气候变化领域集成服务门户(CCPortal): River-ice and water velocities using the Planet optical cubesat constellation

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DOI	10.5194/hess-23-4233-2019
	River-ice and water velocities using the Planet optical cubesat constellation
	Kääb A.; Altena B.; Mascaro J.
发表日期	2019
ISSN	1027-5606
起始页码	4233
结束页码	4247
卷号	23 期号:10
英文摘要	The PlanetScope constellation consists of ĝ1/4150 optical cubesats that are evenly distributed like strings of pearls on two orbital planes, scanning the Earth's land surface once per day with an approximate spatial image resolution of 3 m. Subsequent cubesats on each of the orbital planes image the Earth surface with a nominal time lag of approximately 90 s between them, which produces near-simultaneous image pairs over the across-track overlaps of the cubesat swaths. We exploit this short time lag between subsequent Planet cubesat images to track river ice floes on northern rivers as indicators of water surface velocities. The method is demonstrated for a 60 km long reach of the Amur River in Siberia, and a 200 km long reach of the Yukon River in Alaska. The accuracy of the estimated horizontal surface velocities is of the order of ±0.01 m s-1. The application of our approach is complicated by cloud cover and low sun angles at high latitudes during the periods where rivers typically carry ice floes, and by the fact that the near-simultaneous swath overlaps, by design, do not cover the complete Earth surface. Still, the approach enables direct remote sensing of river surface velocities for numerous cold-region rivers at a number of locations and occasionally several times per year - which is much more frequent and over much larger areas than currently feasible. We find that freeze-up conditions seem to offer ice floes that are generally more suitable for tracking, and over longer time periods, compared with typical ice break-up conditions. The coverage of river velocities obtained could be particularly useful in combination with satellite measurements of river area, and river surface height and slope. © 2019. This work is distributed under the Creative Commons Attribution 4.0 License.
语种	英语
scopus关键词	Image resolution; Orbits; Remote sensing; Sea ice; Small satellites; Velocity; High Latitudes; Horizontal surfaces; Orbital planes; River velocity; Satellite measurements; Surface height; Surface velocity; Water velocities; Rivers; cloud cover; flow velocity; ice flow; image resolution; remote sensing; satellite imagery; spatial analysis; Alaska; Amur River; Siberia; United States; Yukon River
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159806
作者单位	Kääb, A., Department of Geosciences, University of Oslo, Oslo, 0316, Norway; Altena, B., Department of Geosciences, University of Oslo, Oslo, 0316, Norway; Mascaro, J., Planet, San Francisco, 94103, United States
推荐引用方式 GB/T 7714	Kääb A.,Altena B.,Mascaro J.. River-ice and water velocities using the Planet optical cubesat constellation[J],2019,23(10).
APA	Kääb A.,Altena B.,&Mascaro J..(2019).River-ice and water velocities using the Planet optical cubesat constellation.Hydrology and Earth System Sciences,23(10).
MLA	Kääb A.,et al."River-ice and water velocities using the Planet optical cubesat constellation".Hydrology and Earth System Sciences 23.10(2019).