45) Where Will Debris from Japan's Tsunami Go?

 See Where Ocean Flows Are Carrying It

by Jaymi Heimbuch, San Francisco, California on 04. 8.11

        

This figure shows the probable pathways of the debris that entered the ocean on March 11, 2011, as estimated from historical trajectories of drifting buoys. View an animation. Credit: Nikolai Maximenko, International Pacific Research Center

The tsunami that hit Japan devastated buildings and farms, and carried entire houses down streets. But as waters retreated, tons of debris was washed into the sea. Where will all that garbage flow now that it has hit the open water? Researchers have created a guess at where and when we'll see refuse from the tsunami, including which shorelines will soon see debris from Japan's disaster washing up on beaches.

University of Hawaii at Manoa's Nikolai Maximenko and Jan Hafner have created a model for where debris will flow. It has been based on the movement of buoys deployed over the years for scientific research, and by watching how currents move the buoys, they are showing how objects from the tsunami will travel across the Pacific. 

The team estimates that the Northwestern Hawaiian Islands Marine National Monument will start to see trash within a year, and more trash will hit Hawaiian islands shores over the following year. 

Within three years, California will start to receive some of the garbage from the tsunami, and then much of the rest will be added to the GreatPacific Garbage Patch.

Finally, in five years, Hawaii will be hit again with a larger batch, and much of it will be stuck in amongst the coral reefs along its shores. 

Check out this amazing animation of how the debris moves from the shore of Japan, to the west coast of the US, and back to Hawaii. 

It sounds frustrating, especially knowing that any clean-up efforts will be difficult -- afterall, the Great Pacific Garbage patch and several other trash gyres around the world are nearly impossible clean-up tasks. While tracking debris from the tsunami will aid in scientific understanding about how materials flow, and change over time in the ocean, it doesn't exactly help us do the dirty work of cleaning up the mess. Still, knowing where and when the trash will hit can help with organizing shoreline cleanup efforts. 

Right now, TreeHugger Paula Alvarado is aboard the Sea Dragon with the 5 Gyres project. She's out with the research team tracking the extent to which marine litter is affecting the ocean. They're learning about the impacts of plastic pollution and, hopefully, what can be done about it.

Where will the debris from Japan's tsunami drift in the ocean?

The huge tsunami triggered by the 9.0 Tohoku Earthquake destroyed coastal towns near Sendai in Japan, washing such things as houses and cars into the ocean. Projections of where this debris might head have been made by Nikolai Maximenko and Jan Hafner at the International Pacific Research Center, University of Hawaii at Manoa. Maximenko has developed a model based on the behavior of drifting buoys deployed over years in the ocean for scientific purposes. 

The debris first spreads out eastward from the Japan Coast in the North Pacific Subtropical Gyre. In a year, the Northwestern Hawaiian Islands Marine National Monument will see pieces washing up on its shores; in two years, the remaining Hawaiian islands will see some effects; in three years, the plume will reach the US West Coast, dumping debris on Californian beaches and the beaches of British Columbia, Alaska, and Baja California. The debris will then drift into the famous North Pacific Garbage Patch, where it will wander around and break into smaller and smaller pieces. In five years, Hawaii shores can expect to see another barrage of debris that is stronger and longer-lasting than the first one. Much of the debris leaving the North Pacific Garbage Patch ends up on Hawaii's reefs and beaches. 

These model projections will help to guide clean-up and tracking operations. Tracking will be important in determining what happens to different materials in the tsunami debris, for example, how the composition of the debris plume changes with time, and how the winds and currents separate objects drifting at different speeds.

Even before the tsunami, the World Ocean was a dump for rubbish flowing in from rivers, washed off beaches, and jettisoned from oil and gas platforms and from fishing, tourist, and merchant vessels. Marine debris has become a serious problem for marine ecosystems, fisheries, and shipping. The presentations given at the recent week-long 5th International Marine Debris Conference in Hawaii, at which Maximenko had organized a day-long workshop, are a testimony to the magnitude of the ocean debris problem. The massive, concentrated debris launched by the devastating tsunami is now magnifying the hazards.

		IMAGE: The mass of debris stretches for miles off the Honshu coast.

Maximenko's long-standing work on ocean currents and transports predicted that there are five major regions in the World Ocean where debris collects if it is not washed up on shores or sinks to the ocean bottom, deteriorates, or is ingested by marine organisms. These regions turn out to be "garbage patches." The North Pacific Garbage Patch has become famous, the North Atlantic Patch was fixed some years ago, and the South Atlantic, South Indian Ocean, and South Pacific patches have just been found, guided by the map of his model that shows where floating marine debris should collect.