Most of us probably remember the enormous earthquake that struck Japan a couple of years ago.  The earthquake and the tsunami it generated devastated Japan, causing $10 million dollars worth of damage and killing almost 230,000 people.  As if that was not enough, the earthquake and tsunami caused a meltdown at the Fukushima Nuclear Power Plant.   While I’m sure that all of us were horrified by the effect of the earthquake on Japan, it is easy to believe that destruction from the disaster was limited only to that region.  However, years later the effects of the earthquake are still being felt, mostly in the form of debris has been swept into the ocean.

Even before the earthquake there had been a problem with trash from Japan drifting across the Pacific towards the U.S. (and vice versa).  Trash can become caught in ocean currents like the Kuroshio Current carrying it away from Japan’s shores into the Pacific and possibly even to North America.

Some of the debris will end up trapped in one of infamous “Garbage Islands”, more formally known as the Great Pacific Garbage Patch.  The Garbage Patches (there are actually two, an east and a west) are located in the North Pacific Subtropical Gyre.  The Gyre is formed by four currents in the Pacific all moving in a clockwise direction.  The rotation of the gyre draws the trash into the calm stable center, where much of it becomes trapped.  Some of the debris escapes the gyre and is carried by ocean currents to the North American coastline.

No matter where marine debris ends up it is a danger to the wildlife.  Many animals mistake trash for food (for example loggerhead sea turtles often mistake plastic bags for jellyfish), which can create cause them to fall ill.  Marine mammals, such as seals, can become tangled in abandoned fishing nets.  The detritus can also block algae and plankton from receiving sunlight, causing the organisms to die off.  Such an event would be disastrous, as it would kill of organisms that depend autotrophs for food, creating a ripple effect throughout the food chain.  In addition to the normal dangers posed by marine debris, the tsunami brings specific problems as well.  In 2012, a dock from a Japanese shipyard washed up on an Oregon beach carrying dozens of species native to Japan, three of which were potentially invasive.  Oregon officials ended up blow torching the dock in order to prevent an outbreak of invasive species (species nonnative to an area that have the potential kill off indigenous species).

While marine detritus is a problem at the best of times, the tsunami only worsened an already bad situation.  The Japanese Government estimates that about 1.5 millions tons of garbage were generated by the tsunami, but it is difficult to pinpoint exactly what debris is from the tsunami, and what is just regular trash.  However, people been able to find at least some of the detritus from the tsunami.  Officials in Alaska have noticed a difference in the amount and type of trash along the state’s shores. While NOAA has found both possible and confirmed sightings of debris from the tsunami in both the North Pacific Subtropical Gyre and along the U.S. coastline.

Often when a natural disaster occurs it is easy to focus only the problems in that region.  And rightly so, after all it is the people and environment of that region that are most in need of aid.  Nevertheless, it is important to remember that the effects of events such as Japanese earthquake have a scope far beyond their origin.