Japan Tsunami Urgency Response

2011年3月11日14时46分（日本当地时间），日本本州岛东海岸发生里氏9.0级地震，并引发海啸，淹没了附近400公里长的海岸线。海啸高达17米，它超越了许多为保护沿海地区而建造的防护墙，至少有27,000人死亡，超过35万人无家可归。这次地震的规模与2004年印度洋地震类似。在这个地震多发/构造活跃的地区，小型海啸并不罕见，但这种规模的海啸却很罕见，上一次如此大规模的海啸发生在1896年，当时有2.7万人丧生。在救援行动之后，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。关于海啸的许多证据都很脆弱，很快就会被侵蚀或消失。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上的水迹或建筑物的损坏程度来判断；被树木或灌木丛夹住的碎片很常见。海啸过后，幸存者急于清理，洗去证据，让他们的生活恢复正常。自然过程——雨、风、浪——也削弱了海啸的证据。由于许多证据都是短暂的，不仅科学家们渴望快速观察，而且太多的快速反应和初步调查最终都是唯一进行的调查。调查的目的是更好地了解海啸及其与震源机制（在本例中是地震）的关系，并制定改进的减灾战略以供今后使用。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，而且破坏的规模巨大——可能有数千平方公里的面积。获取这一地区的数据是极具挑战性的，因此日本以外的国际科学家被邀请到该国研究海啸；救援行动的进行有很大的延迟，所以现在必须立即作出反应，该提案的首席执行官大卫·塔平教授是受邀的科学家之一。此外，需要新的方法来更好地应对事件的规模。为了满足需求，我们建议访问海啸淹没地区，收集海啸沉积物和海啸影响的数据。此外，我们将开发一种综合方法，在获取现场数据之前对被淹没地区进行基于桌面的测绘，然后进行实地工作。因此，实地工作将证实先前的解释。值得注意的是，海啸发生后，出于人道主义原因首次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。卫星图像的判读不仅将指导实地作业，而且图像和判读也将上传到实地测绘计算机上。然后，通过对海啸淹没、水流方向、侵蚀和沉积区域位置以及海岸各个方面的实地数据的数字采集，将对基于桌面的解释进行修正和改进，这些数据将使人们更好地了解海啸淹没是如何发生的。随后，这些数据将被上传到一个以数字地形模型为模型的GIS上，以确定人们在未来事件中可以逃到的安全区域。绘制被淹没地区的地图也将有助于建立更好的海啸模型。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策略。

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.