A Caltech Library Service

Accounting for canopy structure improves hyperspectral radiative transfer and sun-induced chlorophyll fluorescence representations in a new generation Earth System model

Braghiere, Renato K. and Wang, Yujie and Doughty, Russell and Sousa, Daniel and Magney, Troy and Widlowski, Jean-Luc and Longo, Marcos and Bloom, A. Anthony and Worden, John and Gentine, Pierre and Frankenberg, Christian (2021) Accounting for canopy structure improves hyperspectral radiative transfer and sun-induced chlorophyll fluorescence representations in a new generation Earth System model. Remote Sensing of Environment, 261 . Art. No. 112497. ISSN 0034-4257. doi:10.1016/j.rse.2021.112497.

[img] PDF (Supplementary data) - Supplemental Material
See Usage Policy.


Use this Persistent URL to link to this item:


Three-dimensional (3D) vegetation canopy structure plays an important role in the way radiation interacts with the land surface. Accurately representing this process in Earth System models (ESMs) is crucial for the modeling of the global carbon, energy, and water cycles and hence future climate projections. Despite the importance of accounting for 3D canopy structure, the inability to represent such complexity at regional and global scales has impeded a successful implementation into ESMs. An alternative approach is to use an implicit clumping index to account for the horizontal heterogeneity in vegetation canopy representations in ESMs at global scale. This paper evaluates how modeled hyperspectral shortwave radiation partitioning of the terrestrial biosphere, as well as Sun-Induced Chlorophyll Fluorescence (SIF) are impacted when a clumping index parameterization is incorporated in the radiative transfer scheme of a new generation ESM, the Climate Model Alliance (CliMA). An accurate hyperspectral radiative transfer representation within ESMs is critical for accurately using of satellite data to confront, constrain, and improve land model processes. The newly implemented scheme is compared to Monte Carlo calculations for idealized scenes from the Radiation transfer Model Intercomparison for the Project for Intercomparison of Land-Surface Parameterizations (RAMI4PILPS), for open forest canopies both with and without snow on the ground. Results indicate that it is critical to account for canopy structural heterogeneity when calculating hyperspectral radiation transfer. The RMSE in shortwave radiation is reduced for reflectance (25%), absorptance (66%), and transmittance (75%) compared to the scenario without considering clumping. Calculated SIF is validated against satellite remote sensing data with the recently launched NASA Orbiting Carbon Observatory (OCO) 3, showing that including vertical and horizontal canopy structure when deriving SIF can improve model predictions in up to 51% in comparison to the scenario without clumping. By adding a clumping index into the CliMA-Land model, the relationship between canopy structure and SIF, Gross Primary Productivity (GPP), hyperspectral radiative transfer, and viewing geometry at the canopy scale can be explored in detail.

Item Type:Article
Related URLs:
URLURL TypeDescription
Wang, Yujie0000-0002-3729-2743
Magney, Troy0000-0002-9033-0024
Longo, Marcos0000-0001-5062-6245
Worden, John0000-0003-0257-9549
Gentine, Pierre0000-0002-0845-8345
Frankenberg, Christian0000-0002-0546-5857
Additional Information:© 2021 Published by Elsevier Inc. Received 25 December 2020, Revised 30 April 2021, Accepted 7 May 2021, Available online 13 May 2021. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. California Institute of Technology. Government sponsorship acknowledged. Copyright 2021. All rights reserved. TSM and CF are supported by the National Aeronautics and Space Administration (80NSSC19M0129) and the National Science Foundation, through the Macrosystems Biology and NEON Enabled Science Program (DEB579 1926090). Part of this research was funded by Eric and Wendy Schmidt by recommendation of the Schmidt Futures program, and by Hopewell Fund. RD is supported by NASA Making Earth System Data Records for Use in Research Environments (MEaSUREs) Program (NNN12AA01C) and OCO-2/3 Science Team (80NSSC18K0895). We would like to thank Nick Parazoo for sharing model runs from the SIF-enabled LSMs for Niwot Ridge. We thank the editors and three anonymous reviewers whose suggestions helped improve this manuscript. Description of author's responsibilities: RKB: conceptualization, methodology, formal analysis, writing - original draft, writing - review & editing, implementation of clumping index, research; RKB and YW: spectral properties fitting package, model coding, and writing; RKB and RD: OCO-3 SIF methodology and writing; DS: soil spectral properties for Niwot Ridge; TM and JLW: validation datasets and editing; ML, AB, JW, PG: editing and model conceptualization; CF: model conceptualization, coding, review, and editing. The authors declare no competing interests.
Funding AgencyGrant Number
Schmidt Futures ProgramUNSPECIFIED
Subject Keywords:Canopy structure; Sun-induced chlorophyll fluorescence; Hyperspectral radiative transfer scheme; Earth System models; Energy balance; Carbon cycle; NASA orbiting carbon observatory 3
Record Number:CaltechAUTHORS:20210517-144643534
Persistent URL:
Official Citation:Renato K. Braghiere, Yujie Wang, Russell Doughty, Daniel Sousa, Troy Magney, Jean-Luc Widlowski, Marcos Longo, A. Anthony Bloom, John Worden, Pierre Gentine, Christian Frankenberg, Accounting for canopy structure improves hyperspectral radiative transfer and sun-induced chlorophyll fluorescence representations in a new generation Earth System model, Remote Sensing of Environment, Volume 261, 2021, 112497, ISSN 0034-4257,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:109157
Deposited By: Tony Diaz
Deposited On:17 May 2021 22:29
Last Modified:17 May 2021 22:29

Repository Staff Only: item control page