Standard Presentation Australian Marine Sciences Association Annual Meeting 2023

Mean State And Intra-Annual Variability In Temperature Structure and Heat Transport In The East Australian Current System (#213)

Fernando Sobral 1 , Moninya Roughan 1 , Neil Malan 1 , Junde Li 1
  1. Coastal and Regional Oceanography Lab, School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW, Australia

Western boundary currents are important in redistributing heat from low to high latitudes. Previous studies of the East Australian Current (EAC) provided a general and limited (spatial and temporal) overview of the temperature variability and heat transport in the region. However, we are lacking a comprehensive systematic approach for the EAC System as a whole, characterising both the surface and subsurface variability and structure in temperature and ocean heat transport. Using a multidecadal ocean model we analysed and compared the monthly, seasonal and ocean mean state variability for the surface and sub-surface temperature and ocean heat transport structure. We found that the variability differs between the jet and eddy dominated regions. Also, the strongest net poleward heat transport (0.95 PW at 27°S), is found upstream of the region of maximum ocean heat content (0-2000m, centred at 32°S). Furthermore, net heat transport reduces south of this latitude by about 65%, in the eddy dominated zone. Understanding the ocean mean state and the intra-annual temperature and heat transport structure and variability gives us a baseline to assess long term trends related to climate change and to explore shorter time scale processes.