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Efficient modeling of sun/shade canopy radiation dynamics explicitly accounting for scattering

Bodin, Per LU and Franklin, Oskar (2012) In Geoscientific Model Development 5(2). p.535-541
Abstract (Swedish)
Abstract in Undetermined

The separation of global radiation (Rg) into its direct (Rb) and diffuse constituents (Rg) is important when modeling plant photosynthesis because a high Rd:Rg ratio has been shown to enhance Gross Primary Production (GPP). To include this effect in vegetation models, the plant canopy must be separated into sunlit and shaded leaves. However, because such models are often too intractable and computationally expensive for theoretical or large scale studies, simpler sun-shade approaches are often preferred. A widely used and computationally efficient sun-shade model was developed by Goudriaan (1977) (GOU). However, compared to more complex models, this model's realism is limited by its lack of explicit... (More)
Abstract in Undetermined

The separation of global radiation (Rg) into its direct (Rb) and diffuse constituents (Rg) is important when modeling plant photosynthesis because a high Rd:Rg ratio has been shown to enhance Gross Primary Production (GPP). To include this effect in vegetation models, the plant canopy must be separated into sunlit and shaded leaves. However, because such models are often too intractable and computationally expensive for theoretical or large scale studies, simpler sun-shade approaches are often preferred. A widely used and computationally efficient sun-shade model was developed by Goudriaan (1977) (GOU). However, compared to more complex models, this model's realism is limited by its lack of explicit treatment of radiation scattering.



Here we present a new model based on the GOU model, but which in contrast explicitly simulates radiation scattering by sunlit leaves and the absorption of this radiation by the canopy layers above and below (2-stream approach). Compared to the GOU model our model predicts significantly different profiles of scattered radiation that are in better agreement with measured profiles of downwelling diffuse radiation. With respect to these data our model's performance is equal to a more complex and much slower iterative radiation model while maintaining the simplicity and computational efficiency of the GOU model. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Geoscientific Model Development
volume
5
issue
2
pages
535 - 541
publisher
Copernicus Gesellschaft Mbh
external identifiers
  • wos:000304060600016
  • scopus:84881127567
ISSN
1991-959X
DOI
10.5194/gmd-5-535-2012
project
BECC
MERGE
language
English
LU publication?
yes
id
9f725c56-201d-4b98-b81e-295464a570ca (old id 2520380)
alternative location
http://www.geosci-model-dev.net/5/535/2012/gmd-5-535-2012.pdf
date added to LUP
2012-06-20 10:22:02
date last changed
2017-05-14 03:20:53
@article{9f725c56-201d-4b98-b81e-295464a570ca,
  abstract     = {<b>Abstract in Undetermined</b><br/><br>
The separation of global radiation (Rg) into its direct (Rb) and diffuse constituents (Rg) is important when modeling plant photosynthesis because a high Rd:Rg ratio has been shown to enhance Gross Primary Production (GPP). To include this effect in vegetation models, the plant canopy must be separated into sunlit and shaded leaves. However, because such models are often too intractable and computationally expensive for theoretical or large scale studies, simpler sun-shade approaches are often preferred. A widely used and computationally efficient sun-shade model was developed by Goudriaan (1977) (GOU). However, compared to more complex models, this model's realism is limited by its lack of explicit treatment of radiation scattering. <br/><br>
<br/><br>
Here we present a new model based on the GOU model, but which in contrast explicitly simulates radiation scattering by sunlit leaves and the absorption of this radiation by the canopy layers above and below (2-stream approach). Compared to the GOU model our model predicts significantly different profiles of scattered radiation that are in better agreement with measured profiles of downwelling diffuse radiation. With respect to these data our model's performance is equal to a more complex and much slower iterative radiation model while maintaining the simplicity and computational efficiency of the GOU model.},
  author       = {Bodin, Per and Franklin, Oskar},
  issn         = {1991-959X},
  language     = {eng},
  number       = {2},
  pages        = {535--541},
  publisher    = {Copernicus Gesellschaft Mbh},
  series       = {Geoscientific Model Development},
  title        = {Efficient modeling of sun/shade canopy radiation dynamics explicitly accounting for scattering},
  url          = {http://dx.doi.org/10.5194/gmd-5-535-2012},
  volume       = {5},
  year         = {2012},
}