收稿：2021-04-30，
纸质出版：2022-01-07
移动端阅览
离水辐亮度
L
w
（Water-leaving radiance）是水色遥感现场观测中的关键物理量之一，由其计算获得的遥感反射率
R
rs
（Remote sensing reflectance）是水色遥感参数反演的最基本参数。天空光遮挡法SBA（Skylight-blocked approach）可以直接测量水体离水辐亮度，作为一种新兴方法具有较强的推广应用潜力。本文介绍了基于天空光遮挡法的便携版漂浮式光学浮标FOBY-P（the Portable Floating Optical Buoy），其具有浮体自阴影小、布放简便等优势，在中国近海开展的现场观测实验结果表明：（1）FOBY-P结构设计上能在一定程度上避免太阳天顶角较大条件下浮体的自阴影遮挡影响，初步评估结果表明其400—700 nm自阴影影响在浑浊水体
<
5%，在清洁水体约为1%—3%；（2）在高海况下，传感器倾角随海况增大而变化剧烈，FOBY-P能保证在3—4级海况下观测倾角小于5°的有效观测占比超过50%；（3）通过与基于水面以上法的三通道TriOS RAMSES高光谱辐射计同步观测结果对比，二者一致性较高（
r
>
0.9），在490—565 nm波长范围内
R
rs
的偏差
<
5%，差异可能由观测方法不同引起，水面之上法水—气界面校正的不确定性可能是引起部分偏差的重要因素之一。该研究表明便携版漂浮式光学浮标（FOBY-P）可满足近海较高等级海况（3—4级）下的复杂水体现场观测需求，随着针对FOBY-P的数据质量控制与处理方法的不断优化，有望获取更高质量的现场水体光谱观测结果。
Water-leaving radiance (
L
w
) or remote sensing reflectance (
R
rs
) is a fundamental parameter of water color remote sensing. It has been a long-standing and challenging goal to precisely measure
L
w
. Skylight-Blocked Approach (SBA)
a novel approach for
in-situ
water spectrum measurement
can observe
L
w
directly screening the impact of the skylight in above-water method. It is not necessary to fulfill complicated post-processing to derive
L
w
by using SBA
which makes it has great potential to be used in different types of water body. However
there is not an automatic portable instrument to obtain water spectrum through SBA until now. In this study
a portable floating optical buoy (FOBY-P) is developed and tested. FOBY-P has its advantages with a smaller self-shading and an easier deployment compared with previous versions of FOBY with a circular floating body. The
in-situ
measurements in the coast of China through FOBY-P were carried out from October to November 2018 to test the buoy system. The results showed that 1) The self-shading effect of the floating body on the
L
w
observation under a large solar zenith angle can be effectively avoided by the tripod design of FOBY-P. The errors caused by the self-shading were less than 5% for the
R
rs
of 400—700 nm when it was used in turbid water. And the self-shading effect was only 1%—3% used in clear water; 2) FOBY-P can keep the sensor stable in the different sea state levels. Its effective observation ratio (the tilt angle less than 5°) is over 98% in the 1st sea state. The sensor tilt angle would be greater and greater when the sea state becomes worse. However
the ratio can still reach approximately 50% for the 3rd and 4th sea state; 3) The derived results of FOBY-P are in good agreement with those of TriOS RAMSES sensors. The correlation coefficient
r
between the
R
rs
of FOBY-P and that of TriOS RAMSES is larger than 0.9
and the
R
rs
difference of them is less than 5% for 490—565 nm. The difference may be caused by the different processing procedures of the two systems with different approaches. The water-air interface correction processing may be one of the factors to cause the uncertainty of TriOS RAMSES observations with above-water method. The result shows that FOBY-P has some advantages in platform stability
ease of use
and measurement accuracy as an automatic water spectrum acquisition instrument based on SBA. In general
FOBY-P can satisfy the requirements of in-situ measurement of
R
rs
in optically complex coastal waters
even during moderate sea state to provide high-quality data. Furthermore
it is only the first version of FOBY-P and further optimization in the design and data processing would improve the performance of the instrument.
Ahn Y H , Ryu J H and Moon J E . 1999 . Development of redtide and water turbidity algorithms using ocean color satellite . KORDI Report No. BSPE : 98721 - 00
Antoine D . 2012 . Ocean-Colour Observations from a Geostationary Orbit. Dartmouth, NS, Canada: International Ocean Colour Coordinating Group [ DOI: 10.25607/OBP-103 http://dx.doi.org/10.25607/OBP-103 ]
Chen X L , Lin G , Shi L H , Shan Y J and Shang S L . 2016 . Study on the shading issue of SBA in high-chlorophyll waters . Journal of Xiamen University (Natural Science) , 55 ( 2 ): 203 - 209
陈旭磊 , 林供 , 石良海 , 单宇杰 , 商少凌 . 2016 . 天空光遮蔽法在高叶绿素水体中的阴影问题研究 . 厦门大学学报(自然科学版) , 55 ( 2 ): 203- 209 [ DOI: 10.6043/j.issn.0438-0479.2016.02.010 http://dx.doi.org/10.6043/j.issn.0438-0479.2016.02.010 ]
Cui T W , Song Q J , Tang J W and Zhang J . 2013 . Spectral variability of sea surface skylight reflectance and its effect on ocean color . Optics Express , 21 ( 21 ): 24929 - 24941 [ DOI: 10.1364/OE.21.024929 http://dx.doi.org/10.1364/OE.21.024929 ]
Gordon H R , Brown O B and Jacobs M M . 1975 . Computed relationships between the inherent and apparent optical properties of a flat homogeneous ocean . Applied Optics , 14 ( 2 ): 417 - 427 [ DOI: 10.1364/AO.14.000417 http://dx.doi.org/10.1364/AO.14.000417 ]
Hooker S B , Lazin G , Zibordi G and McLean S . 2002 . An evaluation of above- and in-water methods for determining water-leaving radiances . Journal of Atmospheric and Oceanic Technology , 19 ( 4 ): 486 - 515 [ DOI: 10.1175/1520-0426(2002)019<0486:AEOAAI>2.0.CO; 2 http://dx.doi.org/10.1175/1520-0426(2002)019<0486:AEOAAI>2.0.CO;2 ]
Jiang D L , Matsushita B , Pahlevan N , Gurlin D , Lehmann M K , Fichot C G , Schalles J , Loisel H , Binding C , Zhang Y L , Alikas K , Kangro K , Uusõue M , Ondrusek M , Greb S , Moses W J , Lohrenz S and O’Donnell D . 2021 . Remotely estimating total suspended solids concentration in clear to extremely turbid waters using a novel semi-analytical method . Remote Sensing of Environment , 258 : 112386 [ DOI: 10.1016/j.rse.2021.112386 http://dx.doi.org/10.1016/j.rse.2021.112386 ]
Lee Z , Ahn Y H , Mobley C and Arnone R . 2010 . Removal of surface-reflected light for the measurement of remote-sensing reflectance from an above-surface platform . Optics Express , 18 ( 25 ): 26313 - 26324 [ DOI: 10.1364/OE.18.026313 http://dx.doi.org/10.1364/OE.18.026313 ]
Lee Z , Pahlevan N , Ahn Y H , Greb S and O’Donnell D . 2013 . Robust approach to directly measuring water-leaving radiance in the field . Applied Optics , 52 ( 8 ): 1693 - 1701 [ DOI: 10.1364/AO.52.001693 http://dx.doi.org/10.1364/AO.52.001693 ]
Lee Z , Wei J W , Shang Z H , Garcia R , Dierssen H , Ishizaka J and Castagna A . 2019 . On-water radiometry measurements: skylight-blocked approach and data processing (Appendix to IOCCG Protocol Series (2019)//Zibordi G, Voss K J, Johnson B C and Mueller J L, eds. Protocols for Satellite Ocean Colour Data Validation: In Situ Optical Radiometry . IOCCG Ocean Optics and Biogeochemistry Protocols for Satellite Ocean Colour Sensor Validation, Volume 3 .0. Dartmouth, NS, Canada : IOCCG
Lee Z , Wei J W , Voss K , Lewis M , Bricaud A and Huot Y . 2015 . Hyperspectral absorption coefficient of pureseawater in the range of 350-550nm inverted from remote sensing reflectance . Applied Optics , 54 ( 3 ): 546 - 558 [ DOI: 10.1364/AO.54.000546 http://dx.doi.org/10.1364/AO.54.000546 ]
Li T J . 2012 . China’s Coastal Oceans: Marine Optical Properties and Remote Sensing . Beijing : China Ocean Press
李铜基 . 2012 . 中国近海海洋: 海洋光学特性与遥感 . 北京 : 海洋出版社
Lin H , Lee Z , Lin G and Yu X L . 2020 . Experimental evaluation of the self-shadow and its correction for on-water measurements of water-leaving radiance . Applied Optics , 59 ( 17 ): 5325 - 5334 [ DOI: 10.1364/AO.391633 http://dx.doi.org/10.1364/AO.391633 ]
Morel A . 1980 . In-water and remote measurements of ocean color . Boundary-Layer Meteorology , 18 ( 2 ): 177 - 201 [ DOI: 10.1007/BF00121323 http://dx.doi.org/10.1007/BF00121323 ]
Mueller J , MuelIer J L , Pietras C , Hooker S B , Clark D K , Morel A , Frouin R and Fargion G S . 2002 . Ocean optics protocols for satellite ocean color sensor validation, revision 3, volumes 1 and 2 . NASA tech. memo 210004
Pahlevan N , Schott J R , Franz B A , Zibordi G , Markham B , Bailey S , Schaaf C B , Ondrusek M , Greb S and Strait C M . 2017 . Landsat 8 remote sensing reflectance ( R rs ) products: evaluations, intercomparisons, and enhancements . Remote Sensing of Environment , 190 : 289 - 301 [ DOI: 10.1016/j.rse.2016.12.030 http://dx.doi.org/10.1016/j.rse.2016.12.030 ]
Pahlevan N , Sheldon P , Peri F , Wei J W , Shang Z H , Sun Q S , Chen R F , Lee Z , Schaaf C B , Schott J R and Loveland T . 2016 . Calibration/validation of Landsat-derived ocean colour products in Boston Harbour. The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, XLI-B 8 : 1165 - 1168 [ DOI: 10.5194/isprs-archives-XLI-B8-1165-2016 http://dx.doi.org/10.5194/isprs-archives-XLI-B8-1165-2016 ]
Pahlevan N , Smith B , Schalles J , Binding C , Cao Z G , Ma R H , Alikas K , Kangro K , Gurlin D , Hà N , Matsushita B , Moses W , Greb S , Lehmann M K , Ondrusek M , Oppelt N and Stumpf R . 2020 . Seamless retrievals of chlorophyll-a from Sentinel-2 (MSI) and Sentinel-3 (OLCI) in inland and coastal waters: a machine-learning approach . Remote Sensing of Environment , 240 : 111604 [ DOI: 10.1016/j.rse.2019.111604 http://dx.doi.org/10.1016/j.rse.2019.111604 ]
Ruddick K G , Voss K , Banks A C , Boss E , Castagna A , Frouin R , Hieronymi M , Jamet C , Johnson B C , Kuusk J , Lee Z , Ondrusek M , Vabson V and Vendt R . 2019 . A review of protocols for fiducial reference measurements of downwelling irradiance for the validation of satellite remote sensing data over water . Remote Sensing , 11 ( 15 ): 1742 [ DOI: 10.3390/rs11151742 http://dx.doi.org/10.3390/rs11151742 ]
Ruddick K G , Voss K , Boss E , Castagna A , Frouin R , Gilerson A , Hieronymi M , Johnson B C , Kuusk J , Lee Z , Ondrusek M , Vabson V and Vendt R . 2019 . A review of protocols for fiducial reference measurements of water-leaving radiance for validation of satellite remote-sensing data over water . Remote Sensing , 11 ( 19 ): 2198 [ DOI: 10.3390/rs11192198 http://dx.doi.org/10.3390/rs11192198 ]
Shang Z H , Lee Z , Dong Q and Wei J W . 2017 . Self-shading associated with a skylight-blocked approach system for the measurement of water-leaving radiance and its correction . Applied Optics , 56 ( 25 ): 7033 - 7040 [ DOI: 10.1364/AO.56.007033 http://dx.doi.org/10.1364/AO.56.007033 ]
Tanaka A , Sasaki H and Ishizaka J . 2006 . Alternative measuring method for water-leaving radiance using a radiance sensor with a domed cover . Optics Express , 14 ( 8 ): 3099 - 3105 [ DOI: 10.1364/OE.14.003099 http://dx.doi.org/10.1364/OE.14.003099 ]
Tang J W . 1999 . The Simulation of Marine Optical Properties and Color Sensing Models . Beijing : Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences
唐军武 . 1999 . 海洋光学特性模拟与遥感模型 . 北京 : 中国科学院遥感应用研究所
Tian L Q , Li S , Li Y , Sun Z H , Song Q J and Zhao J . 2020 . A Floating Optical Buoy (FOBY) for direct measurement of water-leaving radiance based on the skylight-blocked approach (SBA): an experiment in Honghu Lake, China . Journal of Geophysical Research: Oceans , 125 ( 10 ):
e2020JC 016322 [ DOI: 10.1029/2020JC016322 http://dx.doi.org/10.1029/2020JC016322 ]
Tian L Q , Li S , Sun X H , Tong R Q , Song Q J , Sun Z H and Li Y . 2020 . Development of a novel floating water spectral measurement system based on skylight-blocked approach . Spectroscopy and Spectral Analysis , 40 ( 9 ): 2756 - 2763
田礼乔 , 李森 , 孙相晗 , 童如清 , 宋庆君 , 孙兆华 , 李勇 . 2020 . 基于天空光遮挡法的漂浮式水体光谱测量系统研制 . 光谱学与光谱分析 , 40 ( 9 ): 2756 - 2763 ) [DOI: 10.3964/j.issn.1000-0593 (202009- 2756 - 08 ]
Wang J W , Lee Z , Wei J W and Du K P . 2020 . Atmospheric correction in coastal region using same-day observations of different sun-sensor geometries with a revised POLYMER model . Optics Express , 28 ( 18 ): 26953 - 26976 [ DOI: 10.1364/OE.393968 http://dx.doi.org/10.1364/OE.393968 ]
Wei J W , Lee Z , Garcia R , Zoffoli L , Armstrong R A , Shang Z H , Sheldon P and Chen R F . 2018 . An assessment of Landsat-8 atmospheric correction schemes and remote sensing reflectance products in coral reefs and coastal turbid waters . Remote Sensing of Environment , 215 : 18 - 32 [ DOI: 10.1016/j.rse.2018.05.033 http://dx.doi.org/10.1016/j.rse.2018.05.033 ]
Wei J W , Lee Z , Lewis M , Pahlevan N , Ondrusek M and Armstrong R . 2015 . Radiance transmittance measured at the ocean surface . Optics Express , 23 ( 9 ): 11826 - 11837 [ DOI: 10.1364/OE.23.011826 http://dx.doi.org/10.1364/OE.23.011826 ]
Wei J W , Lee Z , Shang S L and Yu X L . 2019 . Semianalytical derivation of phytoplankton, CDOM, and detritus absorption coefficients from the Landsat 8/OLI reflectance in coastal waters . Journal of Geophysical Research: Oceans , 124 ( 6 ): 3682 - 3699 [ DOI: 10.1029/2019JC015125 http://dx.doi.org/10.1029/2019JC015125 ]
Wei J W , Wang M H , Lee Z , Ondrusek M , Zhang S and Ladner S . 2021 . Experimental analysis of the measurement precision of spectral water-leaving radiance in different water types . Optics Express , 29 ( 2 ): 2780 - 2797 [ DOI: 10.1364/OE.413784 http://dx.doi.org/10.1364/OE.413784 ]
Yu X L , Lee Z , Shang Z H , Lin H and Lin G . 2021 . A simple and robust shade correction scheme for remote sensing reflectance obtained by the skylight-blocked approach . Optics Express , 29 ( 1 ): 470 - 486 [ DOI: 10.1364/OE.412887 http://dx.doi.org/10.1364/OE.412887 ]
Zhang Q Y . 1985 . Introduction to Meteorological Operation . Beijing : China Meteorological Press
张庆阳 . 1985 . 气象业务入门 . 北京 : 气象出版社
Zibordi G , Holben B , Hooker S B , Mélin F , Berthon J F , Slutsker I , Giles D , Vandemark D , Feng H , Rutledge K , Schuster G and Al Mandoos A . 2006 . A network for standardized ocean color validation measurements . Eos, Transactions American Geophysical Union , 87 ( 30 ): 293 - 297 [ DOI: 10.1029/2006EO300001 http://dx.doi.org/10.1029/2006EO300001 ]
Zibordi G , Mélin F , Berthon J F , Holben B , Slutsker I , Giles D , D’Alimonte D , Vandemark D , Feng H , Schuster G , Fabbri B E , Kaitala S and Seppälä J . 2009 . AERONET-OC: a network for the validation of ocean color primary products . Journal of Atmospheric and Oceanic Technology , 26 ( 8 ): 1634 - 1651 [ DOI: 10.1175/2009JTECHO654.1 http://dx.doi.org/10.1175/2009JTECHO654.1 ]
Zoffoli M L , Lee Z , Ondrusek M , Lin J F , Kovach C , Wei J W and Lewis M . 2017 . Estimation of transmittance of solar radiation in the visible domain based on remote sensing: evaluation of models using in situ data . Journal of Geophysical Research: Oceans , 122 ( 11 ): 9176 - 9188 [ DOI: 10.1002/2017JC013209 http://dx.doi.org/10.1002/2017JC013209 ]
相关作者
相关机构
京公网安备11010802024621
