Long‐term trend and decadal variability of the southward penetration of the East Australian Current

Abstract

Observations from a long‐term ocean station off eastern Tasmania show that the southward penetration of the East Australian Current (EAC) has increased over the past 60 years. Changes in temperature and salinity are highly correlated at timescales greater than seasonal, with long‐term trends which differ markedly from global ocean values. The data show that the region has become both warmer and saltier with mean trends of 2.28°C/century and 0.34 psu/century over the 1944–2002 period which corresponds to a poleward advance of the EAC of ∼350‐km. These trends are not directly forced by global surface fluxes but primarily result from changes in the EAC. The summertime trends in temperature and salinity are greater than in winter – there is an augmented summer pulse of warm, high salinity subtropical water associated with the EAC.