Satellite retrieval of the absorption coefficient of phytoplankton phycoerythrin pigment: theory and feasibility status.
Satellite retrieval of the absorption coefficient of phytoplankton phycoerythrin pigment: theory and feasibility status.
复制标题
DOI：
10.1364/ao.38.007431
复制
发表时间：
1999-12
期刊：
影响因子：
1.9
通讯作者：
F. Hoge;C. W. Wright;P. Lyon;R. Swift;J. Yungel
中科院分区：
文献类型：
--
作者：
F. Hoge;C. W. Wright;P. Lyon;R. Swift;J. Yungel
利用海洋辐射模型反演方法建立了一种综合的算法，用于提取富含PUB的第一类藻红胆素(PEB)和缺乏PUB的第二类PEB的吸收系数(以及常见的三大固有光学性质：总后向散射系数和发色溶解有机物(CDOM)-碎屑和浮游植物的吸收系数)。然后对这种完全建模的反演算法进行简化，以产生一种混合的建模-未建模的反演算法，其中藻红蛋白(PE)的吸收系数被反演为未建模的488 nm吸收(这超过了建模的浮游植物和CDOM碎屑的吸收系数)。每种算法都适用于离开水的辐射，但只有混合建模-未建模的反演才能产生可行的PE吸收系数的反演。通过与机载激光诱导的PEB荧光的相对比较，验证了PE吸收系数反演的有效性。通过直接矩阵求逆对四种固有光学性质进行模型化-非模型化恢复是快速且条件良好的，但精确度受到跨越所有四个光谱段的三个主要固有光学性质模型的精度的强烈限制。确定了几个研究领域来加强基于辐射模型的反演：(A)改进的PEB和PUB吸收系数模型，(B)PUB生色团结合部位的生色团替代引起的PE光谱位移，(C)特定吸收敏感的浮游植物吸收模型，(D)总成分背向散射模型，(E)未建模的类胡萝卜素和藻蓝蛋白吸收，这些吸收现在不在以叶绿素为主的浮游植物吸收系数模型中考虑，以及(F)迭代反演技术，以求解只有5个辐射的6个组分。虽然在PE吸收的卫星恢复方面已经取得了相当大的进展，但目前对于常规的全球应用来说，反演的成熟度还不够。相反，它目前必须在区域基础上使用，在那里可以提供本地化的船舶和飞机验证。该算法是为中分辨率成像光谱仪(MODIS)传感器开发的，但也适用于任何具有类似波段位置的传感器。
Oceanic radiance model inversion methods are used to develop a comprehensive algorithm for retrieval of the absorption coefficients of phycourobilin (PUB) pigment, type I phycoerythrobilin (PEB) pigment rich in PUB, and type II PEB deficient in PUB pigment (together with the usual "big three" inherent optical properties: the total backscattering coefficient and the absorption coefficients of chromophoric dissolved organic matter (CDOM)-detritus and phytoplankton). This fully modeled inversion algorithm is then simplified to yield a hybrid modeled-unmodeled inversion algorithm in which the phycoerythrin (PE) absorption coefficient is retrieved as unmodeled 488-nm absorption (which exceeds the modeled phytoplankton and the CDOM-detritus absorption coefficients). Each algorithm was applied to water-leaving radiances, but only hybrid modeled-unmodeled inversions yielded viable retrievals of the PE absorption coefficient. Validation of the PE absorption coefficient retrieval was achieved by relative comparison with airborne laser-induced PEB fluorescence. The modeled-unmodeled retrieval of four inherent optical properties by direct matrix inversion is rapid and well conditioned, but the accuracy is strongly limited by the accuracy of the three principal inherent optical property models across all four spectral bands. Several research areas are identified to enhance the radiance-model-based retrievals: (a) improved PEB and PUB absorption coefficient models, (b) PE spectral shifts induced by PUB chromophore substitution at chromophore binding sites, (c) specific absorption-sensitive phytoplankton absorption modeling, (d) total constituent backscattering modeling, (e) unmodeled carotinoid and phycocyanin absorption that are not now accounted for in the chlorophyll-dominated phytoplankton absorption coefficient model, and (f) iterative inversion techniques to solve for six constituents with only five radiances. Although considerable progress has been made toward the satellite recovery of PE absorption, the maturity of the retrieval is presently insufficient for routine global application. Instead it must currently be used on a regional basis where localized ship and aircraft validation can be made available. The algorithm was developed for the MODIS (Moderate-Resolution Imaging Spectroradiometer) sensor but is applicable to any sensor having comparable band locations.