Climate impact of stratospheric ozone recovery

Slimane Bekki (1) , Alexandru Rap (2) , Virginie Poulain (1) , Sandip Dhomse (2) , Marion Marchand (1) , Franck Lefèvre (1) , Piers M. Forster (2) , Sophie Laval-Szopa (3, 4) , Martyn P. Chipperfield (2)

1 STRATO - LATMOS
2 ICAS - Institute for Climate and Atmospheric Science [Leeds]
3 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
4 CLIM - Modélisation du climat

Past stratospheric ozone depletion has acted to cool the Earth's surface. As the result of the phase-out of anthropogenic halogenated compounds emissions, stratospheric ozone is projected to recover and its radiative forcing (RF-O₃ ~ -0.05 W/m² presently) might therefore be expected to decay in line with ozone recovery itself. Using results from chemistry-climate models, we find that, although model projections using a standard greenhouse gas scenario broadly agree on the future evolution of global ozone, they strongly disagree on RF-O₃ because of a large model spread in ozone changes in a narrow (several km thick) layer, in the northern lowermost stratosphere. Clearly, future changes in global stratospheric ozone cannot be considered an indicator of its overall RF. The multi-model mean RF-O₃ estimate for 2100 is +0.06 W/m² but with a range such that it could remain negative throughout this century or change sign and reach up to ~0.25 W/m².

Mots clés: Stratospheric ozone; Climate

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]; Climatologie; Milieux et Changements globaux

Slimane Bekki, Alexandru Rap, Virginie Poulain, Sandip Dhomse, Marion Marchand, et al.. Climate impact of stratospheric ozone recovery. Geophysical Research Letters, 2013, 40 (11), pp.2796-2800. ⟨10.1002/grl.50358⟩. ⟨hal-00802252⟩