A Universal Fuzzy Logic Optical Water Type Scheme for the Global Oceans

The classification of natural waters is a way to generalize and systematize ocean color science. However, there is no consensus on an optimal water classification template in many contexts. In this study, we conducted an unsupervised classification of the PACE (Plankton, Aerosols, Cloud, and Ocean E...

Full description

Bibliographic Details
Main Authors: Tianxia Jia, Yonglin Zhang, Rencai Dong
Format: Article
Language:English
Published: MDPI AG 2021-10-01
Series:Remote Sensing
Subjects:
Online Access:https://www.mdpi.com/2072-4292/13/19/4018
_version_ 1797515806488133632
author Tianxia Jia
Yonglin Zhang
Rencai Dong
author_facet Tianxia Jia
Yonglin Zhang
Rencai Dong
author_sort Tianxia Jia
collection DOAJ
description The classification of natural waters is a way to generalize and systematize ocean color science. However, there is no consensus on an optimal water classification template in many contexts. In this study, we conducted an unsupervised classification of the PACE (Plankton, Aerosols, Cloud, and Ocean Ecosystem) synthetic hyperspectral data set, divided the global ocean waters into 15 classes, then obtained a set of fuzzy logic optical water type schemes (abbreviated as the U-OWT in this study) that were tailored for several multispectral satellite sensors, including SeaWiFS, MERIS, MODIS, OLI, VIIRS, MSI, and OLCI. The consistency analysis showed that the performance of U-OWT on different satellite sensors was comparable, and the sensitivity analysis demonstrated the U-OWT could resist a certain degree of input disturbance on remote sensing reflectance. Compared to existing ocean-aimed optical water type schemes, the U-OWT can distinguish more mesotrophic and eutrophic water classes. Furthermore, the U-OWT was highly compatible with other water classification taxonomies, including the trophic state index, the multivariate absorption combinations, and the Forel-Ule Scale, which indirectly demonstrated the potential for global applicability of the U-OWT. This finding was also helpful for the further conversion and unification of different water type taxonomies. As the fundamental basis, the U-OWT can be applied to many oceanic fields that need to be explored in the future. To promote the reproducibility of this study, an IDL<sup>®</sup>-based standalone U-OWT calculation tool is freely distributed.
first_indexed 2024-03-10T06:52:28Z
format Article
id doaj.art-c6b72fc1a2bf4e70ace1d7d001105fbe
institution Directory Open Access Journal
issn 2072-4292
language English
last_indexed 2024-03-10T06:52:28Z
publishDate 2021-10-01
publisher MDPI AG
record_format Article
series Remote Sensing
spelling doaj.art-c6b72fc1a2bf4e70ace1d7d001105fbe2023-11-22T16:44:17ZengMDPI AGRemote Sensing2072-42922021-10-011319401810.3390/rs13194018A Universal Fuzzy Logic Optical Water Type Scheme for the Global OceansTianxia Jia0Yonglin Zhang1Rencai Dong2State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, ChinaState Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, ChinaState Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, ChinaThe classification of natural waters is a way to generalize and systematize ocean color science. However, there is no consensus on an optimal water classification template in many contexts. In this study, we conducted an unsupervised classification of the PACE (Plankton, Aerosols, Cloud, and Ocean Ecosystem) synthetic hyperspectral data set, divided the global ocean waters into 15 classes, then obtained a set of fuzzy logic optical water type schemes (abbreviated as the U-OWT in this study) that were tailored for several multispectral satellite sensors, including SeaWiFS, MERIS, MODIS, OLI, VIIRS, MSI, and OLCI. The consistency analysis showed that the performance of U-OWT on different satellite sensors was comparable, and the sensitivity analysis demonstrated the U-OWT could resist a certain degree of input disturbance on remote sensing reflectance. Compared to existing ocean-aimed optical water type schemes, the U-OWT can distinguish more mesotrophic and eutrophic water classes. Furthermore, the U-OWT was highly compatible with other water classification taxonomies, including the trophic state index, the multivariate absorption combinations, and the Forel-Ule Scale, which indirectly demonstrated the potential for global applicability of the U-OWT. This finding was also helpful for the further conversion and unification of different water type taxonomies. As the fundamental basis, the U-OWT can be applied to many oceanic fields that need to be explored in the future. To promote the reproducibility of this study, an IDL<sup>®</sup>-based standalone U-OWT calculation tool is freely distributed.https://www.mdpi.com/2072-4292/13/19/4018ocean colorwater type taxonomiestrophic stateinherent optical propertiesForel-Ule Scale
spellingShingle Tianxia Jia
Yonglin Zhang
Rencai Dong
A Universal Fuzzy Logic Optical Water Type Scheme for the Global Oceans
Remote Sensing
ocean color
water type taxonomies
trophic state
inherent optical properties
Forel-Ule Scale
title A Universal Fuzzy Logic Optical Water Type Scheme for the Global Oceans
title_full A Universal Fuzzy Logic Optical Water Type Scheme for the Global Oceans
title_fullStr A Universal Fuzzy Logic Optical Water Type Scheme for the Global Oceans
title_full_unstemmed A Universal Fuzzy Logic Optical Water Type Scheme for the Global Oceans
title_short A Universal Fuzzy Logic Optical Water Type Scheme for the Global Oceans
title_sort universal fuzzy logic optical water type scheme for the global oceans
topic ocean color
water type taxonomies
trophic state
inherent optical properties
Forel-Ule Scale
url https://www.mdpi.com/2072-4292/13/19/4018
work_keys_str_mv AT tianxiajia auniversalfuzzylogicopticalwatertypeschemefortheglobaloceans
AT yonglinzhang auniversalfuzzylogicopticalwatertypeschemefortheglobaloceans
AT rencaidong auniversalfuzzylogicopticalwatertypeschemefortheglobaloceans
AT tianxiajia universalfuzzylogicopticalwatertypeschemefortheglobaloceans
AT yonglinzhang universalfuzzylogicopticalwatertypeschemefortheglobaloceans
AT rencaidong universalfuzzylogicopticalwatertypeschemefortheglobaloceans