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Japan tracks tsunami debris as it spreads in Pacific

Tracking the debris from the Japan tsunami can be tricky, as it moves across the Pacific via ocean currents and winds. NBC's Miguel Almaguer reports.

TOKYO – On Thursday, the U.S. Coast Guard sank a wayward Japanese fishing vessel off the coast of Alaska that had floated across the Pacific after being ripped from its moorings by the huge tsunami that struck on March 11 last year.

But could more Japanese flotsam and jetsam reach U.S. shores?

Since last year, the Japanese government has been tracking and posting on a website detailed information of debris sightings collected from ships in the Pacific Ocean.

Reports of capsized boats peaked in July with 17 cases, dwindling to two found in November. There were no sightings for the months of December and January.

'Ghost ship' sinks to bottom of Gulf of Alaska after Coast Guard fires at it

According to the calculations by Japan's Cabinet Secretariat for Ocean Policy, as much as 5 million tons of debris, mostly damaged homes, were sucked into the sea by the tsunami. It is calculated that up to 70 percent of the material was concrete, which quickly sunk to the bottom of the ocean. But the remaining 30 percent may still be floating in the Pacific.

"Even though most nations have expressed their understanding that the debris was caused by an uncontrollable natural disaster, it nonetheless came from our country and we will do our utmost to fulfill our responsibilities" said Tetsuyuki Tamura, an official at the Ocean Policy department, adding that the most important task will be the sharing of information, particularly with the United States and Canada.

As for the effects of the meltdown at the Fukushima nuclear complex, the Japanese government said the risk of radiation in the ocean is low, citing the fact that most of the wreckage was pulled into the sea 24 hours before the troubles at the plant. As for any subsequent radiation particles washed into the sea, it would have been very little in relation to the huge amounts of water in the ocean.

Handout / Reuters

Japanese fishing vessel, "Ryou-Un Maru," shows significant signs of damage after U.S. Coast Guard Cutter Anancapa fired explosive ammunition into it, 180 miles west of the Southeast Alaskan coast on Thursday.

More photos of the 'ghost ship'

In February of this year, Japanese experts were dispatched to Hawaii to meet with their counterparts at the National Oceanic and Atmospheric Administration for further exchange of information.

As a result, sometime this month, Japan is expected to post a computer simulation of the debris traveling across the Pacific to help gauge its route and the speed. 

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