2 - The Natural Environment

Geography case studies for theme 2

Where is Tohoku located

North-eastern Japan

Describe the plate situation at Tohoku

Pacific Plate subducts beneath North American Plate

Describe the earthquake at Tohoku

Magnitude 9

11 March 2011

Why did an earthquake occur at Tohoku

Subduction of Pacific plate caused strain to build up in crust

Suddenly released as seismic energy

How many people were killed in the Tohoku earthquake

15,900

How many people were injured in the Tohoku earthquake

6,000

How many people went missing in the Tohoku earthquake

2,500

How many homes were destroyed/damaged in the Tohoku earthquake

450,000

What critical infrastructure was destroyed in the Tohoku earthquake

Roads

Railways

Ports

Fukushima nuclear plant suffered immense destruction

Primary community impacts of the Tohoku earthquake

Displacement

Loss of property

Disruption of essential services

What were the secondary impacts of the Tohoku earthquake

long-term disruption to communities

Industries halted

Agriculture damaged

Nuclear disaster at Fukushima → widespread fear & exclusion zones

What were the secondary impacts on the environment from the Tohoku earthquake

Soil contamination

Debris accumulation

Costal erosion

What were some management strategies following the Tohoku earthquake

Sea walls in costal regions

Earthquake-resistant buildings

Tsunami evacuation routes

Early warning systems

Nationwide drills

Where is Montserrat located

Its a small island in the Caribbean

What plate boundary type is Montserrat located on

Destructive plate boundary

Plate situation at Montserrat

Atlantic Plate subducts beneath the Caribbean plate

When did the Montserrat Soufrière Hills eruption occur

18 July 1995

How did the Montserrat Soufrière Hills eruption occur

Subduction of Atlantic plate caused oceanic crust to melt under high pressure

Producing viscous, gas-rich magma

Rose through crust due to buoyancy and convection currents

Generated pyroclastic flows, ashfall and lahars

How any people were killed by the Montserrat Soufrière Hills eruption

19 people

How many residents had to evacuate after the Montserrat Soufrière Hills eruption

7,000

What was the capital city of Montserrat and what happened to it following the Montserrat Soufrière Hills eruption

Plymouth - destroyed and abandoned

Infrastructure damaged by the Montserrat Soufrière Hills eruption

Homes

Roads

Public buildings

Farmland

Businesses

Environmental impacts of Montserrat Soufrière Hills eruption

Wildlife habitats and agricultural land destroyed by pyroclastic flows and ashfall

Montserrat response to Montserrat Soufrière Hills eruption

Monitoring

Prediction

Protection

Monitoring strategies in Montserrat

Seismographs

Gas sensors

Ground deformation measurements

Prediction strategies in Montserrat

Hazard maps

Early warning systems

Protection strategies in Montserrat

Exclusion zones

Enforced evacuation plans

Relocation of homes and infrastructure

Long term benefits of Montserrat Soufrière Hills eruption

Tourism

Creates jobs for residents

Where is Bangladesh located

South Asia

Where is Bangladesh situated

Delta of the:

Ganges

Brahmaputra

Meghna

Why is Bangladesh vulnerable to flooding

Over 80% of the country is less than 10m above sea level.

Monsoon rainfall

How much rainfall does Bangladesh experience

2,000 - 4,000 mm per year

How is climate change intensifying the problem in Bangladesh

Rising sea levels

Increased frequency of extreme rainfall events

TMT

Floods are becoming:

Deeper

Faster

↑ Unpredictable

What are the socio-economic impacts of flooding in Bangladesh

Large-scale evac

Displacement

Waterborne disease (cholera)

Disrupts education (decimated schools)

What are the environmental impacts of flooding in Bangladesh

Destroy crops

Causes erosion

Riverbanks collapse

Loss of wildlife habitats

Contamination of water supplies

Positive impacts of flooding in Bangladesh

Deposits nutrient-rich silt → improves soil fertility

Measures taken by Bangladesh to reduce likelihood of flooding

Embankments

Levees

Dredging

Social measures taken by Bangladesh to reduce impacts of flooding

Early warning systems

Community evacuation planning

Floating homes

Raised flood shelters

Flood-resilient crops

Where is Winchester located

Southern England

River in Winchester

Itchen

Social impacts of flooding in Winchester

Disrupts communities

Damages homes

Isolate residents

Structural impacts of flooding in Winchester

Roads & railways closed

Historic buildings damaged

Environmental impacts of flooding in Winchester

Floodwaters erode riverbanks

Damage wildlife habitats

Carry pollutants into rivers

Hard engineering strategies used in Winchester when flooding.

Flood walls

Embankments

Culverts

Soft engineering strategies used in Winchester when flooding.

River restoration

Floodplain zoning

Creation of wetland storage areas (winchester college fields)

What were measures put in place to reduce impacts of future flooding in Winchester

Early warning systems

Emergency response plans

Barton-on-sea location

Small village in southern England

Why is Barton-on-sea vulnerable to coastal erosion

Its location on exposed cliffs:

Wave action

Wind

Rainfall

What is a result of coastal erosion at Barton-on-sea

Relatively rapid cliff retreat

How does climate change intensify the problem at Barton-on-sea

Rising sea levels and increased storm frequency increase energy of waves and likelihood of landslides

Social impacts at Barton-on-sea

Property damage

Declining property values

Potential relocation

Economic impacts at Barton-on-sea

Tourism affected:

Clifftop amenities

Beach access

Visitor attractions

May be lost

Environmental impacts at Barton-on-sea

Habitats destroyed

Cliffs destabilised

Landslides

Moves sediment along coast

Describe the cycle of decline at Barton-on-sea

Depopulation leads to

Reduced investment leads to

Increased risks leads to

Depopulation

Hard engineering strategies used at Barton-on-sea

Groynes

Sea walls

Revetments

Soft engineering strategies used at Barton-on-sea

Beach replenishment (sand is added to ↑size)

Managed retreat

St Lucia location

Small island country in Eastern Caribbean

Between Caribbean Sea and Atlantic Ocean

Main economic activity at St Lucia

Tourism:
Beaches

Resorts

Pitons

Climate change impacts on St Lucia

Increasing intensity of tropical storms & hurricanes:

Coastal flooding

Beach erosion

Damage to infrastructure

Socio-economic impacts of costal processes and tourism in St Lucia

Coastal communities face displacement (beach erosion)

Jobs affected (resorts damaged)

Environmental impacts of costal processes and tourism in St Lucia

Erosion & sea level rise:

Damage beaches & coral reefs

Disturb marine ecosystems

Increase sedimentation (↓attractiveness for visitors)

Hard engineering strategies at St Lucia

Seawalls

Groynes

Breakwaters

Soft engineering strategies at St Lucia

Beach nourishment

Coral reef restoration

Mangrove planting

Social strategies to reduce impacts at St Lucia

Setbacks from vulnerable coastlines

Sustainable building practices

Environmental education for visitors

Area Amazon Rainforest covers

5.5 million km²

Annual rainfall in Amazon Rainforest

2,000 - 3,000 mm

Average temp Amazon Rainforest

26 - 28 degrees celsius

What do the temp and rainfall in Amazon Rainforest create ideal temperatures for

Dense vegetation

High biodiversity

Complex ecosystems

What factors does the Amazon Rainforest contribute to

Global oxygen and carbon dioxide levels

Regional rainfall patterns

What human activities impact the Amazon Rainforest

Logging

Mining

Agriculture

→ Increased pressure on rainforest

Socio-economic impacts of rainforest use

Deforestation and road building displace indigenous populations and disrupt traditional lifestyles

Rainforest provides timber, minerals and land for agriculture

Supports local economies

Environmental impacts of rainforest use

Deforestation:

Loss of biodiversity

Soil erosion

Increased carbon emissions

Reduced rainfall

Initiatives around preserving Amazon Rainforest

Establishing protected areas and national parks

Enforcing sustainable logging practices

Promoting ecotourism

Monitoring deforestation with satellite technology

REDD+ → financial incentives for conservation

Location of Namib Desert

Stretches along Atlantic coast of southwestern Aftrica

Annual rainfall in Namib Desert

Often less than 50mm

Temperatures in Namib Desert

Can exceed 50 degrees Celsius in the summer

What causes frequent coastal fog in Namib Desert

Location alongside the cold Benguela Current

What resource does the coastal fog provide

Vital source of moisture for plants, animals and even local communities

Socio-economic challenges in the Namib Desert

Sparse human settlements due to:

Harsh living conditions

Water scarcity

Poor soils

Limits agricultural opportunities

Give an existing community in the Namib Desert and what they rely on to survive

Himba people rely on

Pastoralism

Small scale subsistence farming

Possible economic activities in the Namib Desert

Mining (diamonds and uranium)

Tourism (desert safaris)

(careful management required)

What is the fragile desert ecosystem in the Namib Desert vulnerable to

Overgrazing

Mining

Unregulated tourism

Factors threatening local biodiversity in Namib Desert

Water scarcity

Soil erosion

Habitat disruption

2 named examples of biodiversity in the Namib Desert

Welwitschia plant

Oryx

Water conservation techniques in Namib Desert

Fog harvesting

Dams

Careful irrigation

Things that help preserve biodiversity while supporting eco-tourism in Namib Desert

Protected areas such as Namib-Naukluft National Park