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Physical and human geography. Natural hazards. CHALLENGES FOR HUMAN ACTIVITIES. NATURAL HAZARD IS A NATURAL EVENT THAT CAUSES DAMAGE TO PROPERTY, DISRUPTION TO NORMAL LIFE AND MAY CAUSE LOSS OF LIFE. CAUSED BY IMPACT OF NATURAL EVENTS ON SOCIAL AND ECONOMIC DEVELOPMENT. NATURAL HAZARD.
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Natural hazards • CHALLENGES FOR HUMAN ACTIVITIES. • NATURAL HAZARD IS A NATURAL EVENT THAT CAUSES DAMAGE TO PROPERTY, DISRUPTION TO NORMAL LIFE AND MAY CAUSE LOSS OF LIFE. • CAUSED BY IMPACT OF NATURAL EVENTS ON SOCIAL AND ECONOMIC DEVELOPMENT.
NATURAL HAZARD • RAPID INCREASE IN POPULATION • URBANISATION (Including shanty towns) • CHANGING LAND USE IN RURAL AREAS • NUMBER OF PEOPLE IN POVERTY • CHANGING NATURAL ENVIRONMENT
TECTONIC HAZARDS • CAUSED BY PLATE MOVEMENT
Tropical storms • WINDS, FLOODS AND STORM SURGES. • HURRICANES ARE KNOWN AS TROPICAL CYCLONES.
Tropical storms • Tropical cyclones are like giant engines that use warm, moist air as fuel. That is why they form only over warm ocean waters near the equator. The warm, moist air over the ocean rises upward from near the surface. Because this air moves up and away from the surface, there is less air left near the surface. • Air from surrounding areas with higher air pressure pushes in to the low pressure area. Then that "new" air becomes warm and moist and rises, too. As the warm air continues to rise, the surrounding air swirls in to take its place. As the warmed, moist air rises and cools off, the water in the air forms clouds. The whole system of clouds and wind spins and grows, fed by the ocean's heat and water evaporating from the surface
floods • RESULT OF TROPICAL STORMS • CONTINUOS RAIN • LOCATION OF SETTLEMENT • COASTAL FLOODING. HIGH TIDAL RANGE.
FLOODS • BANGLADESH
FLOODS IN BANGLADESH • 3 LARGE RIVERS: • GANGES, BRAHMAPUTRA AND MEGHNA. • MONSOON RAINS • AVERAGE OF 16 CYCLONES PER YEAR • 80% OF POPULATION LIVE IN RURAL AREAS • HIGHEST RAINFALL TOTALS IN THE WORLD • POPULATION GROWTH AND RURAL IMPOVERISHMENT
drought • EXTENDED PERIOD OF DRY WEATHER LEADING TO CONDITIONS OF EXTREME DRYNESS. • ABSOLUT DROUGHT: 15 CONSECUTIVE DAYS WITH LESS THAN 0.2 MM OF RAINFALL. • PARTIAL DROUGHT: 29 CONSECUTIVE DAYS WHERE AVERAGE DAILY RAINFALL DOES NOT EXCEED 0.2 MM. • FOREST FIRES • FOOD SHORTAGES
rainforest • OPPORTUNITIES: FARMING HYDRO-ELECTRIC POWER TOURISM FISHING MINERAL DEVELOPMENT
RAINFOREST • HAZARDS: SURFACE EROSION SANDIFICATION CLIMATIC CHANGE LOSS OF BIODIVERSITY
deserts • HAZARDS: WEATHERING FLOODING EROSION LANDSLIDES AND ROCKFALLS DUST STORMS