摘要
为了评估和分析激光雷达探测全球海洋光学参数的性能,根据激光雷达方程和给定的激光雷达参数,使用MODIS Level 3全球年平均的海水吸收系数a(λ)和后向散射系数bb(λ)数据作为海水光学参数的参考值,对蓝绿光星载海洋激光雷达在全球海洋的探测深度进行了估算和分析。研究结果表明:星载海洋激光雷达探测深度的分布主要依赖于探测波长和水体光学性质,清洁大洋水的最优探测波长在460 nm左右,白天和夜间的最大探测深度分别为~110 m和~120 m;沿岸浑浊水的最优探测波长多在500 nm以上,最大探测深度只能达到20 m或更浅。探测波长为470~480 nm时,星载海洋激光雷达在全球范围内的平均探测能力最佳。
In order to evaluate and analyze the detection performance of lidar for optical properties in global ocean, the detection depth of spaceborne oceanographic lidar operating in blue-green spectral region was estimated and analyzed. This research was based on lidar equation and given lidar parameters.MODIS Level 3 annual averaged global water absorption coefficient a(λ) and backscatter coefficient bb(λ)were used as reference values for optical properties of sea water. The results show the distribution of detection depth depends on both detection wavelength and water optical properties. In clear open ocean,the best detection wavelength is near 460 nm and the maximum detection depths are approximated 110 m and 120 m in daytime and nighttime, respectively. In turbid coastal water, the best detection wavelength is mostly longer than 500 nm and the maximum detection depths can only reach 20 m or even shallower.The spaceborne oceanographic lidar achieves best global detection performance when the detection wavelength is between 470 nm and 480 nm.
引文
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