UH Mānoa scientist predicts plastic garbage patch in Atlantic Ocean

University of Hawaiʻi at Mānoa
Contact:
Tara Hicks Johnson, (808) 956-3151
Outreach Specialis, School of Ocean and Earth Science and Technology
Nikolai Maximenko, (808) 956-2584
Senior Researcher, International Pacific Research Center
Posted: Aug 19, 2010

Red in M's model shows biggest accumulation of drifters 10 years after uniform placement in ocean.
Red in M's model shows biggest accumulation of drifters 10 years after uniform placement in ocean.

Where does the plastic garbage in the ocean go? Twenty-two years worth of data collected by undergraduate students aboard a sailing vessel has identified widespread floating plastic debris in the western North Atlantic that is comparable to the ‘Great Pacific Garbage Patch.’ The study, led by a team of researchers from Sea Education Association (SEA), Woods Hole Oceanographic Institution (WHOI), and the University of Hawaiʻi at Mānoa, is published this week in Science Express.

UH Mānoa scientist Nikolai Maximenko, a co-author on the paper, has developed a computer model that describes how converging surface currents cause the plastic to accumulate in such garbage patches.

Students of the SEA collected samples of plastic in surface plankton nets at 6100 locations over the 22 years. The highest concentrations of plastic they found in a region of the North Atlantic predicted by Maximenko’s model, around 32°N (roughly the latitude of Atlanta, GA) and extending from 22-38°N latitude.

“The study is so exciting,” says Maximenko, oceanographer at the UH Mānoa International Pacific Research Center, “because it validates the computer model we’ve developed using more than 15,000 trajectories of drifting buoys. The purpose of the model is to track long-living objects that float on the ocean surface. Our model has already successfully reproduced the location of the ‘Great Pacific Garbage Patch.’ That now the debris in the North Atlantic collects mostly where our model predicts is further evidence that plastic moves in a similar way that drifters do. We can now expect that our model will be very useful in coordinating debris detection and clean up operations.”

The lead author of the paper, SEA scientist Kara Lavender Law, says "Not only does this important data set provide the first rigorous scientific estimate of the extent and amount of floating plastic at an ocean-basin scale, but the data also confirm that basic ocean physics explains why the plastic accumulates in this region so far from shore. 

Maximenko’s model predicts three other ocean “garbage patches” that have yet to be found: one in the South Atlantic, one in the South Pacific, and one in the South Indian Ocean. These patches are in regions that ships rarely visit. So here is an opportunity to discover yet another garbage patch, but you need a fine net as most of the plastic pieces in the present study and in the Great Pacific Garbage Patch are only millimeters in size.

For further information about Maximenko’s model, please see http://iprc.soest.hawaii.edu/newsletters/newsletter_sections/iprc_climate_vol8_2/tracking_ocean_debris.pdf.

This work was supported by the National Science Foundation and the Hollis and Ermine Lovell Charitable Foundation. NM and JH were supported by the National Fish and Wildlife Foundation, NASA, NOAA and the Japan Agency for Marine-Earth Science. 

Paper Information: Kara Lavender Law, Skye Morét-Ferguson, Nikolai A. Maximenko, Giora Proskurowski, Emily E. Peacock, Jan Hafner, and Christopher M. Reddy: Plastic accumulation in the North Atlantic subtropical gyre, Published Online August 19, 2010, Science DOI: 10.1126/science.1192321.

Researcher Contact: Senior Researcher Nikolai A. Maximenko, International Pacific Research Center, School of Ocean and Earth Science and Technology, University of Hawaiʻi at Mānoa, (808) 956-2584; maximenk@hawaii.edu
 
International Pacific Research Center Media Contact: Gisela Speidel (808) 956-9252; gspeidel@hawaii.edu
 
The International Pacific Research Center (IPRC) of the School of Ocean and Earth Science and Technology (SOEST) at theUniversity of Hawaiʻi at Mānoa is a climate research center founded to gain greater understanding of the climate system and the nature and causes of climate variation in the Asia-Pacific region and how global climate changes may affect the region. Established under the “U.S.–Japan Common Agenda for Cooperation in Global Perspective” in October 1997, the IPRC is an international collaboration supported by agencies in Japan and the United States and by the University of Hawaiʻi.