EnsoFbSstTaux
SST-Taux_feedback: coupling between SST anomalies in the eastern equatorial Pacific and Taux anomalies in the western equatorial Pacific
Computes zonal wind stress anomalies (TauxA) in the western equatorial Pacific (horizontal Niño4 average) regressed onto sea surface temperature anomalies (SSTA) in the eastern equatorial Pacific (horizontal Niño3 average).
TropFlux 1979-2018 (main)
SST: ERSSTv5 1854-2023, HadISST 1870-2023, COBE2 1850-2023, ERA5 1940-2022, 20CRv3 1836-2015, NCEP2 1979-2023
Taux: ERA5 1940-2022, 20CRv3 1836-2015, NCEP2 1979-2023
Niño3, Niño4
None
- seasonal cycle removed
- detrending (if applicable)
- spatial average
- seasonal cycle removed
- detrending (if applicable)
- spatial average
- TauxA regressed onto SSTA (slope)
- abs((model-ref)/ref)*100
monthly
% of error
- sea surface temperature (SST)
- zonal wind stress (Taux)
The first level shows the diagnostic used to compute the metric and highlight the difference between the model and the reference.
Figure 1: scatterplot of sea surface temperature anomalies (SSTA) in the eastern equatorial Pacific (Niño3 averaged) and zonal wind stress anomalies (TauxA) in the western equatorial Pacific (Niño4 averaged), showing the strength of the SST-to-Taux coupling (usually too weak). The black and blue markers show respectively the reference and the model. The metric is based on the slope of the regression and is the absolute value of the relative difference: abs((model-ref)/ref)*100.
The second level tests the hypothesis of a nonlinear relationship between SSTA<0 and SSTA>0.
Figure 2: scatterplot of sea surface temperature anomalies (SSTA) in the eastern equatorial Pacific (Niño3 averaged) and zonal wind stress anomalies (TauxA) in the western equatorial Pacific (Niño4 averaged), showing the possible nonlinearity in the strength of the SST-to-Taux coupling (usually shows no nonlinearity in both reference and model). The black, red and blue lines and numbers show respectively linear regression computed for all SSTA, SSTA>0 and SSTA<0, the left and right scatterplots show respectively the reference and the model.
The third level shows the remote coupling in the equatorial Pacific.
Figure 3: spatial structure of zonal wind stress anomalies (TauxA) in the equatorial Pacific (meridional 5°S-5°N average; zonal 30° running average) regressed onto sea surface temperature anomalies (SSTA) in the eastern equatorial Pacific (Niño3 averaged), showing the possible nonlinearity in the strength of the SST-to-Taux coupling (the reference shows the maximum coupling around the dateline, west of the dateline for SSTA<0, east of the dateline for SSTA>0, but the amplitude of the maximum coupling is about the same; usually the models do not reproduce the displacement of the maximum coupling for all SSTA, SSTA<0, SSTA>0 and simulate a weakening of the coupling for SSTA<0). The black, red and blue lines and numbers show respectively linear regression computed for all SSTA, SSTA>0 and SSTA<0, the dashed and solid curves show respectively the reference and the model.
The fourth level shows the spatio-mean annual structure of the coupling.
Figure 4: spatio-mean annual structure of zonal wind stress anomalies (TauxA) in the equatorial Pacific (meridional 5°S-5°N average; zonal 30° running average) regressed onto sea surface temperature anomalies (SSTA) in the eastern equatorial Pacific (Niño3 averaged), showing the possible nonlinearity in the strength of the SST-to-Taux coupling (usually shows too weak, particularly during boreal autumn and winter coupling, the reference indicates that the coupling stops in boreal spring when SSTA<0 but not when SSTA>0, while the models usually simulate a stop of the coupling in both case). The first, second and third rows show respectively linear regression computed for all SSTA, SSTA>0 and SSTA<0, the left and right Hovmöllers show respectively the reference and the model.