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Title: Dynamics of ENSO Phase–Locking and Its Biases in Climate Models
Abstract The contributions of different oceanic feedbacks to the El Niño–Southern Oscillation (ENSO) phase‐locking are examined by deriving ENSO dynamics based on the recharge‐discharge framework. In observations, the significant winter preference of the ENSO peak is determined by a strong seasonal modulation of SST growth rate, which is controlled by the zonal advective and thermodynamic feedbacks. However, the majority of climate models fail to simulate ENSO phase‐locking because the contribution of zonal advective feedback to the seasonal modulation of the SST growth rate is much smaller compared to observations. The weak annual cycle of the SST‐current coupling coefficient and small annual mean of the negative climatological zonal SST gradient are two factors contributing to the weak‐biased seasonality of zonal advective feedback. Further analysis shows that the Niño3.4 SSTA has better phase‐locking performance than Niño3 SSTA in the climate models due to the better simulation of zonal advection feedback in the Niño3.4 region.  more » « less
Award ID(s):
1813611
PAR ID:
10367555
Author(s) / Creator(s):
 ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
49
Issue:
3
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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