The physical setting

The summer and winter temperatures, phosphates, dynamic heights and water masses,of Tasmanian surface waters have been charted. Differences in the characteristics of coastal and offshore waters and of the contribution of upwelling, convective overturn and cyclonic eddies to the surface phosphate concentrations are examined. It is concluded that limited entry of surface sub-Antarctic waters, in combination with a prevalence ot sub-tropical waters, maintains nutrient concentrations in Tasmanian surface waters at levels only marginally richer than Australian ocean waters in general.