Deep dive to save the ocean
Eight million tonnes of plastic go into the sea every year and by 2050 it is estimated that there will be as much plastic as there are fish in our oceans. The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has joined in the global research effort to investigate marine plastic pollution, particularly in the area of microplastic: tiny particles from products such as toothpaste and cosmetics or ground down from larger plastic debris. “Microplastic is everywhere: the Arctic, Antarctic, even Point Nemo - the most remote point in the ocean,” says Sanae Chiba (lower left), leader of JAMSTEC’s marine plastic research group.
As plastics float in the water, ocean currents bring them together in enormous accumulations; one of these clusters, the western North Pacific Garbage Patch, lies south of Japan. JAMSTEC is targeting new research efforts here since it has been studied little so far. The agency is well known for its deep-sea research and recently made public a 30-year data set revealing that plastics were already in the sea in the 1980s. Chiba’s new team - formed in 2019 - aims to make a fresh contribution to the work already being done on marine plastic by other institutions. “Our focus is to fill the knowledge gap: one area is deep-sea research; another is microplastics that are smaller than 300 micrometres”. Often missed by regular sample collection, they are small enough to enter the food chain from plankton before working their way to humans; the toxic chemicals attached to plastics are also harmful. Scientists urgently need more data to see the overall picture. Conventional methods of microplastic analysis, where every piece is identified under a microscope, are time-consuming so JAMSTEC is also working on innovations to speed up data production and improve accuracy.
Ultimately this is a collective effort involving scientists from all over the world. “Marine plastic pollution is a transborder problem,” says Chiba.
At the 2019 G20 summit in Osaka, Japan, world leaders agreed the Osaka Blue Ocean Vision, which aims to reduce new marine plastic pollution to zero by 2050. Japan also launched its own initiative to help developing countries recover ocean litter and build more effective waste-management systems.
Awareness of marine plastic pollution is growing, as is the need for international partnerships to tackle it, such as the Osaka Blue Ocean Vision. While leaders at the G20 summit there agreed to take bold action to reduce marine plastics, they also stressed the need for evidence-based approaches and scientific co-operation. Data-sharing by research institutions and contributions from non-scientific ships such as pleasure boats, ferries and cargo vessels are all part of increasing the understanding of our oceans. Education and outreach play an important role too.
JAMSTEC scientists, led by Chiba, participated in the 2019-2020 Japan to Palau Goodwill Yacht Race. The race had two goals: marine plastic pollution research and educating the next generation. One of the racing yachts, Trekkee, collected data (showing how the sailing community can make its contribution), while an education programme for children from Palau taught conservation on board the sail training vessel, Miraie, a tall ship built in 1993. Another plus for the future of science in Japan was the research team on the Miraie: three women, rare in a field that has seen an uneven gender balance. Sadly they found microplastics even in Palau’s seemingly pristine waters. Marine pollution, overfishing and climate change are challenges facing this small Micronesian country.