We thank C. Jones, K. Tokarska, T. Mauritsen, A. Klein Tank, A. Gettelman, V. Eyring, C. Schleussner, J. Rogelj and J. Marotzke for discussions. Funding was provided by European Union’s Horizon 2020 Research and Innovation Programme under grant agreement no. 820829 (CONSTRAIN) and UKRI NERC grant NE/N006038/1 (SMURPHS). We acknowledge the World Climate Research Programme, which, through its Working Group on Coupled Modelling, coordinated and promoted CMIP6. We thank the climate modelling groups for producing and making available their model output, the Earth System Grid Federation (ESGF) for archiving the data and providing access, and the multiple funding agencies who support CMIP6 and ESGF. M. Schlund is thanked for providing CMIP ECS data.