BR received funding from a NOAA Climate Climate and Global Change Postdoctoral Fellowship, administered by the University Corporation for Atmospheric Research. DF acknowledges support of the Physical Oceanography program of NSF. We are grateful for helpful discussions with J. Marshall, D. Battisti, A. Czaja, C. Bitz, A. Donohoe, T. Schneider, P. O’Gorman, A. Plumb, D. Frierson and D. Schrag. We thank the editor Anthony Broccoli and three anonymous reviewers for helpful comments.
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This efficiency is weaker, for example, at higher planetary rotation rate (Vallis and Farneti 2009).
Differences between surface air temperature and SST are small, never exceeding 2°C in these simulations.
AHT is well approximated by the flux of moist static energy, defined as MSE = cpT + gz + Lq (notation standard), which can be further decomposed into dry static energy DSE = cpT + gz (the sum of internal and potential energy) and latent heat LH = Lq (Pierrehumbert 2010).
For N = 8 the anomaly from 2.5 PW to 4 PW OHT is shown instead, since in this case the model grows large sea ice caps with only 2 PW OHT.
To be clear, this mechanism is distinct from the dynamical ocean thermostat of Clement et al. (1996). They propose that the SST response to a zonally uniform sea surface heating from the atmosphere is damped by anomalous equatorial upwelling. We impose an oceanic heat sink at the equator (enhanced OHT) and find that the tropical SST response is damped by atmospheric processes.
A surface emissivity of εs = 0.98 is prescribed in our GCM.