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Investigating the Pathways of Marine Debris Found in the Arafura and Timor Seas David Griffin, CAWCR Ilse Kiessling, DEWHA 29 July 2008
Investigating the Pathways of Marine Debris Found in the Arafura and Timor Seas
David Griffin, CAWCR
Ilse Kiessling, DEWHA
29 July 2008
Pathways of Marine Debris
Marine debris – not easy to clean up
Pathways of Marine Debris
Many thousands of tonnes of nets
Pathways of Marine Debris
not just ugly
Pathways of Marine Debris
Pathways of Marine Debris
high concentrations: northern Gulf of Carpentaria
Pathways of Marine Debris
White (2004) hypothesis
Pathways of Marine Debris
Bluelink Reanalysis: 0-10m, daily velocity average,release items for 1 year, follow them for another year
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Add wind*3% to 0-10m, daily average current
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Feb0-10m
Pathways of Marine Debris
May0-10m
Pathways of Marine Debris
Aug0-10m
Pathways of Marine Debris
Nov0-10m
Pathways of Marine Debris
Pathways of Marine Debris
Pathways of Marine Debris
Conclusions
• Do nets move at the 0-10m velocity?• If so, the model suggests they must come from the Pacific.• But few nets are found on the Great Barrier Reef• probable explanation:• the model has too much flow through Torres
Pathways of Marine Debris
Recommended future work
• include effect of tides on bottom drag• determine drift characteristics of derelict nets• validate model by releasing drifters in Arafura Sea
