December 12, 2013
NOAA and university scientists, using data from two ocean expeditions across the so-called Great Pacific Garbage Patch, found that tiny pieces of plastic (micro-plastic) were widespread, but the abundance and density varied both vertically in the water column and horizontally.
The expeditions crossed the North Pacific Subtropical Gyre, an ocean feature of rotating currents that traps material in the Garbage Patch.
"Knowing the size, abundance, distribution and movement of plastic particles in this area will build a foundation of information against which to measure change and a blueprint for collecting and sampling plastic particles for pollutants," said Michael Ford, a co-author of the study, and an Oceanographer in NOAA’s National Marine Fisheries Service.
In addition to Ford, authors included lead author Miriam Goldstein, Ph.D., who was at Scripps Institution of Oceanography, at the University of California, San Diego; and Andrew Titmus, who was at Hawai'i Pacific University.
The findings are here , in a study published November 20, 2013, in PLOS ONE, an international peer-reviewed online publication.
Plastic was collected using a special net, called a Manta net, that is designed to collect a continuous flow of plankton and flotsam. The net measures the volume of water passing through it as it collects tiny plastic samples in the fine mesh. These nets were towed from the side of NOAA Ship Okeanos Explorer during a 2010 expedition. The study also analyzes data and samples from the 2009 Scripps Accumulation of Plastic Expedition (SEAPLEX).
The authors also reported that plastic particles were distributed in patches and they observed more abundant plastic during the 2009 transit when lower winds were reported than during the 2010 transit that was marked by higher winds. The authors say that winds may have pushed plastic particles deeper into the water column where they were unseen until they later resurfaced, but emphasized that more study is needed.
NOAA Ship Okeanos Explorer explores the ocean for the purpose of discovery and the advancement of knowledge. NOAA's Office of Ocean Exploration and Research supported the 2010 mission, which is further described in NOAA News.
In addition to fostering partnerships between NOAA and universities, the 2010 NOAA expedition was a collaboration among four NOAA line offices. The Office of Ocean Exploration and Research in NOAA Research, conducted the exploration mission on NOAA Ship Okeanos Explorer, which is operated by NOAA's Office of Marine and Aviation Operations. The plastics data were collected through a partnership with NOAA Fisheries and will provide valuable information to the Marine Debris Program in NOAA's National Ocean Service.
"This cooperation helps provide baseline research to begin addressing the problem of the Pacific Garbage Patch and the effects of marine debris on marine life," said Robert S. Detrick, Ph.D., NOAA's assistant administrator for NOAA's Office of Oceanic and Atmospheric Research.
NOAA's Ocean Exploration Program is the only federal program dedicated to the systematic exploration of the planet's largely unknown ocean.
NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources.