AGU: Geophysical Research Letters

 

Editors' Highlight

Stomatal conductance and climate sensitivity to carbon dioxide

In order to fix carbon, plants transpire water and take up atmospheric carbon dioxide (CO₂) through stomata, which are small openings in leaves that link the exchange of water and carbon of vegetated surfaces. The density of stomata on a leaf indicates the abundance of carbon dioxide in the atmosphere; high densities mean that CO₂ is scarce, while low densities mean that CO₂ is plentiful. This effect has previously been used to reconstruct CO₂ concentrations in the Earth's past. In the study by Kleidon (2007), this observed effect was reproduced with a coupled vegetation-climate model with the assumption that stomata function optimally to maximize growth. If such a shift is not assumed, climate model predictions of the expected rise in CO₂ will generally underestimate vegetative cover. Further, doubling the abundance of CO₂ in the atmosphere could increase land temperatures by 2.7°–3.2°C according to whether stomata adapt optimally or not at all.

View abstract

View full article (Subscription required)