Details

Autor(en) / Beteiligte

• Tan, Shen
• Wang, Han
• Prentice, Iain. Colin
• Yang, Kun
• Nóbrega, Rodolfo. L.B.
• Liu, Xiaomang
• Wang, Yong
• Yang, Yuting

Titel

Towards a universal evapotranspiration model based on optimality principles

Ist Teil von

• Agricultural and forest meteorology, 2023-06, Vol.336, p.109478, Article 109478

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• •In this study, we.•estimate GPP and ET based on EEO principles, with no type-specific parameters;.•test ET model at site, basin, and global scales systematically;.•demonstrate the universal model has a comparable performance with other products. Natural resource management requires knowledge of terrestrial evapotranspiration (ET). Most existing numeric models for ET include multiple plant- or ecosystem-type specific parameters that require calibration. This is a significant source of uncertainty under changing environmental conditions. A novel ET model with no type−specific parameters was developed recently. Based on the coupling the diffusion (via stomata) of water and carbon dioxide (CO2), this model predicts canopy conductance based on environmental conditions using eco-evolutionary optimality principles that apply to all plant types. Transpiration (T) and ET are calculated from canopy conductance using the Penman-Monteith equation for T and a universal empirical function for the T:ET ratio. Here, the model is systematically evaluated at globally distributed eddy-covariance sites and river basins. Site-scale modelled ET agrees well with flux data (r = 0.81, root mean square error = 0.73 mm day–1 in 23,623 records) and modelled ET in 39 river basins agrees well with the ET estimated by monthly water budget using two runoff datasets (r = 0.62 and 0.66, respectively). Modelled global patterns of ET are consistent with existing global ET products. The model's universality, parsimony and accuracy combine to indicate a broad potential field of application in resource management and global change science.