Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

What has happened to the tsunami debris from Japan?

21.02.2014
Outcomes from synthesis of model and observations

The amount of debris in the ocean is growing exponentially, becoming more and more hazardous and harmful to marine life and therefore also to our ocean food source. Measuring and tracking the movements of such debris are still in their infancy. The driftage generated by the tragic 2011 tsunami in Japan gave scientists Nikolai Maximenko and Jan Hafner a unique chance to learn about the effects of the ocean and wind on floating materials as they move across the North Pacific Ocean.


This is an image of location of different types of tsunami driftage on Feb. 20, 2014. Orange regions show where items of high boyancy, or high windage, may be found. Dark blue to purple show regions where objects of low windage, lying low in the water may be found. The animation is at http://iprc.soest.hawaii.edu/users/hafner/PUBLIC/
TSUNAMI_DEBRIS/WINDAGE_03/ANIMATION_1/
movie_windages.gif.

Credit: Nikolai Maximenko and Jan Hafner, International Pacific Research Center, University of Hawaii

Shortly after the tsunami struck, Maximenko and Hafner used the IPRC Ocean Drift Model to predict where the debris from the tsunami would go. Their computer model is based on trajectories of real satellite-tracked drifting buoys and satellite-measured winds.

The model has now been charting the possible paths of the tsunami driftage for nearly 3 years. The scientists have made a major improvement to the initial model: it now accommodates objects of different shapes and buoyancies that expose different amounts of surface to the wind and travel at different speeds and different trajectories. The model therefore now includes different levels of wind-forcing, simulating the movement of different types of floating debris.

No formal marine debris observing systems exist to verify the model simulations. The model paths for tsunami debris, however, agree with reports of such debris washing up on the shores of Oregon, Washington, Alaska, and the Hawaiian Islands, as well as with observations by sailors crossing the North Pacific.

The first physical evidence of tsunami driftage far from the coasts of Japan, for example, came in September 2011 from the Russian sail training ship Pallada. The captain had been forewarned that the ship might run into a tsunami debris field on its voyage from Honolulu to Vladivostok. Sailors, alerted and on the lookout, sighted much debris just northwest of Midway, and picked up a little fishing boat later confirmed lost in the tsunami.

The model predicted both the timing and the type of material that has washed up along windward shores of Hawaii: the first tsunami driftage came in August – September 2012, about 1½ years after the tragedy. These were very buoyant pieces, for example, oyster buoys, crates, small fishing boats like the one picked up by Pallada, and parts of small refrigerators.

Then 2½ years after the tsunami, materials sitting lower in the water and less buoyant than the previous driftage arrived: poles and beams with mortise and tenon features. Experts on lumber, who have analyzed cross-cuts of several of these wood pieces, agree that it is Sugi, a species of cypress endemic to Japan. One piece of wood is of very old timber and must have been cut 100 or more years ago.

The IPRC Ocean Drift Model has recently shown to be useful in another dramatic event at sea: validating the El Salvadoran castaway's ordeal. In January 2014, Jose Salvador Alvarenga washed ashore in the Marshall Islands after enduring a 13-month journey from the shores of southern Mexico. The paths of floating objects in the IPRC Ocean Drift model, driven with the currents and wind conditions, lend strong support to this rather improbable odyssey. Details are at http://iprc.soest.hawaii.edu/news/marine_and_tsunami_debris/2014/14_02_Maximenko_fisherman.pdf.

Hafner, J.; Maximenko, N.; STORY OF MARINE DEBRIS FROM THE 2011 TSUNAMI IN JAPAN IN MODEL SIMULATIONS AND OBSERVATIONAL REPORTS
(Abstract ID: 13323)
Oral presentation
Session #:140
Date: 2/24/2014
Time: 08:00
Location: 316 B
http://www.sgmeet.com/osm2014/viewabstract.asp?AbstractID=13323
Scientist Contacts
Jan Hafner - email: jhafner@hawaii.edu
Nikolai Maximenko – email: maximenk@hawaii.edu
Outreach
Gisela Speidel, International Pacific Research Center Outreach – email: gspeidel@hawaii.edu

Gisela Speidel | EurekAlert!
Further information:
http://www.hawaii.edu

More articles from Earth Sciences:

nachricht Radioactivity from oil and gas wastewater persists in Pennsylvania stream sediments
22.01.2018 | Duke University

nachricht World’s oldest known oxygen oasis discovered
18.01.2018 | Eberhard Karls Universität Tübingen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Thanks for the memory: NIST takes a deep look at memristors

22.01.2018 | Materials Sciences

Radioactivity from oil and gas wastewater persists in Pennsylvania stream sediments

22.01.2018 | Earth Sciences

Saarland University bioinformaticians compute gene sequences inherited from each parent

22.01.2018 | Life Sciences

VideoLinks Wissenschaft & Forschung
Overview of more VideoLinks >>>