Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals
While solar-induced fluorescence (SIF) shows promise as a remotely-sensed measurement directly related to photosynthesis, interpretation and validation of satellite-based SIF retrievals remains a challenge. SIF is influenced by the fraction of absorbed photosynthetically-active radiation at the cano...
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Format: | Article |
Language: | English |
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MDPI AG
2020-07-01
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Series: | Remote Sensing |
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Online Access: | https://www.mdpi.com/2072-4292/12/15/2346 |
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record_format |
Article |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Joanna Joiner Yasuko Yoshida Philipp Köehler Petya Campbell Christian Frankenberg Christiaan van der Tol Peiqi Yang Nicholas Parazoo Luis Guanter Ying Sun |
spellingShingle |
Joanna Joiner Yasuko Yoshida Philipp Köehler Petya Campbell Christian Frankenberg Christiaan van der Tol Peiqi Yang Nicholas Parazoo Luis Guanter Ying Sun Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals Remote Sensing solar-induced fluorescence satellite remote sensing SIF reflectance GOME-2 TROPOMI |
author_facet |
Joanna Joiner Yasuko Yoshida Philipp Köehler Petya Campbell Christian Frankenberg Christiaan van der Tol Peiqi Yang Nicholas Parazoo Luis Guanter Ying Sun |
author_sort |
Joanna Joiner |
title |
Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals |
title_short |
Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals |
title_full |
Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals |
title_fullStr |
Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals |
title_full_unstemmed |
Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals |
title_sort |
systematic orbital geometry-dependent variations in satellite solar-induced fluorescence (sif) retrievals |
publisher |
MDPI AG |
series |
Remote Sensing |
issn |
2072-4292 |
publishDate |
2020-07-01 |
description |
While solar-induced fluorescence (SIF) shows promise as a remotely-sensed measurement directly related to photosynthesis, interpretation and validation of satellite-based SIF retrievals remains a challenge. SIF is influenced by the fraction of absorbed photosynthetically-active radiation at the canopy level that depends upon illumination geometry as well as the escape of SIF through the canopy that depends upon the viewing geometry. Several approaches to estimate the effects of sun-sensor geometry on satellite-based SIF have been proposed, and some have been implemented, most relying upon satellite reflectance measurements and/or other ancillary data sets. These approaches, designed to ultimately estimate intrinsic or physiological components of SIF related to photosynthesis, have not generally been applied globally to satellite measurements. Here, we examine in detail how SIF and related reflectance-based indices from wide swath polar orbiting satellites in low Earth orbit vary systematically due to the host satellite orbital characteristics. We compare SIF and reflectance-based parameters from the Global Ozone Mapping Experiment 2 (GOME-2) on the MetOp-B platform and from the TROPOspheric Monitoring Instrument (TROPOMI) on the Sentinel 5 Precursor satellite with a focus on high northern latitudes in summer where observations at similar geometries and local times occur. We show that GOME-2 and TROPOMI SIF observations agree nearly to within estimated uncertainties when they are compared at similar observing geometries. We show that the cross-track dependence of SIF normalized by PAR and related reflectance-based indices are highly correlated for dense canopies, but diverge substantially as the vegetation within a field-of-view becomes more sparse. This has implications for approaches that utilize reflectance measurements to help account for SIF geometrical dependences in satellite measurements. To further help interpret the GOME-2 and TROPOMI SIF observations, we simulated cross-track dependences of PAR normalized SIF and reflectance-based indices with the one dimensional Soil-Canopy Observation Photosynthesis and Energy fluxes (SCOPE) canopy radiative transfer model at sun–satellite geometries that occur across the wide swaths of these instruments and examine the geometrical dependencies of the various components (e.g., fraction of absorbed PAR, SIF yield, and escape of SIF from the canopy) of the observed SIF signal. The simulations show that most of the cross-track variations in SIF result from the escape of SIF through the scattering canopy and not the illumination. |
topic |
solar-induced fluorescence satellite remote sensing SIF reflectance GOME-2 TROPOMI |
url |
https://www.mdpi.com/2072-4292/12/15/2346 |
work_keys_str_mv |
AT joannajoiner systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT yasukoyoshida systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT philippkoehler systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT petyacampbell systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT christianfrankenberg systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT christiaanvandertol systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT peiqiyang systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT nicholasparazoo systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT luisguanter systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals AT yingsun systematicorbitalgeometrydependentvariationsinsatellitesolarinducedfluorescencesifretrievals |
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1724750023736950784 |
spelling |
doaj-8f389522b7eb4e3aa4e9e1ce892989aa2020-11-25T02:48:06ZengMDPI AGRemote Sensing2072-42922020-07-01122346234610.3390/rs12152346Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) RetrievalsJoanna Joiner0Yasuko Yoshida1Philipp Köehler2Petya Campbell3Christian Frankenberg4Christiaan van der Tol5Peiqi Yang6Nicholas Parazoo7Luis Guanter8Ying Sun9National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC), Greenbelt, MD 20771, USAScience Systems and Applications, Inc. (SSAI), Lanham, MD 20706, USADivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91109, USAJoint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, MD 21250, USADivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91109, USAFaculty of Geo-Information Science and Earth Observation (ITC), University of Twente, P.O. Box 6, 7500 AE Enschede, The NetherlandsFaculty of Geo-Information Science and Earth Observation (ITC), University of Twente, P.O. Box 6, 7500 AE Enschede, The NetherlandsJet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USACentro de Tecnologías Físicas, Universitat Politècnica de València, València, Camí de Vera s/n, 46022 València, SpainUnit of Soil and Crop Sciences, School of Integrated Plant Sciences, Cornell University, Ithaca, NY 14853, USAWhile solar-induced fluorescence (SIF) shows promise as a remotely-sensed measurement directly related to photosynthesis, interpretation and validation of satellite-based SIF retrievals remains a challenge. SIF is influenced by the fraction of absorbed photosynthetically-active radiation at the canopy level that depends upon illumination geometry as well as the escape of SIF through the canopy that depends upon the viewing geometry. Several approaches to estimate the effects of sun-sensor geometry on satellite-based SIF have been proposed, and some have been implemented, most relying upon satellite reflectance measurements and/or other ancillary data sets. These approaches, designed to ultimately estimate intrinsic or physiological components of SIF related to photosynthesis, have not generally been applied globally to satellite measurements. Here, we examine in detail how SIF and related reflectance-based indices from wide swath polar orbiting satellites in low Earth orbit vary systematically due to the host satellite orbital characteristics. We compare SIF and reflectance-based parameters from the Global Ozone Mapping Experiment 2 (GOME-2) on the MetOp-B platform and from the TROPOspheric Monitoring Instrument (TROPOMI) on the Sentinel 5 Precursor satellite with a focus on high northern latitudes in summer where observations at similar geometries and local times occur. We show that GOME-2 and TROPOMI SIF observations agree nearly to within estimated uncertainties when they are compared at similar observing geometries. We show that the cross-track dependence of SIF normalized by PAR and related reflectance-based indices are highly correlated for dense canopies, but diverge substantially as the vegetation within a field-of-view becomes more sparse. This has implications for approaches that utilize reflectance measurements to help account for SIF geometrical dependences in satellite measurements. To further help interpret the GOME-2 and TROPOMI SIF observations, we simulated cross-track dependences of PAR normalized SIF and reflectance-based indices with the one dimensional Soil-Canopy Observation Photosynthesis and Energy fluxes (SCOPE) canopy radiative transfer model at sun–satellite geometries that occur across the wide swaths of these instruments and examine the geometrical dependencies of the various components (e.g., fraction of absorbed PAR, SIF yield, and escape of SIF from the canopy) of the observed SIF signal. The simulations show that most of the cross-track variations in SIF result from the escape of SIF through the scattering canopy and not the illumination.https://www.mdpi.com/2072-4292/12/15/2346solar-induced fluorescencesatellite remote sensingSIFreflectanceGOME-2TROPOMI |