Japan Tsunami Urgency Response

日本海啸紧急响应

• 批准号: NE/J006122/1
• 负责人: David Tappin
• 金额: $ 5.61万
• 依托单位: British Geological Survey
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FJ006122%2F1
• 关键词: Japan; Tsunami; Urgency; Response

At 1446 (local time Japan) on the 11th March 2011, off the east coast of Honshu Island, Japan, an earthquake of Magnitude 9.0 generated a tsunami that inundated a 400 kilometre length of the adjacent coastline. The tsunami was up to 17 metres high, it surmounted many of the protective walls constructed to protect the coastal areas and at least 27,000 people died and over 350,000 people were made homeless. This is on a scale similar to that of the 2004 Indian Ocean event.Small tsunamis in this earthquake-prone /tectonically active region are not unusual, but ones of this magnitude are rare, the last event of significant size was in 1896, when 27,000 people perished. After relief operations, it is essential for scientists to visit the affected area to acquire data on the tsunami impact including inundation, runup, flow depth and erosion. Much of the evidence on the tsunami is fragile and quickly eroded or removed. The orientation of a tsunami may be identified by the orientations of grass, tsunami height may be seen from water marks on buildings or building damage; debris caught in trees or bushes is common. After a tsunami, survivors are anxious to clean up, to wash the evidence away and to get their lives back to normal. Natural processes-rain, wind, surf-also degrade the evidence of a tsunami. Since much evidence is ephemeral, not only are scientists eager to make observations quickly, too many rapid response and preliminary surveys end up being the only surveys conducted. The surveys objectives are to better understand the tsunami, its relationship to the source mechanisms (in this case the earthquake) and prepare improved mitigation strategies for use in the future. Now, for the first time, tsunami scientists have been invited into the devastated areas and the task they face is enormous. There are limited numbers of appropriately skilled people and the scale of the devastation huge - probably thousands of square kilometres in area. To acquire data over this area is going to be challenging at best, thus international scientists from outside Japan have been invited into the country to research the tsunami; there has been a significant delay to allow relief operations to proceed, so it is essential now to respond immediately, the PI of the proposal Professor David Tappin is one of the invited scientists. In addition, new methodologies are required to better cope with the scale of the event.To address the need, here we propose to visit the area of tsunami inundation to collect data on tsunami deposits and tsunami impact. In addition we will develop an integrated methodology with desk-based mapping of the inundated area prior to acquiring the field data that will be followed by fieldwork. Thus the field work will be a validation of prior interpretations. Significantly, for the first time after a tsunami, high resolution satellite imagery has been released on humanitarian grounds to assist relief workers and scientists working on mitigation. Not only will the interpretation of the satellite images guide the field operations, but the images and interpretations will be uploaded onto field mapping computers. The desk-based interpretations will then be amended and improved by the digital acquisition of field data on tsunami inundation, flow directions, the location of areas of erosion and sedimentation, together with various aspects of the coast that will allow a better understanding of how the tsunami inundation took place. Downstream these data will be uploaded onto a GIS modelled with digital terrain models to allow the identification of areas of safety where people can escape to in future events. Mapping areas of inundation will also lead to better models of tsunami run up. Investigations of the tsunami sediments will result in better discrimination of past tsunami events and improved risk strategies.

2011年3月11日14时46分（日本当地时间），日本本州岛东海岸附近发生9.0级地震，引发海啸，淹没了400公里长的邻近海岸线。海啸高达17米，冲垮了为保护沿海地区而建造的许多防护墙，至少有27 000人死亡，350 000多人无家可归。在这个地震多发/构造活跃的地区，小型海啸并不罕见，但这种规模的海啸是罕见的，上一次大规模的海啸发生在1896年，当时有27，000人丧生。在救灾行动之后，科学家必须访问受灾地区，以获取海啸影响的数据，包括淹没、上升、水流深度和侵蚀。海啸的许多证据都很脆弱，很快就被侵蚀或消失了。海啸的方向可以通过草的方向来确定，海啸的高度可以从建筑物或建筑物损坏的水痕中看出;树木或灌木丛中的碎片很常见。海啸过后，幸存者急于清理现场，冲走证据，让生活恢复正常。雨、风、海浪等自然过程也会削弱海啸的证据。由于许多证据是短暂的，不仅科学家渴望迅速进行观察，太多的快速反应和初步调查最终成为唯一的调查。调查的目的是更好地了解海啸及其与震源机制（此处指地震）的关系，并制定更好的减灾战略供今后使用。现在，海啸科学家第一次被邀请到受灾地区，他们面临的任务是巨大的。有适当技能的人数量有限，破坏的规模巨大-面积可能有数千平方公里。要获得这一地区的数据充其量是具有挑战性的，因此来自日本以外的国际科学家已被邀请到该国研究海啸;救援行动的进行已经有了很大的延迟，所以现在必须立即做出反应，该提案的PI教授大卫塔平是受邀的科学家之一。此外，需要新的方法来更好地科普事件的规模。为了满足这一需求，我们建议访问海啸淹没区，以收集海啸沉积物和海啸影响的数据。此外，我们将制定一个综合的方法，在获得实地数据之前，先对淹没区进行基于桌面的绘图，然后进行实地工作。因此，实地工作将是对先前解释的验证。具有重要意义的是，在海啸发生后，第一次出于人道主义原因发布了高分辨率卫星图像，以协助从事减灾工作的救援人员和科学家。对卫星图像的解读不仅将指导实地行动，而且图像和解读将上载到实地绘图计算机。然后，将通过数字方式获取关于海啸淹没、水流方向、侵蚀和沉积区位置以及海岸各方面的实地数据，对案头判读进行修正和改进，从而更好地了解海啸淹没是如何发生的。在下游，这些数据将上传到一个以数字地形模型为模型的地理信息系统，以便确定人们在未来事件中可以逃生的安全区域。绘制淹没区域的地图也将有助于更好地模拟海啸的发生。对海啸沉积物的调查将有助于更好地辨别过去的海啸事件，并改进风险战略。