Articles | Volume 18, issue 1
https://doi.org/10.5194/os-18-1-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-18-1-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Review article
| 
04 Jan 2022
Review article |
| 04 Jan 2022
| 04 Jan 2022
Plastics in the Indian Ocean – sources, transport, distribution, and impacts
Charitha Pattiaratchi
CORRESPONDING AUTHOR
Oceans Graduate School and the UWA Oceans Institute, the University of Western Australia, Perth, 6009, Australia
Mirjam van der Mheen
Oceans Graduate School and the UWA Oceans Institute, the University of Western Australia, Perth, 6009, Australia
Cathleen Schlundt
GEOMAR, Helmholtz Centre for Ocean Research, Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
Bhavani E. Narayanaswamy
Scottish Association for Marine Science, Oban, Argyll, PA37 1QA,
Scotland, UK
Appalanaidu Sura
National Centre for Coastal Research, Ministry of Earth Sciences,
Chennai, 600100, India
Sara Hajbane
Oceans Graduate School and the UWA Oceans Institute, the University of Western Australia, Perth, 6009, Australia
Rachel White
School of Biological Sciences, the University of Western Australia,
Perth, 6009, Australia
Nimit Kumar
Ministry of Earth Sciences (MoES), Indian National Centre for Ocean
Information Services (INCOIS), Hyderabad, 500090, India
Michelle Fernandes
National Centre for Polar and Ocean Research, Ministry of Earth Sciences (MoES), Government of India, Headland Sada, Vasco da Gama 403 804, Goa, India
Sarath Wijeratne
Oceans Graduate School and the UWA Oceans Institute, the University of Western Australia, Perth, 6009, Australia
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Field measurements from different platforms that included satellite, ships, oceanographic moorings, highh frequency radar and ocean gliders were used to indentify petite-eddies (peddies) along the Western Australia. The flow features were mainly found in regions of high velocity shear along the periphery of larger eddies. The high Rossby numbers (>5) reflected the diminished effect of the earths rotation. The eddies controlled the advection and distribution of chlorophyll locally.
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Short summary
The Indian Ocean receives a large proportion of plastics, but very few studies have addressed the sources, transport pathways, and sinks. There is a scarcity of observational data for the Indian Ocean. Most plastic sources are derived from rivers, although the amount derived from fishing activity (ghost nets, discarded ropes) is unknown. The unique topographic features of the Indian Ocean that create the monsoons and reversing currents have a large influence on the transport and sinks.
The Indian Ocean receives a large proportion of plastics, but very few studies have addressed...
