon, but its impact is most profoundly felt at the local scale, where geology plays the most significant role.
• Areas composed of less resistant rock types like limestone, sandstone, and boulder clay erode more rapidly compared to coastlines consisting of more resistant rock such as granite.
• Longshore drift and destructive waves, by removing sand from beaches, expose the base of cliffs to intensified erosive processes with higher energy levels.
• Coastal management practices, such as the installation of groynes to mitigate longshore drift, can inadvertently exacerbate erosion rates elsewhere by depleting sediment and creating shallow beaches that are more susceptible to erosion.
• Coastal erosion poses a significant threat to many islands, endangering residents and tourist resorts.
• The acceleration of erosion is further compounded by tourist and coastal developments, which often remove natural coastal protections such as mangroves, coral reefs, sand dunes, and salt marshes.