A small Japanese boat confirmed to have been lost during the 2011 Japan tsunami has washed up on a remote Canadian island.
The green-and-white vessel was discovered by two locals on Spring Island, northwest of Vancouver Island. British Columbia's Emergency Management agency then matched the boat's serial number to one listed as lost by the Japanese consulate, according to the National Oceanic and Atmospheric Administration's (NOAA) Office of Response and Restoration.
The boat is not the first alien debris to wash up on the North American coast in the wake of the March 2011 tsunami. An estimated 5 million tons of debris were swept out to sea by the wave, and about 1.5 million tons of that is likely still in the Pacific Ocean, according to NASA estimates. There have been 11 confirmed tsunami debris sightings on the North American coast, according to NOAA, including a Harley-Davidson motorcycle found in Canada.
The most dramatic piece of debris to drift ashore so far is a 66-foot (20-meter)-long dock covered with an estimated 100 tons of urchins, starfish, crustaceans and other sea life. The dock beached in Oregon in June, triggering a massive clean-up effort in order to prevent invasive species on the dock from establishing themselves on the Oregon coast. [See Photos of the Japan Tsunami Debris]
NOAA expects that more debris will gradually come ashore over the next several years, but much of this debris will be indistinguishable from the usual flotsam and jetsam that washes up on beaches daily. The debris is highly unlikely to carry any radiation from the Fukushima nuclear plant disaster, experts say.
Researchers are working to map the path of tsunami debris as it spreads across the Pacific. Complicating the issue is that there is no single raft of trash — rather, the debris is spread out over miles.
"For me the story is not what's been found but what hasn't been found," NOAA oceanographer Glen Watabayashi said in a statement on NOAA's Office of Response and Restoration blog. "With all the summer vessel traffic along the West Coast and out in the North Pacific, there have been no reports of any large concentrations of debris."
Oceanographers like Watabayashi are using software designed to model the spread of oil during spills to pinpoint the current concentration of the debris. Summer weather and currents are keeping debris away from shore now, according to NOAA, though officials expect an uptick when wind patterns change in the fall.
Editor's note: This article has been updated to correct "U.S. coast" to "North American coast" in the third paragraph.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.