Science Meetings

Impact of Satellite SSS on ENSO Forecasts for the Tropical Into-Pacific (Poster)
Hackert, E.C., and Busalacchi, A.J. (04-Dec-12)

In earlier work we have demonstrated that assimilation of gridded fields of sea surface salinity (SSS), derived from in situ salinity observations, has led to significantly improved coupled forecasts for lead times greater than 6 months (Hackert et al., 2011). We found that the positive impact of SSS assimilation is brought about by surface freshening in the western Pacific that led to increased barrier layer thickness (BLT) and shallower mixed layer depth. Thus, the net effect of assimilating SSS is to increase stability, reduce mixing, and shoal the thermocline which amplifies the wind component of ENSO coupling. Here we test the impact of Aquarius and SMOS SSS assimilation by comparing coupled experiments initiated from satellite versus in situ SSS assimilation and run for 12 months for each month August 2011 to July 2012. Although there is not enough data to rigorously validate any conclusions, we show preliminary results highlighting the potential positive impact of satellite SSS assimilation on ENSO forecasts.