EQ3 Tectonics Flashcards
(47 cards)
how have natural events changed over the years?
generally increased from 38 in1980 to 98 in 2010- especially meteorological and hydrological
geophysical events not changing much
why are we recording more natural events?
better monitoring and recording of events
global popn increase so more people effected and living in risk areas
what was the population in 1975 compared to now?
1975- 4 Bn
now- 8.2 billion people
how has number of deaths changed since 1975
120,000 in 1975
85000 in 2023
why is the number of deaths attributed to natural disasters decreasing
better warning systems
improved buildings
why are disaster statistics hard to use?
depends on whether primary AND secondary deaths are included
regional events in remote places often under-recorded
declaration of deaths could be subject to political bias
hard to analyse time trends from historical data
what is a megadisaster
an unexpected natural or manmade catastrophe of exceptional magnitude or causing unusually severe or unprecedented damage on a regional or global scale
key characteristics of megadisasters
large scale (aerial/ spatial or economic and human impact)
scale causes serious problems for effective management to minimise impact
require international support - on a regional or global level
affect more than one country directly or indirectly
What is a multiple hazard zone
Places where a number of physical hazards combine and create an increased level of risk for the country and its population
Often made worse by a vulnerable population or suffers repeated events
What is a disaster hotspot
A place where a vulnerable population suffers repeated events
What is a hydrometeorological hazard
Natural hazards caused by climate processes eg droughts, floods, hurricanes, storms
Which 3 countries have highest risk of mortality from multiple hazards
Taiwan
El Salvador
Costa rica
Which 3 countries have highest risk of economic loss
Taiwan
Dominican Republic
Jamaica
Where are disaster hotspots most likely to be
Where plate boundaries intersect with major storm belts in high areas of human concentration in LICs
What priorities might countries have before risk management of multiple hazards?
Poverty
Fighting HIV/AIDS
Not able to afford tech to cope with multiple hazards
What is earthquake risk forecast based on
Statistical likelihood based on :
Seismic monitoring networks
Historical records
What are the challenges of predicting earthquakes
Not possible to make accurate predictions of when and where
Forecasting only reliable in the long term instead of short term
Why is forecasting of earthquakes important
Not possible to predict accurately
Encourages government to enforce better building regulations or improved evacuate procedures
How many volcanoes since 1980 have caused more than 1000 deaths
2
How are volcanoes monitored and predicted
Ground deformation measured
Ground vibrations
Cameras observe physical changes
Thermal imaging
Monitoring airborne gas changes
What physical factors impact response to a hazard
Accessibility of region
Type and scale of hazard
Topography of region - mountains
Climate - rain can cause access problems
What human factors can affect response
Population density
Degree of community preparedness
Technical engineering and resources
Education and training
Economic wealth of a country
Social and political framework
Government competence and resources
What is the hazard management cycle
Hazard > emergency > recovery > reconstruction > disaster free period
Repeat
What are some examples of mitigation for a hazard
Zoning and land use planning
Developing and enforcing building code
Building protective structures (tsunami sea wall defence)
