Incorporating the Acclimation of Photosynthesis and Leaf Respiration in the Noah‐MP Land Surface Model: Model Development and Evaluation

Journal Article · 05 March 2025 · Journal of Advances in Modeling Earth Systems

DOI: https://doi.org/10.1029/2024MS004599 · OSTI ID:2530640

Ren, Yanghang ^[1]; Wang, Han  ^[1]; Harrison, Sandy P.  ^[2]; Prentice, I. Colin ^[3]; Mengoli, Giulia ^[4]; Zhao, Long  ^[5]; Reich, Peter B. ^[6]; Yang, Kun  ^[1]

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1. Department of Earth System Science Ministry of Education Key Laboratory for Earth System Modeling Institute for Global Change Studies Tsinghua University Beijing China
2. Department of Earth System Science Ministry of Education Key Laboratory for Earth System Modeling Institute for Global Change Studies Tsinghua University Beijing China, School of Archaeology Geography and Environmental Sciences (SAGES) University of Reading Reading UK
3. Department of Earth System Science Ministry of Education Key Laboratory for Earth System Modeling Institute for Global Change Studies Tsinghua University Beijing China, Department of Life Sciences Georgina Mace Centre for the Living Planet Imperial College London Silwood Park Campus Ascot UK
4. Department of Life Sciences Georgina Mace Centre for the Living Planet Imperial College London Silwood Park Campus Ascot UK
5. Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical Sciences Southwest University Chongqing China
6. Department of Forest Resources University of Minnesota St. Paul MN USA, Institute for Global Change Biology, and School for the Environment and Sustainability University of Michigan Ann Arbor MI USA, Hawkesbury Institute for the Environment Western Sydney University Penrith NSW Australia

Abstract Realistic simulation of leaf photosynthetic and respiratory processes is needed for accurate prediction of the global carbon cycle. These two processes systematically acclimate to long‐term environmental changes by adjusting photosynthetic and respiratory traits (e.g., the maximum photosynthetic capacity at 25°C ( V _cmax,25 ) and the leaf respiration rate at 25°C ( R ₂₅ )) following increasingly well‐understood principles. While some land surface models (LSMs) now account for thermal acclimation, they do so by assigning empirical parameterizations for individual plant functional types (PFTs). Here, we have implemented an Eco‐Evolutionary Optimality (EEO)‐based scheme to represent the universal acclimation of photosynthesis and leaf respiration to multiple environmental effects, and that therefore requires no PFT‐specific parameterizations, in a standard version of the widely used LSM, Noah MP. We evaluated model performance with plant trait data from a 5‐year experiment and extensive global field measurements, and carbon flux measurements from FLUXNET2015. We show that observed R ₂₅ and V _cmax,25 vary substantially both temporally and spatially within the same PFT ( C.V. >20%). Our EEO‐based scheme captures 62% of the temporal and 70% of the spatial variations in V _cmax,25 (73% and 54% of the variations in R ₂₅ ). The standard scheme underestimates gross primary production by 10% versus 2% for the EEO‐based scheme and generates a larger spread in r (correlation coefficient) across flux sites (0.79 ± 0.16 vs. 0.84 ± 0.1, mean ± S.D.). The standard scheme greatly overestimates canopy respiration (bias: ∼200% vs. 8% for the EEO scheme), resulting in less CO ₂ uptake by terrestrial ecosystems. Our approach thus simulates climate‐carbon coupling more realistically, with fewer parameters.

• Sponsoring Organization: USDOE
• OSTI ID: 2530640
• Journal Information: Journal of Advances in Modeling Earth Systems, Journal Name: Journal of Advances in Modeling Earth Systems Journal Issue: 3 Vol. 17; ISSN 1942-2466
• Publisher: American Geophysical Union (AGU)Copyright Statement
• Country of Publication: United States
• Language: English