THE PACIFIC OCEAN—named the "peaceful sea" by Ferdinand Magellan, a Portuguese explorer leading a Spanish expedition—is the largest ocean in the world, covering 65.3 million sq. mi. (169.2 million sq. km.), encompassing 32 percent of the total surface of the Earth, and holding 46 percent of the Earth’s water. Altogether, there are 25,000 islands in the Pacific, the vast majority south of the equator, which bisects the ocean.
Rising sea levels
Global warming and climate change pose many real threats to the Pacific Ocean. The major focus of much attention around the world has been on the rising water levels, which is likely to inundate many of the low-lying Pacific Islands. Independent countries such as Fiji, Kiribati, the Federated States of Micronesia, Nauru, Palau, Samoa, and Tuvalu risk losing the vast majority of their land if the rising world temperature continues to raise the water level of the ocean. Atolls in French Polynesia and in Wallis and Futuna are also under threat. In addition to those places, all the countries in the Pacific have an increased risk of flooding, which could lead to permanent soil loss, as well as an increased risk of the prevalence of insect-borne diseases such as malaria and dengue fever as mosquitoes find further breeding grounds. The rising sea levels also threaten mangrove swamps in many areas, including off the northeastern coast of Australia, and in many Pacific Islands, with 13 percent of the world’s mangrove swamps at risk of being lost.
For this reason, many of the countries in the Pacific have been at the forefront of urging countries around the word to embrace the Kyoto Protocol and limit carbon dioxide emissions. The Republic of Nauru, the country with the highest per capita rate of carbon dioxide emissions in the Pacific, went as far as adding a long addenda to the Kyoto Protocol, arguing that it did not feel that the protocol went far enough. Two U.S. territories in the Pacific, Guam and American Samoa, have considerable carbon dioxide emissions. The Solomon Islands, Papua New Guinea, and Vanuatu have, respectively, the lowest rates of carbon dioxide emissions in the Pacific, at rates similar to that of many African countries.
Changes to marine life
Other problems in the Pacific Ocean regarding global warming focus on the marine flora and fauna. The area most dramatically affected has been the bleaching of coral reefs around the Pacific, with studies by the International Ocean Institute of the University of the South Pacific in Fiji conducting surveys of coral reefs in the southwest Pacific as part of the International Coral Reef Initiative. In many cases, the damage to coral reefs has come from overpopulation, and through overexploitation through tourism, but even many reefs located in remote parts of the Pacific have experienced bleaching, showing that the damage can be ascribed as much to global warming as to other problems.
As well as coral reefs, there have been significant changes to the marine life, especially the fish in the Pacific. The most dramatic changes have been the reduction in the diversity of fish shoals, as well as the decline in the number of fish, the latter probably as much from overfishing as from global warming. However, there still remain large numbers of tuna fish and also some cluepoids in the central part of the Pacific Ocean, as well as sardines and jack mackerel along the coast of Chile, anchovy off the coast of Ecuador and Peru, mackerel and Saury off the Pacific coasts of Mexico and the United States, and sardine and salmon off the Pacific coast of Canada.
Some 4 percent of the ozone in the Earth’s stratosphere is lost each decade, and a hole has appeared over Antarctica, leading to a higher risk of skin cancer from ultraviolet light in places such as Australia, New Zealand, Chile, and southern Argentina. Although there has been a great focus on their effects on humans, the ultraviolet rays have also been linked to the reduction in the plankton population in the southern part of the Pacific Ocean. The removal of much of the plankton has major effects on the food chain throughout the Pacific, especially on the whale population, which has been growing following a moratorium on commercial whaling in 1986, although Japan continues whaling for ostensibly "scientific" reasons.
One last major area of problems in the Pacific Ocean through global warming and climate change has been changes in the ocean currents, which have been caused by the rise in the temperature of the water. Although few Polynesians travel long distances in traditional canoes, as they did about 1,000 years ago during the populating of many of the islands, the currents are very important, not just for shipping, but also for the movement of marine life such as shoals of fish. The warmer temperature and changes in the current seem to have had major effects on the spawning process of some fish species, and this may be responsible for a decline in the population of certain fish.
Although there is a serious worry about global warming and its effects on the Pacific Ocean, one report in 1997 by scientists from the Lamont-Doherty Earth Observatory at Columbia University claims that the vast size of the Pacific Ocean has led to the dissipation of many of the effects of global warming and climate change, and might account for the fact that the world’s temperature has only risen half the level of that in some projections.