Map: Upwelling in the Australian region

Brief description

This map was produced from a hand drawn map showing upwelling around Australia. The hand drawn map is a qualitative summary of published information on upwelling. Upwelling around Australia tends to be intermittent and localised, and thereby make only a relatively modest contribution to total primary production. A range of processes are responsible for the upwelling that does occur. In a system with classical wind-driven upwelling, surface waters are pushed away from the coast by wind-stress to be replaced by cold nutrient-rich waters from the deeper shelf. Such events have usually been observed in summer off southwestern Australia and in parts of the Great Australian Bight when winds are favorable to upwelling. On the NSW coast, significant upwelling only occurs when northerly winds and encroaching eddies from the East Australia Current combine to bring water from the outer-shelf and upper-slope into the surface waters of the inner shelf. A third mechanism applies to some tropical waters, where tidal motions over the steep upper slope generate large internal waves that subsequently break and mix deeper nutrient-rich waters up into the surface layer. This map has been produced by CSIRO for the National Oceans Office, as part of an ongoing commitment to natural resource planning and management through the 'National Marine Bioregionalisation' project. Data depicted is a qualitative summary of published information. Variations in onscreen colour representation or printed reproduction may affect perception of the contained data.

Lineage

Progress Code: completed

Maintenance and Update Frequency: notPlanned

Statement: Map was from hand drawn map supplied by Madeleine Cahill and Scott Condie of CSIRO. Data depicted on map from various published information and experience of scientists. The map layers and design layout were assembled using ESRI ArcGIS products by Donna Hayes at CSIRO. Grids used for mapping were spline interpolated from the 1/2 degree grids.