Stepwise Calibration of Age-Dependent Biomass in the Integrated Biosphere Simulator (IBIS) Model - CEA - Université Paris-Saclay Accéder directement au contenu
Article Dans Une Revue Journal of Advances in Modeling Earth Systems Année : 2024

Stepwise Calibration of Age-Dependent Biomass in the Integrated Biosphere Simulator (IBIS) Model

Résumé

© 2024 The Author(s). Journal of Advances in Modeling Earth Systems published by Wiley Periodicals LLC on behalf of American Geophysical Union.Many land surface models (LSMs) assume a steady-state assumption (SS) for forest growth, leading to an overestimation of biomass in young forests. Parameters inversion under SS will potentially result in biased carbon fluxes and stocks in a transient simulation. Incorporating age-dependent biomass into LSMs can simulate real disequilibrium states, enabling the model to simulate forest growth from planting to its current age, and improving the biased post-calibration parameters. In this study, we developed a stepwise optimization framework that first calibrates u201cfastu201d light-controlled CO2 fluxes (gross primary productivity, GPP), then leaf area index (LAI), and finally u201cslowu201d growth-controlled biomass using the Global LAnd Surface Satellite (GLASS) GPP and LAI products, and age-dependent biomass curves for the 25 forests. To reduce the computation time, we used a machine learning-based model to surrogate the complex integrated biosphere simulator LSM during calibration. Our calibrated model led to an error reduction in GPP, LAI, and biomass by 28.5%, 35.3% and 74.6%, respectively. When compared with net biome productivity (NBP) using no-age-calibrated parameters, our age-calibrated parameters increased NBP by an average of 50 gC m−2 yr−1 across all forests, especially in the boreal needleleaf evergreen forests, the NBP increased by 118 gC m−2 yr−1 on average, increasing the estimate of the carbon sink in young forests. Our work highlights the importance of including forest age in LSMs, and provides a novel framework for better calibrating LSMs using constraints from multiple satellite products at a global scale.
Fichier principal
Vignette du fichier
J Adv Model Earth Syst - 2024 - Ma - Stepwise Calibration of Age‐Dependent Biomass in the Integrated Biosphere Simulator .pdf (2.22 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-04616728 , version 1 (21-06-2024)

Licence

Identifiants

Citer

Rui Ma, Philippe Ciais, Yidi Xu, Daniel Goll, Yuan Zhang, et al.. Stepwise Calibration of Age-Dependent Biomass in the Integrated Biosphere Simulator (IBIS) Model. Journal of Advances in Modeling Earth Systems, 2024, 16 (6), ⟨10.1029/2023MS004048⟩. ⟨hal-04616728⟩
0 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More