Petascale Polar Topography Production

极地地区的变化比地球上任何其他地区都要快，海岸侵蚀、永久冻土流失、冰川变薄和其他变化的速度都在加快。然而，两极也是观测最少的地区之一，这是因为在以前的全球遥感调查中，两极相对难以进入，而且覆盖范围有限。 该项目将利用Blue沃茨的高性能计算能力，为地球两极生成高分辨率、高质量、随时间变化的开放式数字高程模型（DEM）。这套数据集是衡量和了解极地景观快速、持续变化所必需的，也是极地社区进行影响缓解和适应规划所必需的。制作的数字高程模型将免费分发给科学界和广大公众。 该项目将使用蓝色沃茨制作2米分辨率的数字高程模型，在南极和北极地区的绝对精度约为1米或更高，相对精度为0.2米。 该项目包括重复、高分辨率和高精度地形测绘的能力，其形式是由五个极轨道太阳同步地球成像仪（WorldView 1-4和GeoEye-1）组成的DigitalGlobe星座提供的亚米级立体图像，以及IKONOS和QuickBird的档案。 利用这些卫星图像，可以在各种地形类型和光照条件下（包括“平坦的白色”冰盖内部和阴影中的山体）利用重叠图像对进行精确的立体摄影测量DEM构建。DEM随时间变化的收集对于研究极地变化的科学家来说是非常宝贵的。 该项目已获得获取和维护图像的资源、对结果进行后处理的工具、软件开发时间以及分发数字高程模型的方法。 所有DEM将通过极地地理空间中心（PGC）网站和包括国家地理空间局（NGA）和NASA在内的联盟以及亚马逊网络服务和地理空间软件公司ESRI进行分发。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

The polar regions are changing faster than any other region of the Earth, with accelerating rates of coastal erosion, permafrost loss, glacier thinning, and other changes. Yet the poles are also among the least well observed regions, due to both their relative inaccessibility and coverage limitations in prior global surveys by remote sensing. The project will use the high performance computing capabilities of Blue Waters to produce high-resolution, high-quality, time-dependent, and openly distributed digital elevation models (DEMs) for the Earth's poles. This data set is needed for measuring and understanding rapid, ongoing changes to the polar landscapes, as well as for impact mitigation and adaptation planning by polar communities. The produced DEMs will be distributed at no cost to the science community and public at large. The project will use Blue Waters to produce 2m resolution DEMs with absolute accuracies of approximately 1m or better and relative accuracies of 0.2m over the Antarctic and Arctic regions. The project incorporates the capability for repeat, high-resolution and high-precision topographic mapping in the form of sub-meter stereoscopic imagery from the DigitalGlobe constellation of five polar-orbiting sun-synchronous Earth imagers (WorldView 1-4 and GeoEye-1), as well as the archive of IKONOS and QuickBird. These satellites images allow for precise stereo photogrammetric DEM construction from overlapping image pairs over a wide range of terrain types and light conditions, including the "flat white" interior of ice sheets and shadowed mountain faces. The time-dependent collection of DEMs will be invaluable to scientists studying change in the polar region. Resources for obtaining and maintaining the imagery, tools for post-processing the results, software development time, and methods for distributing the DEMs have been secured by the project. All DEMs will be publically distributed through the Polar Geospatial Center (PGC) website and a consortium including the National Geospatial Agency (NGA) and NASA, as well as Amazon web services and the geospatial software company ESRI.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.