4. OBJECTIVES To define natural disaster To list down the four different types of natural disaster To explain the causes of an earthquake and tropical cyclone To list down the effects/problems causes by an earthquakes and tropical cyclone To describe measures to minimize the damages caused by an earthquake and tropical cyclone
5. Prior Knowledge The three layers of the Earth’s structure : core, mantle, and crust. The plates movements and its boundaries, and the distribution of the world's volcanic and earthquake areas. The students must have some background knowledge of the followings:
25. Tsumani Wave A tsunami wave flows toward the shore after a small earthquake in the Sunda Strait of Indonesia. Tsunamis are often mistakenly called tidal waves, but they are not caused by the gravitational forces involved in tides. Instead, tsunamis are believed to be caused by a tilting of the ocean floor, undersea landslides, or undersea volcanic eruptions
26. Effects and problems caused by an earthquake Each year about 500,00 earthquakes are recorded and of these about 1000 are strong enough to cause damage. As a result of these, roads and railways twist and buckle. Sewers, gas and water pipes and electricity cables break. Buildings crack and fall down. In the worst earthquakes, whole towns have been destroyed, and many people killed or injured.
32. TROPICAL CYCLONES What are tropical cyclones? Names given to tropical storms Where do tropical cyclone born? Case Study: Tropical cyclones in Bangladesh Tropical cyclone around the world How tropical cyclone is formed? How do tropical cyclone gains its energy?
44. Case Study: TROPICAL CYCLONES IN BANGLADESH How do tropical cyclone bring disaster to Bangladesh? 1991 Cyclone In Bangladesh How did the cyclone been spotted? The worst affected areas hits by the cyclone in Bangladesh Problems caused by tropical cyclone