Five years ago, a 30 foot wall of cold, black water crashed into the east coast of Japan. The tsunami's raging waters, which were triggered by a 9.0 earthquake, killed nearly 16,000 people, wiped out entire towns and villages and caused one of the world's worst nuclear disasters.
The power of the tsunami was so strong that the debris washed into the ocean included fishing boats, entire houses, cars and everything in between, totaling more than one million tonnes of wreckage.
Within days of the Great East Japan Earthquake, the patches of disaster debris floating off Japan's coast were so large that they were visible on satellite images.
Swept along by large circular currents and winds, the floating debris has since crossed the Pacific Ocean, hitting coastlines in America and Canada - everything from refrigerators to sports balls. Much of the debris has gathered in floating islands of waste 25 kilometres offshore, waiting for a storm surge to wash the debris ashore.
As the world commemorates the fifth anniversary of the earthquake, the tsunami and the resulting Fukushima nuclear disaster, the journey taken by the debris from the tragedy underscores the immense environmental problem that marine waste and litter poses.
The floating islands of debris, which have crossed the Pacific Ocean, also highlight the importance of transboundary, global collaboration in preventing and reducing the harmful impact of marine litter. In a sign of cooperation between governments, Japan gave the United States $3 million towards cleaning up the tsunami debris that washed ashore on its coastlines.
Marine litter that comes from land-based as well as sea-based sources can harm ecosystems, human health and economies. Debris can entangle sea animals while plastic micro-particles can accumulate in plankton. Albatrosses that feed on surface floating food such as squid and shrimps cannot distinguish between the food and the floating plastic debris, which they then feed to their chicks.
Ghost fishing is also a major problem. Nets lost at sea continue to drift and catch fish, which then die and decompose. The nets continue to catch more fish in a potentially endless cycle that kills off vast amounts of marine resources and harms fisheries.
The distance litter can travel - from one country to another, across oceans and seas - and the scale of the problem makes marine debris a global concern that requires countries to work together. The issue is too big for any one country, organization or agency to address alone.
Hosted by the United Nations Environment Programme (UNEP), the Global Partnership on Marine Litter brings together inter-governmental agencies, civil society, governments, the private sector and academia to prevent and reduce the impact of marine litter.
The urgency of addressing marine litter was recognized in 2014 at the First UN Environment Assembly (UNEA-1), the highest-level decision-making body on the environment. The marine litter resolution that passed at UNEA-1 asked UNEP to undertake a study on marine plastic debris and microplastics and to come up with urgent action plans on how to tackle the problem.
The study will be released ahead of the next meeting of UNEA, which takes place in Nairobi in May. It will be used to inform the Assembly's debate about how the world should respond to the problem.
"Marine litter is a major concern that requires the world to act together to address its harmful impacts on our oceans," said UNEP's executive director, Achim Steiner. "The upcoming United Nations Environment Assembly offers an opportunity for countries of the world to come up with an action plan on marine litter that will benefit both human lives and those of ocean wildlife."
