Correction for the non-nadir viewing geometry of AERONET-OC above water radiometry data: an estimate of uncertainties.
Correction for the non-nadir viewing geometry of AERONET-OC above water radiometry data: an estimate of uncertainties.
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对 AERONET-OC 水上辐射测量数据的非最低点观察几何的校正：不确定性的估计。
DOI：
10.1364/oe.26.00a541
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发表时间：
2018
期刊：
影响因子：
3.8
通讯作者：
Z. Lee
中科院分区：
文献类型：
--
作者：
M. Talone;G. Zibordi;Z. Lee
通过现场测量和两种不同的校正方法，研究了非最低点观测几何形状对水面辐射测量数据的影响：一种是针对一类水域开发的以叶绿素a浓度(CHLA)为中心的校正方法，另一种是针对任何水体类型提出的基于海水固有光学特性(IOP)的校正方法。该研究特别参考了气溶胶机器人网络海洋颜色部分的数据，重点评估了影响对空中视角为40°、视向与太阳之间的相对方位角为90°的数据进行非最低点修正的不确定因素。这项研究分析了来自欧洲不同海域的AERONET-OC离水辐射数据，以确定使用CHLA和IOP方法进行的校正之间的差异。此外，利用在具有不同光学复杂性的水域中收集的数据，包括在最低点和28.6°水中视角(对应于空中40°)和90°相对方位角下测量的离水辐射，研究了两种校正方法的不确定度。对以各种光学复杂水域为特征的AERONET-OC站点数据的分析结果表明，对于基于IOP的方法，从412 nm到667 nm的不确定度在20%到35%之间。相反，基于CHLA的不确定度在很大程度上随波长和水类型的不同而不同，在412 nm处的不确定度约为55%，在490 nm和551 nm之间的不确定度为20%-40%，在667 nm处的不确定度超过60%。
The effects of non-nadir viewing geometry in above-water radiometry data were investigated using field measurements and two different correction approaches: one centered on chlorophyll-a concentration (Chla) developed for Case-1 waters, and the other relying on seawater inherent optical properties (IOP) proposed for any water type. With specific reference to data from the Ocean Color component of the AErosol RObotic NETwork (AERONET-OC), the study focused on the assessment of the uncertainties affecting corrections for non-nadir view of data collected with 40° in-air viewing angle and with 90° relative azimuth between viewing direction and sun. The study analyzed AERONET-OC water-leaving radiance data from different European seas to determine differences between corrections performed with the Chla- and the IOP-based approaches. Additionally, data collected in waters characterized by different optical complexity and comprising water-leaving radiances measured at nadir and with 28.6° in-water viewing angle (corresponding to 40° in-air) and 90° relative azimuth, were used to investigate the uncertainties of the two correction approaches. Results from the analysis of data from AERONET-OC sites characterized by a variety of optically complex waters, indicate corrections with uncertainties between 20% and 35% from 412 nm to 667 nm for the IOP-based approach. Conversely, uncertainties for the Chla-based one largely vary with wavelength and water type, with values of approximately 55% at 412 nm, 20-40% between 490 nm and 551 nm, and exceeding 60% at 667 nm.