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Natural Hazards. What are the greatest risks? Are these risks increasing? What are the costs associated with environmental hazards? Are the relative costs the same around the world? What controls these costs? How do we define risk?. So… What are common hazards.
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Natural Hazards • What are the greatest risks? • Are these risks increasing? • What are the costs associated with environmental hazards? • Are the relative costs the same around the world? • What controls these costs? • How do we define risk?
So… What are common hazards • Let’s list the hazards people think of when of when they think of natural hazards • Which of these are the most dangerous in the U.S.? • Which are the most expensive (in the U.S.)?
Data for U.S. ??? Data is a 150 year average from 19th and 20th centuries (Keller, 1999).
Number of Hazard Events World WideType of Hazard No of Events 9476 2389 1337 986 899 793 782 448 269 259 240 168 84 77 18 Tornadoes (U.S. only) Flood Tropical Cyclone Tsunami Earthquake Wind (other than tornado) Drought Landslide Wild fire Extreme temperature Temperate winter storm Volcano Tornadoes (non-US) Famine Storm surge For 20th century data from WHO (2002), U.S. tornado data are only for 1950-1995 for only F2-F5 size events
Numbers of Deaths Associated with Natural Disasters Worldwide Data for 20th century, based on WHO (2002) data.
Worldwide Hazard Ranking by CostType Cost Earthquake Flood Tropical storm Wind Storm Wild Fire Drought Cold wave Heat wave Total $248,624,900,000 $206,639,800,000 $80,077,700,000 $43,890,000,000 $20,212,800,000 $16,800,000,000 $9,555,000,000 $5,450,000,000 $631,250,200,000 Cost of natural hazards, summarized by type for top 100 most costly events of 20th century (WHO, 2002).
F5 Tornado that hit Greensburg Kansas, May 4, 2007 -Doppler radar gave a 20-minute warning -Tornado was 1.5 miles across at its base -95% of the town was leveled
Lightening strikes 100 times/second worldwide, with the greatest number of hits in central Africa. In the U.S. the greatest number of lightening strikes occur in Florida. The Empire State building is hit on average 100 times/year.
Define some terms • What are precursor events? • What is forecasting? • How do warnings work? • What is risk? • What is acceptable risk? • What is the purpose of insurance?