naturaldisasters自然灾害PPT.ppt

THE DISASTERS OF WORLD NATURAL DISASTERS NATURAL DISASTER A natural disaster is the effect of a natural hazard like flood, tornado, hurricane, volcanic eruption or earthquake. FLOOD A flood is an overflow of water. The EU Floods directive defines a flood as a temporary covering by water of land not normally covered by water. Flooding may result from the volume of water within a body of water, such as a river, which overflows. TYPES OF FLOOD Riverine Estuarine Coastal Catastrophic Muddy DEADLIEST FLOODS Death Toll Event Location Date 2,500,000 – 3,700,000 China floods China 1931 900,000 – 2,000,000 Yellow River flood China 1887 500,000 – 700,000 Yellow River flood China 1938 TORNADO A tornado is a violent, dangerous, rotating column of air that is in contact with the surface of the earth and a cumulonimbus cloud. TYPES OF TORNADO Multiple vortex Waterspout Landspout DEADLIEST TORNADOES Death toll Event Location Date 1,300 The Daulatpur – Salturia Tornado Bangladesh 1989 923 East Pakistan Tornado Pakistan 1969 695 The Tri – State Tornado United States 1925 HURRICANE A hurricane is a tropical cyclone and the tropical cyclone is a storm system characterized by a large low – pressure center and numerous thunderstorms that produce strong winds and heavy rain. TYPES OF HURRICANES Tropical depression Tropical storm Typhoon DEADLIEST HURRICANES Death toll Event Location Date 500,000 Bhola cyclone Pakistan 1970 300,000 Indian cyclone India 1839 300,000 Calcutta cyclone India 1737 VOLCANIC ERUPTION During a volcanic eruption lava, tephra, and various gases are expelled from a volcanic vent or fissure. TYPES OF VOLCANIC ERUPTION Magmatic eruption Phreatomagmatic eruption Phreatic eruption DEADLIEST VOLCANIC ERUPTIONS Death toll Event Location Date 92,000 Mount Tambora Indonesia 1815 36,000 Krakatoa Indonesia 1883 33,000 Mount Vesuvius Italy 79 AD EARTHQUAKE An earthquake is the result of a sudden release of energy in the Earth’s crust that creates seismic waves. DEADLIEST EARTH