The Role of Salinity in Pacific Surface Height Variability and in Diagnosing 
the Hydrological Cycle

Elizabeth Douglass, Dean Roemmich, John Gilson, Detlef Stammer
Scripps Institution of Oceanography, La Jolla CA 92093-0230 USA


We present a preliminary analysis of Argo data, XCTD profiles, and results from 
the ECCO assimilation project with respect to the role of salinity in the variability 
of seasurface height and the use of salinity measurements to improve our understan
ding of the hydrological cycle in the ocean. 

The Argo Project  part of the legacy of WOCE - marks the first globally repeating 
measurements of subsurface salinity, with the data freely available in near real-time. 
A sparse but rapidly growing Argo array is now operating in the tropical Pacific, 
returning temperature and salinity profiles every 10 days from 1000 m to the sea surface. 
These data, plus XCTD profiles from several High Resolution XBT/XCTD lines, are used to 
assess the quality of results from data assimilation activities in the Pacific Ocean. 
A synthesis of the data and a model will then be used to understand the magnitude of 
salinity variability and its contribution to density and sea surface height. They are 
also used for diagnosing precipitation minus evaporation (P-E) anomalies, both locally 
in surface waters, and remotely in subducted water masses. Substantial interannual signals 
in salinity occur in the upper Pacific Ocean, whose understanding will help to unravel 
the puzzle of ENSO and other modes of cl imate variabilty.