相关实验视频
Updated: Jan 17, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
10.9K
概括
这项研究展示了一种使用海洋雷利散射校准卫星偏振传感器的新方法. 该技术可以获得准确的结果,特别是在最佳的观测条件下,使卫星极度测量更可靠.
科学领域:
- 遥感 遥感 遥感 遥感
- 大气光学是大气光学.
- 极极度度测试 (Polarimetry) 是一种极极度测试方法.
背景情况:
- 越来越多的太空偏振传感器需要强大的飞行校准方法.
- 代理校准方法是 radiometric 校准的成熟,但很少有人使用自然场景进行极度校准.
- 雷利散射在海洋上是可见光谱中大气反射信号的主要贡献者,可以准确地模拟.
研究的目的:
- 评估利用雷利散射在海洋上的潜力,用于卫星在飞行中的极化校准.
- 为了评估模拟大气顶部 (TOA) 线性极化度 (DOLP) 的准确性,考虑各种参数不确定性.
- 应用模拟的DOLP在飞行中校准定向极度度相机 (DPC) 并验证该方法.
主要方法:
- 使用辐射转移模拟来评估模拟DOLP (Pcal) 的可实现精度和误差因数 (δPcalfactor),因为气溶光学深度 (AOD),气溶模型 (AM),水蒸气柱 (CWV),臭氧柱 (O3),风速 (WS) 和叶绿素 (Chl) 的不确定性.
- 分析了偏振校准误差对波长和太阳观测几何学的依赖性.
- 模拟的DOLP被用于校准GaoFen-5上的DPC,并比较了六个海洋区域的校准结果.
主要成果:
- 在AOD和AM的不确定性被确定为雷利散射极化校准的主要错误来源,其次是WS. 和吸收气体的影响微不足道.
- 总DOLP误差 (δPcalTotal) 主要由散射角度 (SCA) 占据,并且随波长,太阳顶角 (SZA) 和视角顶角 (VZA) 增加而增加.
- 在优化的几何条件下 (SZA ≤40°,VZA ≤50°,阳光闪光角度 ≥60°,108° ≤SCA ≤145°),平均dPcalTotal在490nm时为0.0088,在670nm时为0.0217. DPC校准产生了0.0078在490nm和0.0213在670nm的标准误差.
结论:
- 在有利的几何条件下,利用雷利散射在海洋上进行卫星飞行中的极化校准是可行的和实用的.
- 优化的太阳观测几何选显著提高了极度测量校准结果的稳定性.
- 这项研究提出了一种可行的方法,用于校准卫星短可见波段的极度测量.
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