Tsunami Hazards: Public Awareness and Response in Sri Lanka

Abstract

The Indian Ocean Tsunami (IOT) in 2004 was one of the most destructive natural disasters in the region. The coastal regions of several countries bordering the Indian Ocean-Indonesia, Sri Lanka, India and Thailand-suffered severe loss of life and damage to properties. Although tsunamis have not been considered as a natural disaster in the past, the JOT and the subsequent tsunami alerts issued in 2005, 2007, 2010 and 2012 have highlighted exposure of Sri Lanka to such hazards. As Sri Lanka is most likely to be affected by far field tsunamis as opposed to near field tsunamis, one of the most effective countermeasures would be to implement an accurate early warning system together with an evacuation system to minimize adverse impacts. The effectiveness of an early warning and evacuation system would depend on the public awareness of possible hazards and associated responses to warnings issued. Thus, a survey was conducted to assess the public awareness on tsunamis and the response to tsunami warnings issued, which was conducted in the form of a questionnaire survey in the regions affected by the IOT. The preliminary analysis of the information gathered by the survey reveals that, although the majority of the public was not aware of tsunamis as a natural hazard prior to the JOT in 2004, a large majority is now well aware of such hazards. The importance of an early warning system in the country has also been identified and an Early Warning Centre has been established with the Department of Meteorology as the focal point which has now reached the capacity of issuing an early warning within 20 minutes of a possible tsunami generating event in the Indian Ocean. The analysis also reveals that there have been favourable responses to the warnings issued with the majority of the public receiving clear warnings, evacuating to safe locations well known within 30 minutes after receiving the warning. The results of the study thus clearly reveal the effectiveness of the tsunami early warning system and the evacuation system currently in place in the country.