Distribution of tropical storms All occur between the Tropic of Cancer and the Tropic of Capricorn. All occur over warm oceans
Causes of Tropical storms Warm( over 27C) moist air rises from the surface of the sea. As it rises it meets cooler air and condenses to make clouds and rain. This condensation releases huge amounts of energy , producing strong winds. The winds are driven by the spin of the earth and go round and round. As the earth rotates the winds are sucked violently upwards in a vortex which can be 1,000km wide. Wind speeds can be as high as 200km per hour. These storms are fuelled by damp air when they reach land, dry air is being sucked up and they loose energy
Effects of Tropical storms Hurricane Katrina 28 August 2005 Primary Effects 1800 people died survivors had to swim for their lives many trapped on roofs. Levees breached in 20 places (80% of city flooded)2/3rds of cities flooding Roads damaged, Bridges collapsed- twin span bridge collapsed. Buildings destroyed Secondary Effects Oil spills Industrial waste and toxic chemicals in water Fall in trade business tourism Overall economic impact of Hurricane Katrina was estimated to be $ 150 billion Crime looting and racial tension
Effects of Cyclone Sidr 15 Nov. 2007 Primary Effects 3,447 deaths 34,500 injured 4 – 6.6 million affected People left homeless Tin roofs blown away Houses and schools demolished – 1.2 million homes destroyed Islands communication “snapped” 644,000 hectares of rice destroyed harvests of 23,000 hectares damaged Poultry, goats, cattle killed Washed away key production area for shrimp (second largest export) 90% of 5,000 shrimp farms destroyed 95% of crops destroyed in 11 districts Power lines destroyed Secondary Effects 360,000 still without shelter Many without electricity and short of food 3,000 fishermen reported missing Health problems due to contaminated water and shortage of drinking water Secondary 500 fishing boats destroyed debt Total damaged came to $ 450 million Mangrove forests destroyed will take up to 40 years to recover Crops of deer, tiger and other wildlife Tree damage.
Reducing the damaging effects of tropical storms. Monitoring how is the formation, progress , development and tracking of a tropical storm monitored? USE of GIS EDUCATION How do people prepare for a tropical storm in USA ? How do people prepare for a tropical storm in Bangladesh?
National Hurricane Center (Atlantic) Joint Typhoon warning system (Pacific) monitor the development and movement of a tropical storm.
Preparation Prepare Education programmes try to raise awareness how to prepare for and respond to a tropical storm. School lessons posters and leaflets. Family disaster plan. Emergency kit. Simple methods of protecting homes from strong winds and flying debris.
Prepare Materials tested in storm simulators. Windproof tiles water resistant windows. Strengthened building structures. Ground floor walls designed to “wash out “when a storm surges leaving only the supports . This allows the waves to wash through the building rather than destroy it.
LEDC Bangladesh can not afford the expensive equipment that the USA has. Building houses on stilts in case of a storm surge. Training local people to organise others in evacuation. Building shelter cyclones. Platforms within houses. Moving houses away from river banks. Training women what to wear in case they have to swim.