Toward global mapping of river discharge using satellite images and at-many-stations hydraulic geometry
Toward global mapping of river discharge using satellite images and at-many-stations hydraulic geometry
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DOI：
10.1073/pnas.1317606111
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发表时间：
2014-04-01
影响因子：
11.1
通讯作者：
Smith, Laurence C.
中科院分区：
文献类型：
--
作者：
Gleason, Colin J.;Smith, Laurence C.
河流为许多人类社会和生态系统提供了至关重要的水源，但全球对其流量的了解却很匮乏。我们表明，对河流绝对流量（以立方米每秒为单位）的有用估算可能仅从卫星图像得出，完全不需要地面信息或先验信息。这种方法之所以可行，是因为发现了一种对天然河流具有独特根本性的特征尺度定律，在此将其称为河流的多站水力几何形态。利用美国、加拿大和中国三条河流上的陆地卫星专题制图仪图像进行的首次演示得出的绝对流量与传统的现场测量站测量值相差在20% - 30%以内，并且能很好地追踪流量随时间的变化。在这样的精度范围内，利用重复成像对全球河流资源进行量化似乎成为可能，无论是追溯过去还是展望未来，这对水资源管理、粮食安全、生态系统研究、洪水预报和地缘政治都具有重大影响。
Rivers provide critical water supply for many human societies and ecosystems, yet global knowledge of their flow rates is poor. We show that useful estimates of absolute river discharge (in cubic meters per second) may be derived solely from satellite images, with no ground-based or a priori information whatsoever. The approach works owing to discovery of a characteristic scaling law uniquely fundamental to natural rivers, here termed a river's at-many-stations hydraulic geometry. A first demonstration using Landsat Thematic Mapper images over three rivers in the United States, Canada, and China yields absolute discharges agreeing to within 20-30% of traditional in situ gauging station measurements and good tracking of flow changes over time. Within such accuracies, the door appears open for quantifying river resources globally with repeat imaging, both retroactively and henceforth into the future, with strong implications for water resource management, food security, ecosystem studies, flood forecasting, and geopolitics.