测绘学报 ›› 2026, Vol. 55 ›› Issue (7): 1240-1253.doi: 10.11947/j.AGCS.2026.20250484

• 大地测量学与导航 • 上一篇    

基于SWOT卫星的中国地区河流观测能力分析与精度评估

路浩1(), 冯伟1(), 王晓兵2, 陈威3, 钟敏1   

  1. 1.中山大学遥感科学与技术学院,广东 珠海 519082
    2.青岛市勘察测绘研究院,山东 青岛 266033
    3.湖北文理学院资源环境与旅游学院,湖北 襄阳 441053
  • 收稿日期:2025-11-19 修回日期:2026-07-07 发布日期:2026-08-18
  • 通讯作者: 冯伟 E-mail:luhao23@mail2.sysu.edu.cn;fengwei@mail.sysu.edu.cn
  • 作者简介:路浩(2000—),男,硕士,研究方向为水文大地测量学。 E-mail:luhao23@mail2.sysu.edu.cn
  • 基金资助:
    国家自然科学基金(42574068; 42504054)

Assessing the capability and accuracy of SWOT satellite river observations in China

Hao Lu1(), Wei Feng1(), Xiaobing Wang2, Wei Chen3, Min Zhong1   

  1. 1.School of Geospatial Engineering and Science, Sun Yat-sen University, Zhuhai 519082, China
    2.Qingdao Research Institute of Surveying and Mapping, Qingdao 266033, China
    3.College of Resource Environment and Tourism, Hubei University of Arts and Science, Xiangyang 441053, China
  • Received:2025-11-19 Revised:2026-07-07 Published:2026-08-18
  • Contact: Wei Feng E-mail:luhao23@mail2.sysu.edu.cn;fengwei@mail.sysu.edu.cn
  • About author:Lu Hao (2000—), male, master, majors in hydrogeodesy. E-mail: luhao23@mail2.sysu.edu.cn
  • Supported by:
    The National Natural Science Foundation of China(42574068; 42504054)

摘要:

本文评估了地表水与海洋地形(SWOT)宽刈幅测高卫星对中国地区河流的观测能力及其在河流水位和水位变化监测中的精度。在21天重访周期内,SWOT可对97.39%的中国河流河段进行至少一次的观测。基于301个水文站点的水位实测数据验证表明,SWOT监测中国河流水位变化的平均绝对误差(MAE)为0.35 m,水位变化的相关系数均值大于0.9。不同流域的验证结果显示,SWOT在海河、淮河、松辽流域和黄河流域的水位变化监测精度较高(MAE<0.3 m),而在珠江和长江流域误差相对较大。针对大坝附近因水位空间不连续导致的相位解缠错误,本文采用基于低相干水体识别与最优整周模糊度确定的校正方法,通过空间分割上下游水体并遍历不同整周模糊度以恢复正确高程。针对窄河流噪声非对称分布的特点,本文提出了基于空间连续性检验的多级自适应滤波算法(MAF),通过k近邻空间连续性检验识别异常点,并结合偏度特征自适应剔除离群值。在10个测试站点的验证中,经相位解缠校正与MAF算法处理后,水位监测的平均MAE从1.73 m降低至0.32 m。本文研究验证了SWOT卫星在中国地区河流水位变化监测的可靠性,可为大范围高精度水文参数获取提供了一种技术手段,对水资源管理和洪涝灾害监测具有重要应用价值。

关键词: SWOT卫星, 卫星测高, 河流水位, 相位解缠, 去噪

Abstract:

This study evaluates the observation capability and accuracy of the SWOT wide-swath altimetry satellite for monitoring river water levels and water level changes in China. Within a 21-day revisit cycle, SWOT can observe 97.39% of river reaches in China at least once. Validation against in situ water level data from 301 hydrological gauge stations demonstrates that SWOT achieves a mean absolute error (MAE) of 0.35 m for monitoring river water level variations in China, with an overall correlation coefficient greater than 0.9. Results across different basins indicate that SWOT exhibits higher monitoring accuracy in the Songhua-Liaohe, Haihe, Huaihe, and Yellow River basins (MAE<0.3 m), while relatively larger errors are observed in the Pearl River and Yangtze River basins. To address phase unwrapping errors near dams caused by spatial discontinuity of water levels, this study employs a correction method based on low-coherence water body identification and optimal integer ambiguity determination, which spatially separates upstream and downstream water bodies and iterates through different integer ambiguities to recover correct elevations. To address the asymmetric noise distribution characteristic of narrow rivers, this study proposes a multi-level adaptive filtering (MAF) algorithm based on spatial continuity testing, which identifies anomalous points through k-nearest neighbor spatial continuity testing and adaptively removes outliers based on skewness characteristics. Validation at 10 test stations shows that after phase unwrapping correction and MAF algorithm processing, the average MAE decreased from 1.73 m to 0.32 m. This research validates the reliability of SWOT satellite for river water level monitoring variations in China, providing a technical approach for large-scale, high-precision hydrological parameter acquisition, with important reference value for water resource management and flood disaster monitoring.

Key words: SWOT satellite, satellite altimetry, river water level, phase unwrapping, denoising

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