title: Impact of the representation of stomatal conductance on model projections of heatwave intensity.
abstract: Stomatal conductance links plant water use and carbon uptake, and is a critical process for the land surface component of climate models. However, stomatal conductance schemes commonly assume that all vegetation with the same photosynthetic pathway use identical plant water use strategies whereas observations indicate otherwise. Here, we implement a new stomatal scheme derived from optimal stomatal theory and constrained by a recent global synthesis of stomatal conductance measurements from 314 species, across 56 field sites. Using this new stomatal scheme, within a global climate model, subtantially increases the intensity of future heatwaves across Northern Eurasia. This indicates that our climate model has previously been under-predicting heatwave intensity. Our results have widespread implications for other climate models, many of which do not account for differences in stomatal water-use across different plant functional types, and hence, are also likely under projecting heatwave intensity in the future.
authors.affiliation: School of Veterinary and Life Sciences - Environmental and Conservation Sciences, Murdoch University, Perth, Western Australia, Australia.|Australian Research Council Centre of Excellence for Climate Systems Science and Climate Change Research Center, University Of New South Wales, New South Wales, Australia.
authors.forename: Jatin
authors.initials: J
authors.lastname: Kala
authors.affiliation: Macquarie University, Department of Biological Sciences, Sydney, Australia.
authors.forename: Martin G
authors.initials: MG
authors.lastname: De Kauwe
authors.affiliation: Australian Research Council Centre of Excellence for Climate Systems Science and Climate Change Research Center, University Of New South Wales, New South Wales, Australia.
authors.forename: Andy J
authors.initials: AJ
authors.lastname: Pitman
authors.affiliation: Hawkesbury Institute for the Environment, University of Western Sydney, Sydney, Australia.
authors.forename: Belinda E
authors.initials: BE
authors.lastname: Medlyn
authors.affiliation: Commonwealth Scientific and Industrial Research Organisation, Ocean and Atmosphere Flagship, Aspendale, Victoria, Australia.
authors.forename: Ying-Ping
authors.initials: YP
authors.lastname: Wang
authors.affiliation: Australian Research Council Centre of Excellence for Climate Systems Science and Climate Change Research Center, University Of New South Wales, New South Wales, Australia.
authors.forename: Ruth
authors.initials: R
authors.lastname: Lorenz
authors.affiliation: Australian Research Council Centre of Excellence for Climate Systems Science and Climate Change Research Center, University Of New South Wales, New South Wales, Australia.
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Perkins-Kirkpatrick