Why do models disagree on temperature variability?
Climate models have problems. The problems are as old as science attempts to understand climate change by model simulation. That will last until a thorough ocean observation system is in place, and overriding impact of the oceans on climate is accepted, understood and applied in climate sciences..
Since it is known that unforced GMST (‘global mean surface temperature’ ) variability is heavily influenced by tropical Pacific surface temperatures, it might be tempting to suppose that the large inter-model spread in the simulated magnitude of GMST variability is due to model disagreement in the amount of simulated tropical Pacific variability. Perhaps surprisingly, our study shows that this is not the case and that the spread in the magnitude of model-simulated GMST variability is linked much more strongly to model disagreements over high-latitude oceans. Our findings suggesting that improving the simulation of air-sea interaction in these high-latitude ocean regions could narrow the range of simulated GMST variability, advance our fundamental understanding of natural variability, and appreciably improve our ability to forecast global warming on policy-relevant timescales.
With this understanding science is unlikely to make any progress, as the analysis ignores completely the changing of internal oceanic forces, with a physical capacity 1’000 times higher as of the atmosphere. However it is to acknowledge that Dr. Brown realizes that further progress is not possible without more attention to the sea.