Moving beyond the incorrect but useful paradigm: reevaluating big-leaf and multilayer plant canopies to model biosphere-atmosphere fluxes – a review

The land surface models that provide fluxes of energy and mass to the atmosphere in weather forecast climate typically represent plant canopies as a homogenous single layer phytomass without vertical structure (commonly referred big leaf). This modeling paradigm harkens back 30–40-year-old debate about whether big-leaf adequately simulate for vegetated surfaces compared more complex computationally costly multilayer canopy models. article revisits scientific debate. We review early literature place our findings context discuss recent advancements roughness sublayer theory, observations leaf traits, computational methods facilitate use Using model with variable resolution, we compare representation equivalent one-layer ask how well replicates benchmark identify why differences occur. Comparisons flux tower measurements at several forest sites spanning multiple years show sensible heat flux, latent gross primary production, friction velocity degrade comparison canopy. For considered, 5–10 layers sufficiently reproduce observed fluxes. Vertical variation within-canopy air temperature, specific humidity, wind speed alters profile water potential, which upper is water-stressed on dry soils, also causes between canopies. suggest community should revisit parameterizations used