Image fromHumans are moving seaward (closer to the water) Ocean is moving landward Humans are moving seaward (closer to the water) Ocean is moving landward Coastal Processes LIDAR surveys - Dauphine Island, Gulf Coast of Alabama Landform changes caused by storm events Coastal Hazards Coastal areas Variable topography, climate, and vegetation Dynamic area Convergence of continental and oceanic processes Often populous (75% of US lives in coastal zone) Types of Hazards Tidal floods Tropical cyclones Tsunamis Coastal erosion Sea Level Rise From IPCC AR4 (2007), Physical Science Section, Chp. 5 Long term water level change Contributing factors: Melting of Earths ice volume Reconfiguration of Tectonic Plates Thermal Expansion of Seawater Scenario for WAIS melting Effects of Sea Level Rise Tides Daily water level change Storm Surge Episodic water level change Storm Surge Model Tropical Cyclones Coastal Hazards Tropical cyclones Originate near equator between 8N & 15S Typhoon (Pacific) and hurricane (Western Hemisphere) Effects High winds (> 75 mph or 120 km/hr) Flooding causes most life loss & damage Storm surge Heavy rains Tornadoes Results Deaths declining with improved warnings Property damage- $10 billion from Andrew Problems Increasing coastal population Poor evacuation routes Inadequate building codes/enforcement Wind Speed Distribution >100 km/hr over a region ~160 km in diameter >60 km/hr over a region ~640 km in diameter 160 km 640 km Frequency About 5 per year Greatest risk Florida Texas Three common tracks On-shore Gulf of Mexico East Coast skimmers Hurricane Strike Probability Map Tropical Storms Storm tracks generally fall into three categories: 1) Atlantic U-turns 2) Gulf coast strikers 3) East coast skirters 1999 Tropical Storms 1999 Tropical Storms Large Waves Data from Cape Canaveral Buoy and Model Results