A global review of disaster reduction initiatives - Welcome to the ...

early warning reducing the consequences andespecially the human losses from natural disasters.To give but a few examples, forecast timeand location of landfall of tropical cyclones isnow 48 hours in advance; the warning time oftornadoes has doubled in one decade; andwarnings of drought are now issued severalmonths in advance. The development of newinformation technologies and the very rapidspread of global communications have considerablyincreased the availability of informationand early warnings about natural disasters.These technological advances now enable bettermonitoring, prediction and forecasting ofextreme weather conditions. Significantimprovements in global observation systemshave also enhanced the early detection of medium-termabnormal climatic conditions such asEl Niño events, and will contribute to warningsof long-term hazards associated with environmentalchange. Sophisticated early warningsystems can only become effective with the freeand unrestricted exchange of meteorologicaldata throughout and among societies, and withsimilar attention given to the expression ofwarnings so that the people for whom they areintended can understand them.However, the ability to deliver this vital informationto the public in the locations where it ismost likely to be affected by disasters has notalways enjoyed similar success. Local mechanismsfor communicating risk, or downscalingthe interpretation of alerts to relate to local conditionsor experience, remain very weak inmany cases. Sophistication has to be weighedagainst local capacities, needs, resources andtraditions. Moreover, information about theadverse impacts of disasters on people andinfrastructure (i.e. vulnerability and riskassessments) that is necessary for informeddecision-making is often missing. Even whereabilities and procedures do exist, communitiesdo not often respond appropriately to them,because there is a lack of planning, resources orviable protective options that they could utilizein a timely manner. Ironically, in many documentedcases, the perceived threat of losingtheir property to looters when unprotected duringa time of evacuation, is considered a greaterthreat by many people than a loss caused by asevere weather disaster.Elements for effective early warning are welldocumented. Guiding principles for effectiveSelected application of disaster reduction measuresearly warning resulted from several years ofwork undertaken under the aegis of theIDNDR Early Warning Programme, byexperts associated with all aspects of warningpractices and for various types of hazards. Thedifferent sets of these guiding principles arereproduced throughout this chapter as theystill provide a clear and comprehensive basisfor the early warning process. The challenge tobe met in the coming years is to translate theseaccepted principles into concrete action-orientedmodalities.By way of introduction to the specific issues ofconcern to improve the effectiveness of earlywarning, the Mount Pinatubo example illustratesthe added value of early warning systemsand describes the factors that contribute to theeffective warning of populations at risk.Early warning for the 1991 eruptions of the Pinatubo volcano,the Philippines: a success storyEarly warning for the 1991 eruptions of the Pinatubo volcanois a success story in that the number of deaths compared tothat of those at risk was small despite the magnitude and violenceof the eruption. The success was due to a number offactors that illustrate the important issues in this chapter: timelyidentification of the hazard and delineation of vulnerableareas, successful application of state-of-the-art monitoring andsurveillance techniques, accurate prediction of the destructivephases, timely issuance and dissemination of easily understoodwarnings, prompt action of key civil defence officials and disasterresponse workers, and timely evacuation of majority ofinhabitants at risk.The positive aspects of the experience highlighted the value ofthe following: state-of-the-art monitoring equipment and techniques,international cooperation based on mutual respect, sustainedintensive public education, active involvement of selectedscientists as spokespersons for awareness and disseminationpurposes, open and speedy communication lines between sciencepeople and civil defence officials, good relationshipbetween scientists and the media adapted fromPunongbayan and Newhall, 1998Early warning is not a technical and even less atechnological issue, but a human and organizationalone. Satellite coverage and state-of-theartsurveillance techniques are now sufficientand the most difficult part, which is composedof the following requisites, remains to be tackled.2635