georgraphy case studies

• Boscastle


  • Relatively impermeable upland area
  • Steep valley sides converging as they run towards the sea, funnelling water
  • In the path of westerly winds
• Exceptionally wet sale extra saturated ground
• Summer storms
• 20 business properties destroyed and bridges washed away
• 43m wall of water (60 kph) contained huge boulders and trees
• 45 million flood defence scheme (2008)
• Flood defence measures


  1. River channel widened

  2. Trees near river removed

  3. River channel deepened to carry higher flows

  4. New flood defence wall

  5. Trash screen installed
• Extra factors causing the flood

  • Artificial narrowing of the river
  • Trees alongside river blocked it
  • Building alongside river without leaving enough space for flood water
• Low winter rainfall caused by position of the Jet Stream
• Rising temperature due to climate change
• Tapping deeper into groundwater and water overuse
• Anticyclones blocking out depressions
• Most hydroelectric power (HEP) dams stopped producing electricity
• Cracks appeared in buildings and roads
• State lost 17,100 agricultural jobs due to the drought
• Many homeowners suffered water shortages
• Soil dried leading to dust storms and wildfires
• Drought response measures


  1. Watering gardens and driveways banned

  2. Restaurants could only serve water if requested

  3. Agricultural users had to provide the state with reports of how they'll reduce consumption
• Farmers in central valley lost 38 million dollars per day
• 687 million dollars of government savings were paid to farmers and homeowners who lost property in wildfires
• Holderness Coast


  East coast of England, extends from Flamborough Head to Spurn Point
• One of Europe's fastest eroding coastlines (2m per year)
• Holderness Coast


  • Glacial tilt (soft boulder clay) - rapidly eroding when saturated
  • Strong prevailing winds create longshore drift, moving material south
  • 2 main rocks: Chalk & boulder clay
• Chalk resists large scale erosion (features like Flamborough Head)
• Boulder clay cliffs to south easily eroded
• Forms Holderness Bay
• Weather factors affecting erosion

  • Winter storms
  • Stronger waves
  • Storm surges
  • Rain intensifies sub-aerial weathering
  • Saturated cliffs lead to slumping
• Coastal processes


  • Destructive waves erode beaches and cliffs
  • Longshore drift carries material south
  • Low energy tides cause formation of spit, dunes and mudflats
• Human factors affecting erosion


  • Increasing population, holiday and retirement
  • Global warming: rise in sea level and increasing storminess
  • Interference with natural processes: unsustainable defence systems like groynes
• River Wye


  5th longest river in UK, 150 miles long, source in Plynlimon Hills, mouth in Bristol Channel, located in Wales
• Upper course characteristics


  • Impermeable shales and gritstones
  • Igneous rocks (granite) more resistant to erosion, forming mountains
  • More tributaries
  • More surface runoff (impermeable)
  • Alternating bands of hard and soft rock near Rhayader result in white water rapids
• Lower course characteristics


  • Weak mudstone and sandstone south of Hereford easily eroded into wide, flat valley
  • Floodplains formed by deposition south of Hereford
  • Carboniferous limestone between Goodrich and Chepstow eroded into steep-sided Wye Valley gorge
• High rainfall (725 mm - 2500 mm) - water is fast flowing/high energy leading to high vertical erosion
• Forms waterfalls (Cleddon Falls)
• Human factors affecting flood risk

  • Deforestation reduces interception, more rainfall reaches ground
  • Urban development adds impermeable surfaces, increasing runoff
  • Agricultural crops intercept rainfall, reducing runoff
• Costa Rica


  Country in Central America, between Panama and Nicaragua, between Pacific Ocean and Caribbean Sea
• One quarter of Costa Rica is protected by nature reserves
• Sustainable rainforest management


  • Trees and crops grown together, some crops benefit from shelter
  • Trees prevent soil erosion, crops benefit from leaf litter
  • Trees cut down when they reach a certain height, maintaining canopy height
  • Trees planted to replace lost trees, but lacks biodiversity of primary rainforests
• Ecotourism


  A type of sustainable development, aims to conserve natural environment and local communities
• Ecotourist activities


  • Bird watching
  • Canopy exploration
  • Horseback riding
  • Sea and river kayaking
  • Walking and hiking
  • White water rafting
  • Yoga and meditation