OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectances

This paper describes the selected algorithm for the ESA climate change initiative vegetation parameters project. Multi- and hyper-spectral, multi-angular, or multi-sensor top-of-canopy reflectance data call for an efficient generic retrieval system which can improve the consistent retrieval of stand...

Full description

Saved in:
Bibliographic Details
Main Authors: Simon Blessing, Ralf Giering, Christiaan van der Tol
Format: Article
Language:English
Published: Elsevier 2024-12-01
Series:Science of Remote Sensing
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2666017224000324
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1846127184147644416
author Simon Blessing
Ralf Giering
Christiaan van der Tol
author_facet Simon Blessing
Ralf Giering
Christiaan van der Tol
author_sort Simon Blessing
collection DOAJ
description This paper describes the selected algorithm for the ESA climate change initiative vegetation parameters project. Multi- and hyper-spectral, multi-angular, or multi-sensor top-of-canopy reflectance data call for an efficient generic retrieval system which can improve the consistent retrieval of standard canopy parameters as albedo, Leaf Area Index (LAI), Fraction of Absorbed Photosynthetically Active Radiation (fAPAR) and their uncertainties, and exploit the information to retrieve additional parameters (e.g. leaf pigments). We present a retrieval system for canopy and sub-canopy parameters (OptiSAIL), which is based on a model comprising SAIL (canopy reflectance), PROSPECT-D (leaf properties), TARTES (snow properties), a soil model (soil reflectance anisotropy, moisture effect), and a cloud contamination model. The inversion is gradient based and uses codes created by Automatic Differentiation. The full per pixel covariance-matrix of the retrieved parameters is computed. For this demonstration, single observation data from the Sentinel-3 SY_2_SYN (synergy) product is used. The results are compared with the MODIS 4-day LAI/fAPAR product and PhenoCam site photography. OptiSAIL produces generally consistent and credible results, at least matching the quality of the technically quite different MODIS product. The system is computationally efficient with a rate of 150 pixel s−1 (7 ms per pixel) for a single thread on a current desktop CPU using observations on 26 bands. Not all of the model parameters are well determined in all situations. Significant correlations between the parameters are found, which can change sign and magnitude over time. OptiSAIL appears to meet the design goals and puts real-time processing with this kind of system into reach.
format Article
id doaj-art-b5cde5fbf8764051b7bfecd93f8bf8a8
institution Kabale University
issn 2666-0172
language English
publishDate 2024-12-01
publisher Elsevier
record_format Article
series Science of Remote Sensing
spelling doaj-art-b5cde5fbf8764051b7bfecd93f8bf8a82024-12-12T05:23:04ZengElsevierScience of Remote Sensing2666-01722024-12-0110100148OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectancesSimon Blessing0Ralf Giering1Christiaan van der Tol2FastOpt GmbH, Lerchenstraße 28a, D-22767, Hamburg, Germany; Corresponding author.FastOpt GmbH, Lerchenstraße 28a, D-22767, Hamburg, GermanyFaculty of Geo-Information Science and Earth Observation (ITC), University of Twente, PO Box 217, 7500 AE, Enschede, The NetherlandsThis paper describes the selected algorithm for the ESA climate change initiative vegetation parameters project. Multi- and hyper-spectral, multi-angular, or multi-sensor top-of-canopy reflectance data call for an efficient generic retrieval system which can improve the consistent retrieval of standard canopy parameters as albedo, Leaf Area Index (LAI), Fraction of Absorbed Photosynthetically Active Radiation (fAPAR) and their uncertainties, and exploit the information to retrieve additional parameters (e.g. leaf pigments). We present a retrieval system for canopy and sub-canopy parameters (OptiSAIL), which is based on a model comprising SAIL (canopy reflectance), PROSPECT-D (leaf properties), TARTES (snow properties), a soil model (soil reflectance anisotropy, moisture effect), and a cloud contamination model. The inversion is gradient based and uses codes created by Automatic Differentiation. The full per pixel covariance-matrix of the retrieved parameters is computed. For this demonstration, single observation data from the Sentinel-3 SY_2_SYN (synergy) product is used. The results are compared with the MODIS 4-day LAI/fAPAR product and PhenoCam site photography. OptiSAIL produces generally consistent and credible results, at least matching the quality of the technically quite different MODIS product. The system is computationally efficient with a rate of 150 pixel s−1 (7 ms per pixel) for a single thread on a current desktop CPU using observations on 26 bands. Not all of the model parameters are well determined in all situations. Significant correlations between the parameters are found, which can change sign and magnitude over time. OptiSAIL appears to meet the design goals and puts real-time processing with this kind of system into reach.http://www.sciencedirect.com/science/article/pii/S2666017224000324Sentinel-3Synergy productOLCISLSTRTARTESPROSAIL
spellingShingle Simon Blessing
Ralf Giering
Christiaan van der Tol
OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectances
Science of Remote Sensing
Sentinel-3
Synergy product
OLCI
SLSTR
TARTES
PROSAIL
title OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectances
title_full OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectances
title_fullStr OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectances
title_full_unstemmed OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectances
title_short OptiSAIL: A system for the simultaneous retrieval of soil, leaf, and canopy parameters and its application to Sentinel-3 Synergy (OLCI+SLSTR) top-of-canopy reflectances
title_sort optisail a system for the simultaneous retrieval of soil leaf and canopy parameters and its application to sentinel 3 synergy olci slstr top of canopy reflectances
topic Sentinel-3
Synergy product
OLCI
SLSTR
TARTES
PROSAIL
url http://www.sciencedirect.com/science/article/pii/S2666017224000324
work_keys_str_mv AT simonblessing optisailasystemforthesimultaneousretrievalofsoilleafandcanopyparametersanditsapplicationtosentinel3synergyolcislstrtopofcanopyreflectances
AT ralfgiering optisailasystemforthesimultaneousretrievalofsoilleafandcanopyparametersanditsapplicationtosentinel3synergyolcislstrtopofcanopyreflectances
AT christiaanvandertol optisailasystemforthesimultaneousretrievalofsoilleafandcanopyparametersanditsapplicationtosentinel3synergyolcislstrtopofcanopyreflectances