Natural Hazards Flashcards
(22 cards)
What is a natural hazard
A natural event which threatens people or has the potential to cause damage, destruction or death
What is the hazard risk?
The chance/possibility that a natural hazard will take place
What are the 4 types of natural hazard?
1) tectonic
2) atmospheric
3) geomorphological
4) biological
Examples of tectonic hazards
Tsunamis, volcanic eruptions, earthquakes, etc.
Examples of atmospheric hazards
Tropical storms/hurricanes/typhoons, snow blizzard, heatwave, drought, etc.
Examples of geomorphological hazards
Sinkholes, avalanches, mudslides/rock falls/landslides, flooding, etc.
Example of biological hazards
Forest fires, diseases, swarms of locus
Factors affecting hazard risk
Geographical location Population density/distribution Time Natural factors(geology, relief, etc.) Frequency Magnitude Education levels Level of development/wealth
What is plate tectonics theory
The earths crust is divided in to several plates which slide along the mantle due to convection currents, and this explains mountains and ocean trenches
What is the global distribution bultion of earthquakes and volcanic eruptions
They are unevenly spread across the world, with high concentrations along many coastlines, where 2 plate margins meet
Constructive margin
2 plates moving apart, creates an ocean ridge and often volcanoes
Destructive margin
2 plates moving towards each other
1) ocean and continental-oceanic plate goes beneath the continental plate building friction which causes volcanoes and earthquakes
2) continental and continental-earthquakes and fold mountains as the rock crumples and it pushed up
Conservative margin
2 plates moving in opposite directions-causes lots of friction to build up and massive earthquakes
L’Aquila, Italy, 2009 earthquake(HIC) primary and secondary effects
Primary: -10 to 15 thousand buildings collapsed -308 people estimated to have died -1,500 people injured -67,500 made homeless -total damage:$11,434 million Secondary: -after shock caused landslides and damaged property -burst pipes caused land slides -number of students at the university plummeted -building prices shot up due to demand -city business area closed because deemed unsafe
L’Aquila, Italy, 2009(HIC) earthquake immediate and long term responses
Immediate:
-hotels provided shelter
-Italian Red Cross searched for survivors as well as providing blankets and food supplies
-mortgages and bills suspended
-declared a state of emergency and recieved $552 million from the EU
Long term:
-no taxes in 2010
-students given free public transportation, school supplies and no student fees for 3 years
-several years to rebuild (some historical sites expected to take 15 years)
Nepal, 2015(LIC) earthquake primary and secondary effects
Primary:
-total of 8,841 dead
-over 16,000 injured
-over 1 million made homeless
-historical building and temples damaged or collapsed
-26 hospitals and 50 % or schools collapsed
-reduced water and electricity supply
-352 after shocks and a 7.3 magnitude second earthquake
Secondary:
-triggered an avalanche on Everest, killing 19
-tourism(which is 8.9% of Nepal’s GDP) expected to shrink
-happened just before monsoon season…
-destroyed many rice storage, which 2/3 of the population depends on(mass food shortages)
Nepal, 2015(HIC) earthquake immediate and long term responses
Immediate
- requested international help, uk raised $126m by September 2015
- temporary shelter built, the red cross provided tents for 225,000 people
- the UN and world health organisation distributed medical supplies
- sherpas carried supplies to remote areas
- facebook launched a safety feature so people could indicate if they were safe
Long term
-government carried out a post-disaster assessment, reporting 25 areas requiring rebuilding
-over $274m for recovery 8 months after the earthquake
Durbar square heritage sites in June and everest in August reopened for tourist seasons
Location of Nepal earthquake
Gorkha district, north/central area of Nepal, 80km NW of the capital, Kath Mandu
Location of L’aquila earthquake
Central Italy, apennines mountains
Hurricane location
Northern hemisphere, america
Cyclone location
Southern hemisphere, Africa and Australia
Typhoon location
Northern hemisphere, Asia
