Awareness of tsunami natural warning signs and intended evacuation behaviors in Java, Indonesia

The south coast of Java has a long history of deadly seismogenic tsunamis. The most recent tsunami events in 1994 and 2006 killed hundreds due to lack of awareness and implementation of disaster mitigation strategies. Community-based tsunami hazard education programs founded on observation of natural warning signs and self-evacuation are critical to saving lives. Students at middle and high schools in three cities along the southern coast of Java (N = 887) participated in a pen/paper survey that included critical awareness, risk perception, self-efficacy, response efficacy, evacuation intentions, past participation in evacuation simulations, communication channels, and warning preferences. Participants generally had high perceived tsunami risk and efficacy. Overall, participants who associated tsunamis with earthquakes know that a receding ocean is a sign of an impending tsunami and believed that vertical evacuation was more important than inland evacuation. School, Internet, and social media were most often reported as information sources. However, the majority of participants believed that an earthquake had to be dramatic to cause a tsunami. Participants overestimated both the duration of ground shaking prior to a tsunami event and the suggested evacuation window. Differences between cities were found for evacuation simulation history and personal experience with tsunamis; however, neither increased critical awareness. Evacuation simulations, coupled with education of under what circumstances to evacuate (20/20/20 principle), should be implemented throughout Java. Short messages stressing that even weak earthquakes can cause tsunamis should be communicated through a variety of channels such as TV, radio, Internet, and social media.

The south coast of Java has a long history of deadly seismogenic tsunamis. The most recent tsunami events in 1994 and 2006 killed hundreds due to lack of awareness and implementation of disaster mitigation strategies. Community-based tsunami hazard education programs founded on observation of natural warning signs and self-evacuation are critical to saving lives. Students at middle and high schools in three cities along the southern coast of Java (N = 887) participated in a pen/paper survey that included critical awareness, risk perception, self-efficacy, response efficacy, evacuation intentions, past participation in evacuation simulations, communication channels, and warning preferences. Participants generally had high perceived tsunami risk and efficacy. Overall, participants who associated tsunamis with earthquakes know that a receding ocean is a sign of an impending tsunami and believed that vertical evacuation was more important than inland evacuation. School, Internet, and social media were most often reported as information sources. However, the majority of participants believed that an earthquake had to be dramatic to cause a tsunami. Participants overestimated both the duration of ground shaking prior to a tsunami event and the suggested evacuation window. Differences between cities were found for evacuation simulation history and personal experience with tsunamis; however, neither increased critical awareness. Evacuation simulations, coupled with education of under what circumstances to evacuate (20/20/20 principle), should be implemented throughout Java. Short messages stressing that even weak earthquakes can cause tsunamis should be communicated through a variety of channels such as TV, radio, Internet, and social media.