Great Pacific garbage patch

The Great Pacific garbage patch, also described as the Pacific trash vortex, is a gyre of marine debris particles in the central North Pacific Ocean discovered between 1985 and 1988. It is located roughly between 135°W to 155°W and 35°N and 42°N. The patch extends over an indeterminate area of widely varying range depending on the degree of plastic concentration used to define the affected area.

The patch is characterized by exceptionally high relative concentrations of pelagic plastics, chemical sludge and other debris that have been trapped by the currents of the North Pacific Gyre. Its low density (4 particles per cubic meter) prevents detection by satellite photography, or even by casual boaters or divers in the area. It consists primarily of a small increase in suspended, often microscopic, particles in the upper water column.

The great Pacific garbage patch was described in a 1988 paper published by the National Oceanic and Atmospheric Administration (NOAA) of the United States. The description was based on results obtained by several Alaska-based researchers between 1985 and 1988 that measured neustonic plastic in the North Pacific Ocean. Researchers found high concentrations of marine debris accumulating in regions governed by ocean currents. Extrapolating from findings in the Sea of Japan, the researchers hypothesized that similar conditions would occur in other parts of the Pacific where prevailing currents were favorable to the creation of relatively stable waters. They specifically indicated the North Pacific Gyre.

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