Container ships are cargo ships that carry all of their load in truck-size containers, in a technique called containerization. They form a common means of commercial intermodal freight transport.
The World is witnessing a rapid growth of international trade. The question arises, will the United States transportation infrastructure be able to handle the demand? This is afundamental question to ask both the industrial as well as the environmental realms. U.S. ports are attractive sites for world trade because of the relationship of the dollar to foreign currencies and their growing market liberalization. The economic need for the container ships is in resoponse to the growing market demands for greater cargo capacity and speed of cargo ships. The pressure for the use ofthese enormous ships and the pressure for the development of megaports is coming from ocean carriers, exporters and importers
The Environmental Implications
The shipping industry is growing and consequently so are the ships. One of the world's largest container ships was recently produced by the Maersk industry named Svendborg Maersk. This vessel is 347 meters long, 43 meters wide, 24 metersdeep and has a draught of 14.5 meters. Because of the size of these enormous ships, ports are pressured to expand and deepen their channels. The dredging of channels to accomodate the container ships results in the destruction of the bay bottom habitat and the marine life that depends on it. These habitats may never fully recover. The short term risks of dredging the bay include cloudy water whichmay negatively impact the aquatic life. Sediments that are dumped on the bay bottom may also smother the marine life.
A bulk carrier, bulk freighter, or bulker is a merchant ship specially designed to transport unpackaged bulk cargo, such as grains, coal, ore, and cement in its cargo holds. Since the first specialized bulk carrier was built in 1852, economic forces have fueledthe development of these ships, causing them to grow in size and sophistication. Today's bulkers are specially designed to maximize capacity, safety, efficiency, and to be able to withstand the rigors of their work.
Today, bulkers make up 40% of the world's merchant fleets and range in size from single-hold mini-bulkers to mammoth ore ships able to carry 365,000 metric tons of deadweight (DWT).A number of specialized designs exist: some can unload their own cargo, some depend on port facilities for unloading, and some even package the cargo as it is loaded. Over half of all bulkers have Greek, Japanese, or Chinese owners and more than a quarter are registered in Panama. Japan is the largest single builder of bulkers, and 82% of these ships were built in Asia.
A bulk carrier's crewparticipates in the loading and unloading of cargo, navigating the ship, and keeping its machinery and equipment properly maintained. Loading and unloading the cargo is difficult, dangerous, and can take up to 120 hours on larger ships. Crews can range in size from three people on the smallest ships to over 30 on the largest.
Bulk cargo can be very dense, corrosive, or abrasive, and presents safetyproblems: cargo shifting, spontaneous combustion, and cargo saturation can all doom a ship. The use of ships that are old and have corrosion problems has been linked to a spate of bulker sinkings in the 1990s, as have the bulker's large hatchways, important for efficient cargo handling. New international regulations have since been introduced to improve ship design and inspection, and to streamlinethe process of abandoning ship.
The pure ore carrier is characterized as a seagoing single deck ship with two longitudinal bulkheads and a double bottom in between throughout the cargo region, intended for the carriage of ore cargoes in the centre holds only. The cargo hold cubic has commonly been based on a stowage factor of 19.5 to 21.5 cbf/ts at summer draught. These...