People-Centered Tsunami early Warning for the INdian coastlines (PCTWIN)

联合国呼吁地球上的每一个人都被预警系统覆盖。与其他更频繁的灾害相比，海啸事件造成的损失最大。印度的海岸线是世界上人口最多的地区之一，容易发生Makran、Sunda海沟北方和海底滑坡等俯冲带产生的海啸。这些活动的到达时间可能从安达曼尼科巴群岛的15分钟到大陆的2-3小时不等。这是一个时间尺度，有效的警告和准备采取行动可以挽救许多生命。印度海啸预警中心是印度洋沿岸沿着25个国家的官方海啸服务提供者。通过在地方参与的基础上提高海啸预警和预警中心的实际和业务能力，海啸预警和预警网络采取具体步骤，确保社区具有更强的抗灾能力，其目标与以人为本的预警支柱相一致：提高灾害风险知识;改进海啸的探测、观察和预报;更有效和更具包容性的海啸预警通信;加强防备：对海啸震源物理学的了解，可为了解未来大型逆冲断层地震的预期特征和频率提供宝贵的见解。太平洋海啸预警和信息网络将利用苏门答腊-安达曼区域的全球导航卫星系统台站，解决2004年苏门答腊大地震20年后与地震后变形和应变积累有关的基本问题，非地震和非典型海啸源是造成致命的近源海啸的原因，使受灾人口没有时间安全撤离。例如2018年苏拉威西海峡和巽他海峡海啸。PCTWIN通过对海啸成因海底滑坡源的综合表征，推动了前沿研究的边界。这将为海啸预报包括滑坡源铺平道路，海啸预报和预警方面存在若干业务和技术挑战，如早期源特征的高度不确定性，与及时同化和数据后处理有关的差距，以及不确定性的有效沟通。PCTWIN促进了模式的转变，从确定性到概率性的海啸预报，为印度下一代海啸预警系统建立灵活的情景。这就需要共同设计警报中不确定性的通报，并通过实时多通道数据同化，特别是通过实施大地测量数据，在5分钟内快速确定源的特征，减少不确定性。PCTWIN致力于在不同的尺度上预测海啸的危害和影响，从低分辨率的国家尺度到高分辨率的地方尺度，在选定的热点地区作为未来的试点。对情况的认识和对风险的认识方面的差距，特别是在纳入弱势群体方面的差距，严重阻碍了社区对海啸的复原力。PCTWIN采用包容性、地方性和参与性的方法，提高海啸风险社区的备灾能力。与教科文组织在印度洋地区的各项举措（如海啸应急识别方案）的协同作用促进了这一工作。太平洋海啸预警和应对网络补充了海啸预警和应对指标，引入了衡量当地社区制定的海啸应对计划的包容性和私营部门参与程度的指标，太平洋海啸预警和应对网络将共同设计和共同制定最佳做法准则，使社区做好海啸预警和抵御海啸的准备，努力使所有面临风险的社区都能做好海啸预警和应对海啸的准备。

The United Nations has called for every person on earth to be covered by warning systems. Tsunami events are responsible for greatest of losses compared to other more frequent hazards. The Indian coastlines, which are some of the most populated areas in the world, are prone to tsunamis generated from subduction zones such as Makran, the northern part of the Sunda trench and submarine landslides. The arrival time for these events could range between 15 minutes for the Andaman Nicobar Islands to 2-3 hours for the mainland. This is a time scale where effective warning and being prepared to act can save many lives. The Indian Tsunami Early Warning Centre (ITEWC) is an official tsunami service provider for 25 countries along the Indian Ocean Coasts. Through achieving improvements to the practical and operational capacities of ITEWC, grounded in local participation, PCTWIN takes concrete steps towards ensuring communities are more disaster resilient.The objectives of PCTWIN are aligned with the pillars of people-centred early warning: improving disaster risk knowledge; improved detection, observation, and forecasting of tsunamis; more effective and more inclusive tsunami warning communication; increased preparedness.Knowledge of the physics of tsunamigenic sources provides invaluable insights into the expected features and frequency of future large megathrust earthquakes. PCTWIN will use the GNSS stations in the Sumatra-Andaman region to tackle fundamental questions regarding post seismic deformation and strain accumulation 20 years after the great 2004 Sumatra Earthquake.Non-seismic and atypical tsunami sources have been responsible for deadly, near-source, tsunamis that have left no time for the affected populations to safely evacuate. Examples are the 2018 Sulawesi and Sunda Strait Tsunamis. PCTWIN pushes boundaries of frontier research by comprehensive characterization of tsunamigenic submarine landslide sources. This will pave the way for tsunami forecasting to include the landslide sources.There are several operational and technical challenges related to tsunami forecasting and early warning, such as high uncertainties in early source characterizations, gaps related to timely assimilation and post-processing of data, and effective communication of uncertainties. PCTWIN promotes a paradigm shift, from deterministic to probabilistic tsunami forecasting with flexible scenario building for the next generation of Indian tsunami early warning system. This entails co-design of communication of uncertainties in warnings and uncertainty reduction through real-time multi-channel data assimilation, especially through implementation of geodetic data for fast source characterization within 5 minutes. PCTWIN strives to forecast not only the hazard but also the impact, at different scales, from lower resolution national scale to higher resolution local scale at selected hotspots as pilot sites for the future.For near-source tsunamis with short arrival times, preparedness and readiness to act can save many lives. Situational awareness and risk perception gaps, especially related to inclusion of vulnerable groups, are serious barriers towards community resilience to tsunamis. PCTWIN embraces inclusive, local, and participatory methods for increasing the preparedness of the communities at tsunami risk. This is facilitated by synergies with UNESCO initiatives in the Indian Ocean region such as the Tsunami Ready Recognition Program. PCTWIN complements the Tsunami ready preparedness indicators by introducing markers measuring the inclusivity of the tsunami response plans devised by the local communities and engagement of the private sector.Striving to render tsunami readiness accessible to all communities at risk, PCTWIN will co-design and co-develop best practice guidelines for making communities tsunami ready and tsunami resilient.