气候变化领域集成服务门户(CCPortal): Spectral range within global aCDOM(440) algorithms for oceanic, coastal, and inland waters with application to airborne measurements

CCPortal

DOI	10.1016/j.rse.2020.112155
	Spectral range within global aCDOM(440) algorithms for oceanic, coastal, and inland waters with application to airborne measurements
	Houskeeper H.F.; Hooker S.B.; Kudela R.M.
发表日期	2021
ISSN	00344257
卷号	253
英文摘要	The optically active component of dissolved organic material in aquatic ecosystems, or colored dissolved organic matter (CDOM), is represented by the coefficient of absorption due to the dissolved aquatic constituents at 440 nm, aCDOM(440). Remote sensing of aCDOM(440) enables characterization of ecosystem processes and aids in retrieval of chlorophyll a, a proxy for phytoplankton biomass. Spectrally adjacent band-ratio domains, e.g., blue to green, have previously been applied for remote sensing of aCDOM(440) in coastal and oceanic waters with similar results compared to more complex semi-analytical algorithms. Estimation of aCDOM(440) from ratios of the most spectrally separated ocean color wavebands (end members), e.g., ultraviolet (UV) to near-infrared (NIR), termed end-member analysis (EMA), has previously been shown to increase the accuracy of global aCDOM(440) retrievals from in-water observations of diffuse attenuation and to enable a unified algorithmic perspective without requiring regional adjustment of internal bio-optical parameters. EMA of above-water observations is evaluated herein, with a focus on coastal and inland waters in which increasing optical complexity and likelihood of bottom reflectance challenge the oceanic algorithms developed for deep and optically simple (case-1) waters. Analysis herein of three independent, in situ, bio-optical datasets indicates significant correlation between aCDOM(440) and end-member band ratios (next-generation 320 and 780 nm or legacy 412 and 670 nm ratios) with a coefficient of determination, R2, of 0.87 (log-scale) or higher based on a dataset spanning the dynamic range of global, conservative water bodies. For applicable wavelengths, EMA algorithms are shown to agree with case-1 relationships and to produce consistent log-scale uncertainties across more than three orders of magnitude in aCDOM(440) values (0.001–2.305 m−1). EMA using UV and NIR wavelengths (320 and 780 nm) is applied to low-altitude airborne observations and satisfies 25% uncertainty based on unbiased percent differences (UPDs) within each of three dissimilar match-up sites ranging in aCDOM(440) from 0.02–0.57 m−1. Results demonstrate that EMA is a useful and robust approach for the remote sensing of aCDOM(440) in coastal and inland waters, which are generally shallower, contain more optically complex environments, and span a greater range in aCDOM(440) than oceanic waters. © 2020 The Author(s)
英文关键词	Airborne; CDOM; Coastal zone; Inland waters; Open Ocean; Radiometry; Remote sensing; Spectral range
语种	英语
scopus关键词	Aquatic ecosystems; Dissolution; Infrared devices; Optical correlation; Airborne measurements; Airborne observations; Colored dissolved organic matter; Complex environments; Dissolved organic materials; Phytoplankton biomass; Semi-analytical algorithms; Three orders of magnitude; Remote sensing; accuracy assessment; airborne survey; algorithm; biomass; chlorophyll a; coastal water; complexity; dissolved organic matter; global change; ocean; ocean color; parameter estimation; phytoplankton; remote sensing; spectral analysis; spectral reflectance
来源期刊	Remote Sensing of Environment
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/179019
作者单位	Department of Geography, University of California, Los Angeles 315 Portola Plaza, Los Angeles, CA 90095, United States; Ocean Sciences Department, University of California, Santa Cruz 1156 High Street, Santa Cruz, CA 95064, United States; NASA Goddard Space Flight Center, Ocean Ecology Laboratory/Code 616.2, Greenbelt, MD 20771, United States
推荐引用方式 GB/T 7714	Houskeeper H.F.,Hooker S.B.,Kudela R.M.. Spectral range within global aCDOM(440) algorithms for oceanic, coastal, and inland waters with application to airborne measurements[J],2021,253.
APA	Houskeeper H.F.,Hooker S.B.,&Kudela R.M..(2021).Spectral range within global aCDOM(440) algorithms for oceanic, coastal, and inland waters with application to airborne measurements.Remote Sensing of Environment,253.
MLA	Houskeeper H.F.,et al."Spectral range within global aCDOM(440) algorithms for oceanic, coastal, and inland waters with application to airborne measurements".Remote Sensing of Environment 253(2021).