Evaluating critical links in early warning systems for natural hazards

Early warning systems (EWSs) are extensive systems that integrate different components of disaster risk reduction for the provision of timely warnings to minimize loss of life and to reduce economic and social impact on vulnerable populations. Historically, empirical research has focused on the individual components or sub-systems of EWSs, such as hazard monitoring, risk assessment, forecasting tools and warning dissemination. However, analyses of natural hazard disasters indicate that, in most cases, the processes that link individual components of EWS fail, rather than the components themselves. This paper reviews several case studies conducted over the last 40 years to present common emerging factors that improve links between the different components of EWSs. The identified factors include: (1) establishing effective communication networks to integrate scientific research into practice; (2) developing effective decision-making processes that incorporate local contexts by defining accountability and responsibility; (3) acknowledging the importance of risk perception and trust for an effective reaction; and (4) consideration of the differences among technocratic and participatory approaches in EWSs when applied in diverse contexts. These factors show the importance of flexibility and the consideration of local context in making EWSs effective, whereas increasing levels of standardization within EWSs nationally and globally might challenge the ability to incorporate the required local expertise and circumstances.