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Maritime Transport



The transportation of raw materials and finished goods is an important part of the supply chain. Transportation can include air, rail, road, and maritime shipping. The last of these, maritime transportation, is extremely important to the US economy as approximately 95 percent of all foreign trade is carried by this mode of transport. Ports in the US move around two billion tons of freight in a single year. Maritime transportation contributed over $222 billion annually to the US gross domestic product (GDP) and provided more than 2.5 million jobs.


Exporting goods to nations across the world is very important to the US economy and the container vessel is a key part in making this happen. The container vessel is far more efficient in transporting goods over large distances than air transportation. The larger container vessels can contain large items that cannot physically fit, either by weight or size, on an aircraft. In fact it would take over a hundred aircraft to move the same freight as contained in one container vessel. Each year the US moves 2.3 billion tons of cargo.

Container Vessels

Container vessels are an important part of maritime transportation. The container vessel did not come into existence until the 1950’s and their appearance revolutionized the shipping industry. The new type of vessel ended the practice of having to load individual items and restraining them aboard the ship. The standardized container allowed the material to be place in the container and then the filled container loaded on to the ship. It is estimated that over ninety percent of the non-bulk material moved on the ocean is transported on container vessels. The average container vessel can accommodate 15,000 containers of material. These containers can be quickly loaded and unloaded so that the vessel can be used more efficiently by its owners, as well as reducing the delivery times for shipments.

Bulk Cargo Vessels

The bulk cargo vessel is used to transport unpacked material. The hold of a bulk cargo vessel can hold raw materials, such as iron ore, grain, cement, coal, or liquid materials, such as chemicals. Bulk vessels make up over seventy percent of the world’s fleet. The US Port of South Louisiana is the largest bulk cargo facility in the world. The port is 54 miles in length and is used to export 60 percent of all raw grains from the US. Over 4,000 oceangoing vessels and 55,000 barges call at the Port of South Louisiana each year, which makes it the top ranked in the US for export tonnage and total tonnage.

Environmental Aspects

Maritime transportation is not only more efficient that air transport, but it is more environmentally friendly. It is estimated that on average a container ship emits around forty times less Carbon Dioxide (CO2) than a large freight aircraft and three times less than a commercial vehicle on the highway. Container shipping is also estimated to be two and a half times more energy efficient than rail and seven times more so than road.

The shipping industry has been cited over the years for environmental issues which occurred as a result of maritime transportation. After unloading bulk loads such as coal, nitrates and mineral products, marine vessels require cleaning. This is not done in the ports, but in international waters, resulting in significant discharges in the ocean. It is estimated that for every million tons of oil carried, one ton is spilled through washouts. Annually, an average of 1.1 million tons of oil in the ocean comes from discharges and 400,000 tons are spilled. Agencies have found that the petroleum products cause the most destruction of aquatic plant and animal life and of shore ecosystems. Container ships are not immune to environmental problems as a great many containers are lost at sea and these can cause environmental problems on the ocean floor.

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