Science Meetings

Space and Time Scales of Sea Surface Salinity and Freshwater Forcing Variability in the Global Ocean (60°S-60°N)
Bingham, F. and Lee, T. (16-Dec-16)

Using Aquarius Version-4 data, we have investigated the time and space scales of sea surface salinity (SSS) over the global ocean between 60°S and 60°N. Decorrelation time scales of SSS were found to be divided among less than 80 days (covering 1/2 of ocean area), 80-100 days (1/3) and greater than 100 days (remainder). Once the seasonal cycle is removed, shorter time scales (less than 80 days) dominate. Spatial scales are largest in the tropics along the intertropical convergence zones of all oceans and the South Pacific convergence zone in the South Pacific. Time scales were also calculated for time-integrated cumulative surface freshwater forcing (CFWF) using precipitation from Tropical Rainfall Measurement Mission and evaporation from OAFlux data. These showed little spatial pattern, but a dominance of the seasonal and longer time scales over the globe. The lack of correspondence between dominant temporal and spatial scales of SSS and CFWF highlights the importance of ocean processes in regulating SSS variability.