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There is a perception that no climate model has simulated the recent plateau of global warming that started around 2000. This warming slow-down is commonly referred to as the “early-2000s hiatus”. Though the multi-model ensemble average of uninitialized climate models indeed shows early-21st century warming greater than what has been observed, there are a number of individual ensemble members from several models that did actually simulate the early-2000s hiatus. Those simulations were successful because the internally generated naturally occurring climate variability associated with the negative phase of the Interdecadal Pacific Oscillation (IPO) happened, by chance, to coincide with the observed negative phase of the IPO that contributed to the early-2000s hiatus. However, picking out those skillful ensemble members in advance would not have been possible in the 1990s prior to the hiatus, and thus would have had no predictive value. If the recently developed methodology of initialized decadal climate prediction could have been applied in the 1990s, both the negative phase of the IPO in the early 2000s as well as the hiatus could have been predicted. The processes associated with this skillful prediction include more heat being mixed into the subsurface ocean as indicated by positive (downward) net surface heat flux over the global ocean, and stronger Pacific trade winds that intensify the Pacific Ocean subtropical cells and mix more heat into the subsurface ocean.
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