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geography- hazards - Coggle Diagram
geography- hazards
Plate tectonics
Core
- Liquid layer about 2260 km thick
-iron and nickel
- above inner core, below mantle
- 4400/6100c
- Inner core is a solid sphere 1216 km radius
Mantle
- Between crust and outer core
-silicate rocky shell
- 84% of earths volume
Crust
- Igneous, metamorphic and sedimentary rocks
- underlain by the mantle
- less than1% earths volume
- oceanic vs. continental crust
Key words
- primordial, exists at the beginning of time
- radiogenic, caused by radioactivity
- Lithosphere, consists of crust and upper mantle
- Asthenosphere, upper layer of earth's mantle below the lithosphere
- sea floor spreading, fresh areas of oceanic crust due to upwelling of magma
hazard management
The stages of hazard management
- identification of hazard
- analysis of the risk
- establishing priorities
- treating the risk
- implementing risk reduction plan
- public awareness
- community management strategy
- monitoring and reviewing system
Responses to disasters
- Federal Emergency Management agency FEMA designed to help those overwhelmed by disaster
- park model plots the impact of the natural disaster on quality of life over time
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Types of responses:
- prevention and modification (lessening likelihood of major event e.g., flood management and avalanche control); earthquake-proof buildings, houses on stilts, flood defenses
- modify vulnerability (predicting its occurrence eg. warning signs) planning laws, building design, prediction technology, aid provision, emergency services, communication and education.
- modify the loss (length of recovery process): speed of response, level of economic development, extent of damage done to infrastructure, morale, types of aid.
Case study: CALIFORNIA
California state hazard mitigation plan:
- land use planning
- building codes
- retrofitting
- removing structures from hazardous areas
Why is California a multi- hazard hotspot?
- 72 disasters required help from FEMA
- Lies on conservative plate boundary between American and Pacific tectonic plates
- San Andreas fault (produces earthquakes)
- landslides
- wildfire (35% pine forest)
- Most wildfire prone state in California
- Flash floods
- smog pollution
California wildfires
- California Fire Plan
- can use national guard
- defensible space for homeowners is an (100 ft) area clear of vegetation
- 2007 Californian wildfires
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