Some Aspects of the Deep Circulation of the Tasman and Coral Seas

Abstract

Data from selected stations deeper than 2000 m in the Tasman and Coral Seas are used to prepare meridional sections of salinity, oxygen, and phosphate along the meridian 155º E. between latitudes 14º S. and 42º S., and zonal sections of the same properties between meridians 149º E. and 155º E. in the latitude range 14-15º S. Meridional changes in the salinity minimum, phosphate maximum, and deep salinity maximum indicate circulation below 1500 m. Utilizing all available data, the general circulation of these waters in the Tasman and Coral Seas as a whole is described. Phosphate-rich waters from the Equatorial Western Pacific and probably from the Indian Ocean are found distributed along the western margin to the north and south of the region, at about the 2000 m level. Below this level, well-oxygenated waters of high salinity, presumably from the South-West Pacific, enter the northern Tasman Sea, through the New Caledonian trench. By comparison of temperature, salinity, and oxygen values the depth of the sill connecting the Tasman and Coral Seas is estimated at 3000 m. Along the 155º E. meridian temperatures recorded during the late nineteenth century were warmer by 0. 15-0.3ºC than those obtained recently.