Seasonal dependence of the WES feedback in the Pacific

An important element of meridional variability in the tropics is a feedback between the tropical winds, evaporation, and sea surface temperature (the so-called WES feedback). We use the NCAR Community Atmospheric Model to investigate the seasonal dependence of the WES feedback in the Pacific. Results indicate that the seasonal cycle of winds in the near-equatorial tropical Pacific have a strong influence on the strength of the WES feedback, and may even change the sign of the feedback during boreal summer. The importance of the WES feedback in affecting ENSO variability is also discussed.