Rapid thermal equilibration under piControl forcing in a mesoscale dominant climate model

We consider a new hierarchy of eddying climate models from GFDL using the MOM6 ocean code. A particularly remarkable characteristic of the finest resolution model (1/8th degree ocean) is that it thermally equilibrates in a pre-industrial control simulation within 100 years, rather than the usual 1000+ years. We hypothesize that this short equilibration time arises from two features of the ocean model: low spurious mixing from numerical advection, and strong mesoscale eddy transport. If supported by other models, this result suggests that eddying climate simulations are about an order of magnitude less expensive (in energy and time) than previously assumed.