L1 - Environmental Hazards Flashcards
What date was Tunguska?
30 June 1908
What were the effects of Tunguska?
- Set of Earthquake
- Flattened 2000km2 area
Define a hazard
Naturally occurring or human induced event or condition with the potential to create loss i.e. general source of danger
- Threat to people, goods or environment
- A potential threat to humans and their welfare (cause)
Three categories of hazard by how voluntary they are
- Natural
- Quasi-Natural
- Technological
Define a diaster
When a large number of people/goods/environment are killed, injured or killed by a hazardous event (community scale)
- The realisation of a hazard (actual consequence)
Give an example of a disaster
Aberfan Disaster, 1966, Wales
- Mining waste landslide
- Destroyed primary school
Define risk
Actual exposure of something of human value to a hazard
- Probability of hazard occurring & creating loss (likely consequence)
(Probability x Severity of Loss)
Three general types of hazard
- Natural Hazards
- Technological Hazards
- Context Hazards
Define a natural hazard
Extreme geophysical or biological events
Give four sub-types of natural hazard
- Geologic
- Atmospheric
- Hydrologic
- Biologic
Define a technological hazard
Major accidents
Give four sub-types of technological hazards
- Transport
- Industrial Hazards
- Unsafe public buildings
- Hazardous Materials
Define a context hazard
Global environmental change
Give four sub-types of context hazard
- International air pollution
- Environmental degradation
- Land pressure
- Super hazards
What is catastrophism?
Important change in physical landscape ascribed to catastrophic events
- Favoured historically for religious reasons
What is Diluviam and who thought there was a global layer of it from Noah’s flood?
- A layer of sediment left over from flooding
- D. Buckland
Who thought the Earth was 6000 years old
Archbishop Ussher, 1654
What is uniformitarianism?
Processes of erosion, lithification and uplift observed today have also occured in the past
- Supports Old Earth
What are Charles Lyells for principles of Geology?
- Superposition
- Original Horizontality
- Cross-cutting relationships
- Unconformities
Who pioneered uniformitarianism and uncomformities
James Hutton
What do unconformities suggest?
Cycles of erosion, transport, deposition and uplift
What are Charles Lyells two methodological laws of uniformitarianism?
- Uniformity of Law - Natural laws constant
- Uniformity of Process - If current processes can explain features, don’t invent new ones
What are Charles Lyells two substantive laws of uniformitarianism?
- Uniformity of rate - The pace of change is slow, steady and gradual
- Uniformity of state - Change is continuous but leads nowhere
What determines human sensitivity to hazards?
- Physical exposure
- Human vulnerability
Define Physical Exposure
Potentially damaging events at a specific location
Define Human Vulnerbility
Involves peoples capacities to avoid, resist or recover from harm
Give an example of an attempt to measure vulnerability.
What methodological problems are there?
- World Risk Index
- Difficult to collect data
