# Relationship between severity of a hazard, its probability and degree of risk For one case study hazard analyse the relationship between severity, probability,

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Relationship between severity of a hazard, its probability and degree of risk For one case study hazard analyse the relationship between severity, probability, and risk Find evidence to support this

Prediction All models built on a number of assumptions for variables: What would they be for earthquake? Tohoku – prediction of 99% probability that earthquake 7.5 would occur in next 75 yrs Defences built around this Models of plate tectonics assumed that there would not be simultaneous slips in faults Several incorrect assumptions based on historical observations

Why do hazard maps matter? Deciding how much of a country’s resources should be spent on mitigation Building tsunami defences large enough to withstand the 2011 event is too expensive Those built were able to withstand tsunamis experienced every 200-300 yrs

Cost vs mitigation Total cost of event / losses / defences Extent to which losses can be minimised (mitigation) A hazard model is crucial because it is used to predict the probabilities of tsunamis of different heights and hence the expected loss

Unzipping theory http://www.bbc.com/future/story/20120920-will-we-ever-predict- earthquakes http://www.bbc.com/future/story/20120920-will-we-ever-predict- earthquakes

How can EQ’s be predicted? Write notes on 2 methods used… http://science.howstuffworks.com/nature/natural- disasters/earthquake7.htm http://science.howstuffworks.com/nature/natural- disasters/earthquake7.htm http://www.livescience.com/6935-method-promises-earthquake- prediction.html http://www.livescience.com/6935-method-promises-earthquake- prediction.html

For your MEDC and LEDC EQ Case Studies… Had the earthquake been predicted? What degree of prediction had been given? What actions [if any] had been taken due to the predictions?

Hurricanes What are the methods used to predict hurricanes? (time, magnitude and location) How is this communicated to the public? What factors will affect predictions of the potential impacts? What are the limitations to these methods? HURRICANES / TYPHOONS http://www.hko.gov.hk/informtc/tcService.htm http://www.tropicalstormrisk.com/ http://www.nbcnews.com/id/9369041/ns/us_news- katrina_the_long_road_back/t/katrina-forecasters-were-remarkably- accurate/#.UaaYc0A0WuI http://www.sciencedaily.com/releases/2013/05/130524144951.htm#.UaVs0TfKM mg.twitter http://www.katrina.noaa.gov/forecast/forecast.html http://www.wunderground.com/tropical/ http://www.hko.gov.hk/informtc/tcService.htm http://www.tropicalstormrisk.com/ http://www.nbcnews.com/id/9369041/ns/us_news- katrina_the_long_road_back/t/katrina-forecasters-were-remarkably- accurate/#.UaaYc0A0WuI http://www.sciencedaily.com/releases/2013/05/130524144951.htm#.UaVs0TfKM mg.twitter http://www.katrina.noaa.gov/forecast/forecast.html http://www.wunderground.com/tropical/

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