Satellite observation of an annual cycle in the Agulhas Current

[1] Ocean models show an annual cycle in the Agulhas Current transport which has not yet been confirmed in analyses of in-situ or satellite observations. A cross-stream coordinate approach is used to study the variability of the Agulhas Current from 18 years of along-track altimetry and merged altimetry and close to 7 years of high frequency Sea Surface Temperature (SST) observations. While the position and width of the Agulhas Current’s dynamical core do not display an annual cycle, the geostrophic current speed at the current’s core exhibits distinct seasonal variations, with a stronger flow observed in austral summer. The annual cycle dominates the frequency spectra of the current’s core geo-strophic velocities. Citation: Krug, M., and J. Tournadre (2012), Satellite observations of an annual cycle in the Agulhas Current