Transcript Chapter 29
Chapter 16 Natural Disasters and Catastrophes Hazards, Disasters, and Catastrophes • The Most Devastating Natural Hazards -Earthquake -Tsunami -Volcanic Eruption -Wildfire -Landslides -Tornado -Hurricane -Flood -Heatwave -Drought Hazards, Disasters, and Catastrophes • Natural Hazards – Any natural process that is a potential threat to human life and property • Disasters – A hazardous event that occurs over a limited time span in a defined geographic area where the loss of human life and property is significant. • Catastrophes – A massive disaster requiring significant time and money for recovery. Disasters and Catastrophes: Taking a Historic Point of View • Natural Hazards are Repetitive Events • Study History to reduce hazards • Link prehistoric record with historic record and modern measurements to gain insights. Fundamental Concepts • Natural processes have service functions. • Hazards are predictable • Hazards are producing more catastrophes than they were before. • Risk from hazards can be estimated • Adverse effects of hazards can be minimized Natural Processes Have Natural Service Functions • Physical processes create a varied landscape. • Periodic disturbance such as earthquake, volcanic eruption, and flooding create: – – – – Fertile soil Available water Diverse land and life Aesthetic beauty Lava Delta at E. Lae Apunki Hazards Are Predictable • Monitor areas where hazards have occurred in the past. • Statistics can evaluate frequency of a particular event. • Predict based on geography of where hazards are most likely to occur. Ex. Earthquakes most like near coastlines. • Forecast events and issue warnings. Ex. Tsunami warning system in the Pacific Ocean. Tsunami Warning System Linkages Exist Between Hazards and the Environment • Often one hazard can create another. Ex. Volcanic eruption can cause a landslide. • Natural hazards are linked to earth materials. Ex. Weak soils can lead to landslides. • Hazards can cause the disruption of ecosystems. Volcanic eruptions can cause mudslides Hazards are Producing More Catastrophes • Key Factor: Human Population Growth – Humans pushed into more hazardous areas – 15 cities of over 10 million most vulnerable • Land use transformation – How we use land effects hazardous events – Ex. Flooding of Yangtze River Risk From Hazards can be Estimated • Risk: product of the probability of an event times the consequences • Acceptable Risk: Risks that individuals or society are willing to take. Adverse Effects of Hazards can be Minimized • Active vs. Reactive Response: – – – – – Need to be more active Land use planning Hazard-resistant construction Protection of ecosystems Evacuation plans What Does the Future Hold? • Major Disasters are increasing due to population pressure and poor land-use planning. • Anticipating hazards will minimize suffering and economic losses