Author
PARRY, CHRISTOPHER | |
NIETO, HECTOR - INSTITUTE DE RECERCA I TECNOLOGIA AGROALIMENTARIES (IRTA) | |
GUILLEVIC, PIERRE - UNIVERSITY OF MARYLAND | |
AGAM, NURIT - BEN GURION UNIVERSITY OF NEGEV | |
Kustas, William - Bill | |
Alfieri, Joseph | |
McKee, Lynn | |
McElrone, Andrew |
Submitted to: Irrigation Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/23/2019 Publication Date: 2/8/2019 Citation: Parry, C.K., Nieto, H., Guillevic, P., Agam, N., Kustas, W.P., Alfieri, J.G., McKee, L.G., McElrone, A.J. 2019. An intercomparison of radiation partitioning models in vineyard canopies. Irrigation Science. 37(3):239-252. https://doi.org/10.1007/s00271-019-00621-x. DOI: https://doi.org/10.1007/s00271-019-00621-x Interpretive Summary: Multiple radiation transfer models with unique clumping indices (a total of five approaches) were evaluated on two Pinot Noir vineyards in Central California over three years. In the first approach, a basic clumping index meant for heterogeneous randomly-placed clumped canopies was combined with the Campbell & Norman transfer model (C&N-H). The other four approaches, namely the Campbell & Norman with rectangular hedgerow clumping index (C&N-R), Campbell & Norman with a geometric elliptical hedgerow model (C&N-E), 4SAIL with row crop clumping index, and the Discrete Anisotropic Radiative Transfer (DART) models account for the unique canopy coverage distribution of the vineyard row structured canopies. Each modelling approach varied in its complexity to predict transmitted solar radiation at ground level and the outputs were compared to solar radiation measured at the surface with an array of pyranometers. All five modelling approaches showed good agreement with the measured values (correlation coefficients (r) ranged from 0.95 to 0.97). Model performance varied throughout the season due to their sensitivity to canopy growth. Although r values showed good agreement among all approaches, the C&N-E and DART models showed a better “goodness of fit” with lower root mean squared and bias values. Technical Abstract: Multiple radiation transfer models with unique clumping indices (a total of five approaches) were evaluated on two Pinot Noir vineyards in Central California over three years. In the first approach, a basic clumping index meant for heterogeneous randomly-placed clumped canopies was combined with the Campbell & Norman transfer model (C&N-H). The other four approaches, namely the Campbell & Norman with rectangular hedgerow clumping index (C&N-R), Campbell & Norman with a geometric elliptical hedgerow model (C&N-E), 4SAIL with row crop clumping index, and the Discrete Anisotropic Radiative Transfer (DART) models account for the unique canopy coverage distribution of the vineyard row structured canopies. Each modelling approach varied in its complexity to predict transmitted solar radiation at ground level and the outputs were compared to solar radiation measured at the surface with an array of pyranometers. All five modelling approaches showed good agreement with the measured values (correlation coefficients (r) ranged from 0.95 to 0.97). Model performance varied throughout the season due to their sensitivity to canopy growth. Although r values showed good agreement among all approaches, the C&N-E and DART models showed a better “goodness of fit” with lower root mean squared and bias values. |