• Plans and procedures for tsunami warning and emergency management.

      Intergovernmental Oceanographic Commission (UNESCO-IOCParis, France, 2017)
      This manual seeks to assist countries participating in the IOC-coordinated regional Tsunami Warning and Mitigation Systems in strengthening their existing tsunami warning and emergency responses through the development of Tsunami Warning and Emergency Response Plans and Standard Operating Procedures (SOPs). It relates to tsunami warning authorities (referred to as National Tsunami Warning Centres - NTWCs) and to tsunami emergency management authorities (referred to as Emergency Management Agencies - EMAs), promoting alignment, interoperability and consistency among all stakeholders in the end-to-end tsunami warning system. The Tsunami Warning System (TWS) An end-to-end Tsunami Warning System (TWS) includes the following components: - Knowledge of the hazards and risks to coastal communities from tsunamis and planning for their potential impact - Access to information from the ICG Tsunami Service Providers and/or National Tsunami Warning Centres on the earthquake characteristics, a tsunami assessment and forecast, and tsunami observations - Capability to evaluate the information received in order to determine the threat to their communities - Ability to quickly disseminate and communicate clear, understandable, and actionable warnings to prepared coastal communities in advance of the oncoming tsunami; and - Capacities at national, local and community levels for effective tsunami emergency response. A TWS is best defined in an end-to-end National Tsunami Warning and Emergency Response Plan, with a minimum requirement being the existence of such a document approved at the national level. The main purpose of this guideline is to describe the collective components of the TWS and the allocation (and description) of responsibilities and actions for each component, then designating relevant authorities for each action. The plan may also contain the concepts, thresholds, target times, systems, procedures, and templates used in the tsunami warning chain and a concise description of the tsunami threat for the country (or reference to the relevant documents). In some countries this Plan may need to be split into two plans, a National Tsunami Warning Plan and a Tsunami Emergency Response (TER) Plan, to recognise different functions and responsibilities. In either respect, the overall content and end-to-end processes should be complementary. This guideline describes the TWS and its supporting documents, with a specific focus on tsunami warning plans and SOPs for tsunami warning authorities and emergency response plans and SOPs for key responding agencies. Tsunami warning The NTWC provides warnings of potentially dangerous tsunamis to EMAs and in many cases direct to the communities of the sovereign nation in which it resides and which it serves. It operates on a 24/7 basis to receive earthquake and tsunami information from ICG Tsunami Service Providers (TSPs) of its choice, evaluates the information in terms of the tsunami threat to the country’s coastal communities, and issues warnings about threats. Each country formally nominates a Tsunami Warning Focal Point (TWFP) to the IOC for receipt and national management of tsunami threat information received from TSPs. Some countries have established their own NTWC as the national tsunami warning authority, which have the independent capacity to continuously monitor seismicity in real-time using local and global seismographic networks to locate and determine the magnitude of potentially tsunamigenic earthquakes. This capacity allows them to assess the threat of a tsunami empirically (based mainly on the earthquake magnitude) or through tsunami modelling in the same manner as done by a TSP. Such national assessments may be shared with the TSPs and the NTWCs of other countries. Whether a NTWC has its own in-house seismic processing facility and tsunami monitoring and assessment capability, or whether it relies on the seismic and tsunami threat information contained in notifications from TSPs (and other NTWCs), the next steps are common to all NTWCs. These are the formulation and dissemination of official national warnings to the EMA and other recipients in accordance with the National Tsunami Warning and Emergency Response Plan. A NTWC must respond quickly, be as accurate as possible, and be reliable in order to be effective. In order to achieve this, an NTWC should have regularly exercised and tested SOPs in place for efficiently receiving the earthquake and tsunami information from TSPs (and other NTWCs), or generated by themselves, evaluate and assess the threat to their country before issuing clearly understood threat alerts to national authorities responsible for emergency management and public safety. In some cases NTWCs may issue warnings directly to the public and media, but still in consultation with EMA. This guideline describes the essential functions of a NTWC and the relationship of an NTWC to ICG Tsunami Service Providers (TSPs) and other NTWCs. It is supported by Annexes containing more detail and examples. Tsunami emergency response In association with other authorities, government agencies, and community groups, EMAs must establish and maintain preparedness for an effective tsunami response through hazard risk assessment and the establishment of emergency response plans and accompanying procedures that focus on public awareness, public alerting, and evacuations. These plans and procedures must acknowledge that notifications from a NTWC may provide little response time – a tsunami generated by a local earthquake may impact within minutes, and they can occur at any time of the day or night. In such cases, natural warning signs (e.g. unexpected sudden drop in sea level indicating the pending arrival of the tsunami crest, although not always the case) may be able to provide much more timely warnings than waiting for the seismic information to feasibly reach the sensors, be analysed and tsunami forecasts and warnings generated and issued. During tsunami events EMAs must immediately interpret the warnings issued by the NTWC, and then decide on the appropriate response actions. Accordingly, they must also operate on a 24/7 basis in order to disseminate warnings (if required), instructions and other safety information to agencies at all applicable levels of government, threatened communities, and the media, in accordance with the National Tsunami Warning and Emergency Response Plan. They are also responsible for informing the public of the “All Clear” when the threat is over. Through the activation of Emergency Operations Centres (EOCs) at the respective levels of government, EMAs must coordinate an appropriate emergency response amongst all participating agencies. This guideline covers the linkage between the NTWC and the EMA with a description of the procedures to be adopted by the latter as recipients or potential recipients of warnings from their NTWC, and their subsequent response actions. It is supported by Annexes containing more detail and examples.