Characterizing Performance of Freshwater Wetland Methane Models Across Time Scales at FLUXNET-CH₄ Sites Using Wavelet Analyses ...

• Main Authors: Zhang, Zhen, Bansal, Sheel, Chang, Kuang-Yu, Fluet-Chouinard, Etienne, Delwiche, Kyle, Goeckede, Mathias, Gustafson, Adrian, Knox, Sara, Leppänen, Antti, Liu, Licheng, Liu, Jinxun, Malhotra, Avni, Markkanen, Tiina, McNicol, Gavin, Melton, Joe R., Miller, Paul A., Peng, Changhui, Raivonen, Maarit, Riley, William J., Sonnentag, Oliver
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2023
• Subjects: Arctic; Tundra
• Online Access: https://dx.doi.org/10.3929/ethz-b-000642285; http://hdl.handle.net/20.500.11850/642285

Process-based land surface models are important tools for estimating global wetland methane (CH₄) emissions and projecting their behavior across space and time. So far there are no performance assessments of model responses to drivers at multiple time scales. In this study, we apply wavelet analysis to identify the dominant time scales contributing to model uncertainty in the frequency domain. We evaluate seven wetland models at 23 eddy covariance tower sites. Our study first characterizes site-level patterns of freshwater wetland CH₄ fluxes (FCH₄) at different time scales. A Monte Carlo approach was developed to incorporate flux observation error to avoid misidentification of the time scales that dominate model error. Our results suggest that (a) significant model-observation disagreements are mainly at multi-day time scales (<15 days); (b) most of the models can capture the CH₄ variability at monthly and seasonal time scales (>32 days) for the boreal and Arctic tundra wetland sites but have ... : Journal of Geophysical Research: Biogeosciences, 128 (11) ...