The impact of cloud radiative feedback, remote ENSO forcing, and entrainment on the persistence of North Pacific sea surface temperature anomalies

Abstract The influence of cloud radiative feedback, remote ENSO heat flux forcing, and oceanic entrainment on persisting North Pacific sea surface temperature (SST) anomalies is investigated using a stochastically forced ocean mixed layer model. The stochastic heat flux is estimated from an atmospheric general circulation model, the seasonally varying radiative feedback parameter and remote ENSO forcing are obtained from observations, and entrainment is derived from the observed mean seasonal cycle of ocean mixed layer depth. Persistence is examined via SST autocorrelations in the western, central, and subtropical eastern North Pacific and for the leading pattern of variability across the basin. The contribution of clouds, ENSO, and entrainment to SST persistence is evaluated by comparing simulations with and without each term. The SST autocorrelation structure in the model closely resembles nature: the pattern correlation between the two is 0.87–0.9 in the three regions and for the basinwide analyses, an...