Garbage patch

Garbage patch may refer to:

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 located roughly between 135°W to 155°W and 35°N and 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.

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. Because of its large area, it is of very low density (4 particles per cubic meter), and therefore not visible from satellite photography, nor even necessarily to casual boaters or divers in the area. It consists primarily of a small increase in suspended, often microscopic, particles in the upper water column.

Discovery

The Great Pacific garbage patch was predicted in a 1988 paper published by the National Oceanic and Atmospheric Administration (NOAA) of the United States. The prediction was based on results obtained by several Alaska-based researchers between 1985 and 1988 that measured neustonic plastic in the North Pacific Ocean. This research 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.

Pacific Ocean

The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south and is bounded by Asia and Australia in the west and the Americas in the east.

At 165.25 million square kilometers (63.8 million square miles) in area, this largest division of the World Ocean—and, in turn, the hydrosphere—covers about 46% of the Earth's water surface and about one-third of its total surface area, making it larger than all of the Earth's land area combined.

The equator subdivides it into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the Galápagos and Gilbert Islands, while straddling the equator, are deemed wholly within the South Pacific. The Mariana Trench in the western North Pacific is the deepest point in the world, reaching a depth of 10,911 metres (35,797 ft).

The eastern Pacific Ocean was first sighted by Europeans in the early 16th century when Spanish explorer Vasco Núñez de Balboa crossed the Isthmus of Panama in 1513 and discovered the great "southern sea" which he named Mar del Sur. The ocean's current name was coined by Portuguese explorer Ferdinand Magellan during the Spanish circumnavigation of the world in 1521, as he encountered favourable winds on reaching the ocean. He called it Mar Pacifico, which in both Portuguese and Spanish means "peaceful sea".

Municipal solid waste

Municipal solid waste (MSW), commonly known as trash or garbage in the United States and as refuse or rubbish in Britain, is a waste type consisting of everyday items that are discarded by the public. "Garbage" can also refer specifically to food waste, as in a garbage disposal; the two are sometimes collected separately.

Composition

The composition of municipal solid waste varies greatly from municipality to municipality (country to country) and changes significantly with time. In municipalities (countries) which have a well developed waste recycling system, the waste stream consists mainly of intractable wastes such as plastic film, and unrecyclable packaging materials. At the start of the 20th century, the majority of domestic waste (53%) in the UK consisted of coal ash from open fires. In developed municipalities (countries) without significant recycling activity it predominantly includes food wastes, market wastes, yard wastes, plastic containers and product packaging materials, and other miscellaneous solid wastes from residential, commercial, institutional, and industrial sources. Most definitions of municipal solid waste do not include industrial wastes, agricultural wastes, medical waste, radioactive waste or sewage sludge. Waste collection is performed by the municipality within a given area. The term residual waste relates to waste left from household sources containing materials that have not been separated out or sent for reprocessing. Waste can be classified in several ways but the following list represents a typical classification:

Patch

Patch may refer to:

Computing

Electronics

Geography and landscape