The Patch is characterized by exceptionally high concentrations of pelagic plastics, chemical sludge, and other debris that have been trapped by the currents of the North Pacific Gyre. Despite its size and density, the patch is not visible from satellite photography since it primarily consists of suspended particulates in the upper water column. Since plastics break down to ever smaller polymers, concentrations of submerged particles are not visible from space, nor do they appear as a continuous debris field. Instead, the patch is defined as an area in which the mass of plastic debris in the upper water column is significantly higher than average.
Monday, January 23, 2012
The Great Pacific Garbage Patch, also described as the Pacific Trash Vortex, is a gyre of marine litter in the central North Pacific Ocean located roughly between 135° to 155°W and 35°N to 42°N. The patch extends over an indeterminate area, with estimates ranging very widely depending on the degree of plastic concentration used to define the affected area. Although many media and advocacy reports have suggested the patch extends over an area larger than the continental U.S, recent research sponsored by the National Science Foundation suggests the affected area may be twice the size of Texas, while a recent study concluded that the patch might be even smaller. This can be attributed to the fact that there is no specific standard for determining the boundary between the “normal” and “elevated” levels of pollutants and what constitutes being part of the patch. The size is determined by a higher-than normal degree of concentration of pelagic debris in the water. Recent data collected from Pacific albatross populations suggest there may be two distinct zones of concentrated debris in the Pacific.