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Tsunami and Coastal Disaster Risk Management in Indonesia

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Tsunami and Coastal Disaster Risk Management in Indonesia Taming the Impossible?! Tsunami and Coastal Disaster Risk Management in Indonesia - Training Module - by Eberhard Krain, Dewi Yanurita and Anne-Katrin Link Purwokerto 8th – 17th August 2006 Joint International Workshop cum Training Course “Coastal Ecosystems: Hazards Management and Rehabilitation” General Soedirman University (UNSOED), Purwokerto Centre for Science & Technology of the Non-Aligned and Other Development Countries (NAM-Centre), New Delhi, India Center for Tropical Marine Ecology (ZMT), Bremen List of Contents 1. INTRODUCTION ...................................................................................................... 4 2. CAUSES OF TSUNAMIS ......................................................................................... 4 3. PHYSICAL PROPERTIES OF TSUNAMI WAVES ................................................. 7 3.1 What is a Wave? ........................................................................................................................... 7 3.2 Tsunami Waves vs. Wind-generated Waves ............................................................................. 10 3.3 Energy Transformation .............................................................................................................. 12 3.4 Deep-water vs. Shallow-water Waves ....................................................................................... 12 3.5 Definition of Shore Face Border ................................................................................................ 15 3.6 Wave Refraction .......................................................................................................................... 16 4. CHARACTERISTICS AND DIMENSIONS OF TSUNAMIS .................................. 18 4.1 Tsunami Trough and Crest ........................................................................................................ 18 4.2 How Many Tsunami Waves Are Common? ............................................................................... 19 4.3 Size of Tsunamis......................................................................................................................... 20 4.4 Where do Tsunamis Occur? ...................................................................................................... 20 5. THE TSUNAMI EARLY WARNING SYSTEMS (TEWS) ....................................... 22 5.1 Pacific Tsunami Warning Center (PTWC) ................................................................................. 22 5.2 Deep-ocean Tsunami Detection ................................................................................................. 23 5.3 The German-Indian Ocean Tsunami Early Warning System (GITEWS) .................................. 24 6. WHAT TO DO IF A TSUNAMI IS APPROACHING (SOURCE: NASA OBSERVATORIUM (1999)) ....................................................................................... 26 7. NATURAL BUFFERS FOR COASTLINES ........................................................... 26 1 7.1 Coral Reefs .................................................................................................................................. 26 7.2 Mangroves ................................................................................................................................... 27 7.3 Coastal Terrestrial Vegetation ................................................................................................... 27 8. DISASTER MANAGEMENT IN INDONESIA ........................................................ 27 8.2 Institutional Framework for Natural Disaster Management in Indonesia ............................... 28 8.2.1 Decentralization Laws and Handling of Disasters .................................................................. 28 8.2.2 Disaster Risk Management on National Level ....................................................................... 28 8.2.3 Disaster Risk Management on Regional and Local Level ...................................................... 29 8.2.4 Problems in Disaster Risk Management ................................................................................ 29 8.3 The Relationship Between Coastal Disaster Risk Management and Integrated Coastal Zone Management ...................................................................................................................................... 29 8.4 People‘s Attitude......................................................................................................................... 31 9. CONCLUSIONS ..................................................................................................... 32 10. GLOSSARY (SOURCE: NOAA/PMEL (2006)) ................................................... 34 11. SELECTED READINGS AND REFERENCES .................................................... 38 12. ANNEX: ANSWERS TO QUESTIONS ................................................................ 41 2 List of Figures FIGURE 1A -1C) TSUNAMI GENERATION ......................................................................................................... 5 FIGURE 2A) WAVE PROPERTIES: WAVE PARAMETERS. ............................................................................. 7 FIGURE 3) THE FAMOUS KRAKATAU ERUPTION IN 1883: WAVE HEIGHT IN METERS AND RUN TIME OF THE TSUNAMI IN MINUTES. SOURCE: NIEDEK AND FRATER (2004:22). ...................... 9 FIGURE 4) MAP VIEW AND WAVE PROFILE OF WIND-GENERATED WAVES. SOURCE: PINET (1998:239) ....................................................................................................................................................... 10 FIGURE 5A) WAVE TRAINS: MERGING OF 2 WAVE TRAINS. SOURCE: SCHWARZER (2006) ........... 11 FIGURE 6) WAVE ENERGY TRANSFORMATION AT THE SHORELINE, SOURCE SCHWARZER (2006). ......................................................................................................................................................................... 12 FIGURE 7A) THE MOTION OF WATER PARTICLES BENEATH WAVES. WAVE MOTION WITH DEPTH ............................................................................................................................................................ 13 FIGURE 8A) THE DISTORTION OF WATER-PARTICLES ORBITS IN SHALLOW WATER. DEEP- WATER WAVE ............................................................................................................................................. 14 FIGURE 9) THE SHORE FACE DEFINITION ..................................................................................................... 15 FIGURE 10A) WAVE REFRACTION IN SHALLOW WATER. CHANGE IN WAVE DIRECTION IN SHALLOW WATER. SOURCE: SCHWARZER (2006) ............................................................................ 16 FIGURE 11A) WAVE REFRACTION AT THE SHORELINE. WAVE REFRACTION IN BAYS. SOURCE: SCHWARZER (2006) .................................................................................................................................... 17 FIGURE 12) MODEL OF WAVE CREST (RED) AND THROUGH (BLUE) OF THE INDIAN OCEAN TSUNAMI. SOURCE: RESEARCH CENTER FOR DISASTER REDUCTION SYSTEMS (2005) ....... 19 FIGURE 13) TSUNAMI THREATENED COASTLINES OF THE WORLD. SOURCE NIEDEK AND FRATER (2004:20). ....................................................................................................................................... 21 FIGURE 14) TSUNAMI HAZARD MAP OF THE WORLD. SOURCE:OAK RIDGE NATIONAL LABORATORY IN NATIONAL GEOGRAPHIC (APRIL 2005) [INDONESIAN VERSION OF THE NATIONAL GEOGRAPHIC]. ...................................................................................................................... 22 FIGURE 15) THE PACIFIC TSUNAMI WARNING CENTER (PTWC). SOURCE NIEDEK AND FRATER (2004:25) ......................................................................................................................................................... 23 FIGURE 16) THE DEEP-OCEAN ASSESSMENT AND REPORTING OF TSUNAMIS (DART) SYSTEM. SOURCE: NOAA (N.P.) ................................................................................................................................ 24 FIGURE 17) THE GERMAN INDIAN OCEAN TSUNAMI EARLY WARNING SYSTEM (GITEWS) AS PLANNED BY THE GFZ, SHOWING THE LOCATION OF THE PLANNED BUOY SYSTEMS, TERRESTRIAL AND COASTAL TIDE STATIONS. SOURCE: GEOFORSCHUNGSZENTRUM POTSDAM, WESER KURIER (2006). ......................................................................................................... 25 FIGURE 18) ACTIVE AND POTENTIALLY ACTIVE VOLCANOES IN INDONESIA. SOURCE: EFFENDI ET.AL. (2004:7).............................................................................................................................................. 27 FIGURE 19) CONEPTUAL VIEW OF THE GEOHAZARD SYSTEM. SOURCE: EFFENDI ET.AL. (2004:9) ......................................................................................................................................................................... 28 List of Tables TABLE 1: DIFFERENT MANAGEMENT STYLES BY DISASTER PHASES 31 3 1. Introduction Natural extreme events, such as floods, earthquakes or storms, can cause much damage to people, property, and nature. During the 26th December 2004 Tsunami off the coast of northern Sumatra, Indonesia, many coastal communities along the shores of the Indian Ocean were affected. In Indonesia more than 230,000 people died or remained missing and hundred thousands lost their homes. This reader will explain and summarize the physical characteristics of tsunamis and reflect the current
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