Radiation fluxes and canopy transmittance

Models and measurements inside a willow canopy

Matti Mõttus, Madis Sulev

Research output: Contribution to journalArticleScientificpeer-review

3 Citations (Scopus)

Abstract

Upward and downward fluxes of photosynthetically active and broadband solar radiation, and the transmittance of direct solar radiation measured at different heights inside a willow (Salix viminalis) canopy are compared with modeling results. Two approaches are used for modeling the radiation field inside the canopy: solving the radiative transfer equation using the exact kernel discrete ordinates method and a Monte Carlo model. The measured and modeled canopies include a 1-year-old willow coppice with leaf area index (LAI) = 5 and a 4-year-old coppice with LAI = 8. Biometrical data used in the models are taken from detailed measurements of canopy structure; measured fluxes are used as boundary conditions. An attempt is made to include the effect of clumping on the penetration of direct solar radiation into the radiative transfer model. All models agreed well with measurement results; enhancement of modeled fluxes due to inclusion of clumping depended on the height inside the canopy while the distribution of leaf inclination angle had a minimal effect on the radiation regime of the stand.

Original languageEnglish
Article numberD02109
JournalJournal of Geophysical Research: Atmospheres
Volume111
Issue number2
DOIs
Publication statusPublished - 27 Jan 2006
MoE publication typeA1 Journal article-refereed

Fingerprint

Salix
canopies
transmittance
Solar radiation
canopy
Fluxes
Radiation
solar radiation
Radiative transfer
leaf area index
radiation
coppice
radiative transfer
Salix viminalis
leaf angle
radiation distribution
leaves
modeling
Boundary conditions
inclination

Cite this

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Radiation fluxes and canopy transmittance : Models and measurements inside a willow canopy. / Mõttus, Matti; Sulev, Madis.

In: Journal of Geophysical Research: Atmospheres, Vol. 111, No. 2, D02109, 27.01.2006.

Research output: Contribution to journalArticleScientificpeer-review

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AU - Sulev, Madis

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