Debris

Debris (French, pronounced (IPA) di'bri) is a word used to describe the remains of something that has been otherwise destroyed.

Depending on context, debris can refer to a number of different things.

General
In a general sense, the term debris is used to refer to man-made garbage. The average American discards garbage, also called trash, at the rate of four pounds per day per person, which translates to 600,000 tons per day, or approximately 220 million tons per year. This is almost twice the rate of trash generation per person as most other major countries. Trash levels can be reduced primarily by recycling, re-use, and reduced consumption.

Geological
In geology, debris usually applies to the remains of geological activity including landslides, volcanic explosions, avalanches, mudflows or Jökulhlaups, lahars, and lava eruptions. Geological debris sometimes moves in a stream called a debris flow.

Gustatory
In South Louisiana's Creole and Cajun cultures, debris refers to chopped roast beef. New Orleans tourists can be shocked to hear a customer in a diner order a "debris po-boy"—that is, a submarine sandwich made of chopped roast beef.

Marine
The term Marine debris applies to floating garbage such as bottles, cans, styrofoam, cruise ship waste, offshore oil and gas exploration and production facilities pollution, and fishing paraphernalia from professional and recreational boaters. Marine debris is also called litter or flotsam and jetsam. Objects that can constitute marine debris include used automobile tires, detergent bottles, medical wastes, discarded fishing line and nets, soda cans, and bilge waste solids. In addition to being unsightly, it can pose a serious threat to marine life, boats, swimmers, divers, and others. For example, each year millions of seabirds, sea turtles, fish, and marine mammals become entangled in marine debris, or ingest plastics which they have mistaken for food. As many as 30,000 northern fur seals per year get caught in abandoned fishing nets and either drown or suffocate. Whales mistake plastic bags for squid, and birds may mistake plastic pellets for fish eggs. At other times, animals accidentally eat the plastic while feeding on natural food.

Marine debris most commonly originates from land-based sources. Various international agencies are currently working to reduce marine debris levels around the world.

Meteorological
In meteorology, debris usually applies to the remains of human habitation and natural flora after storm related destruction. This debris is also commonly referred to as storm debris. Storm debris commonly consists of roofing material, downed tree limbs, downed signs, downed power lines and poles, and wind-blown garbage. Storm debris can become a serious problem immediately after a storm, in that it often blocks access to individuals and communities that may require emergency services. This material frequently exists in such large quantities that disposing of it becomes a serious issue for a community. In addition, storm debris is often hazardous by its very nature, since, for example, downed power lines annually account for storm-related deaths.

Space flight
In discussions of space flight, debris usually refers to the remains of spacecraft that have either fallen to Earth or are still orbiting Earth, and is generally known as space debris. Space debris may also consist of natural components such as chunks of rock and ice. The problem of space debris has grown as various space programs have left legacies of launches, explosions, repairs, and discards in both low Earth orbit and more remote orbits. These orbiting fragments have reached a great enough proportion as to constitute a hazard to future space launches of both satellite and manned vehicles. Various government agencies and international organizations are beginning to track space debris and also research possible solutions to the problem. While many of these debris items, ranging in size from nuts and bolts to entire satellites and spacecraft, may fall to Earth, other items located in more remote orbits may stay aloft for centuries. The velocity of some of these pieces of space junk have been clocked in excess of 17,000 miles per hour. A piece of space debris falling to Earth leaves a fiery trail, just like a meteor.

Surgical
In medicine, debris usually refers to biological matter that has accumulated or lodged in surgical instruments and is referred to as surgical debris. The presence of surgical debris can result in cross-infections or nosocomial infections if not removed and the affected surgical instruments or equipment properly disinfected. Disinfection is the process of applying chemical agents or various types of energy to destroy microorganisms.

War debris
In the aftermath of a war, large areas of the region of conflict are often strewn with war debris in the form of abandoned or destroyed hardware and vehicles, unexploded ordnance, bullet casings and other fragments of metal.

Much war debris has the potential to be lethal and continues to kill and maim civilian populations for years after the end of a conflict. The risks from war debris may be sufficiently high to prevent or delay the return of refugees. In addition war debris may contain hazardous chemicals or radioactive components that can contaminate the land or poison civilians who come into contact with it. Many Mine clearance agencies are also involved in the clearance of war debris.

In November 2006 the Protocol on Explosive Remnants of War will come into effect with 92 countries subscribing to the treaty that requires the parties involved in a conflict to assist with the remove of unexploded ordnance following the end of hostilities.

Some of the countries most affected by war debris are Afghanistan, Angola, Cambodia, Iraq and Laos.

Similarly military debris may be found in and around firing ranges and military training areas.

Debris can also be used a cover for military purposes, depending on the situation.