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Republic of Kiribati Top Impact Other Impacts
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Rising sea levels and ocean temperatures caused by global warming threaten the people, economy, and very existence of Kiribati, a low-lying island nation composed of coral atolls in the tropical Pacific.1 |
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Key Facts Situated just west of the International Date Line, Kiribati was among the first nations to enter the new millennium. It is also one of the first countries in danger of becoming uninhabitable owing to climate change.10
Details The Republic of Kiribati is a low-lying Pacific Island nation situated just west of the International Date Line. It is an archipelago of 33 islands—21 of them inhabited—with a total land area of 313 square miles (811 square kilometers).2 The islands are atolls—each one a ring-shaped coral reef that encircles a lagoon. Because atolls are naturally low-lying, and have a have a high ratio of coastline to land area, they are especially vulnerable to sea-level rise and storm surges.3 Kiribati is one of five countries composed entirely of atolls.4 Global warming contributes to sea-level rise in two major ways: through melting of glaciers and ice sheets and expansion of ocean water as it warms. During the twentieth century, global mean sea level rose at an average of 0.07 inches (1.8 millimeters) per year.5 However, from 1993 to 2003 the average rate of sea-level rise increased to around 0.12 inches (3.1 millimeters) per year.6 With most of its land only a few feet above sea level, Kiribati has already seen growing damage from storms and flooding. Some of the nation's uninhabited islets have even vanished beneath the Pacific.7 Most of Kiribati's 112,000 people live on the atoll of Tarawa, where the capital (also called Tarawa) is located.2,8 The city of Tarawa is less than 9.8 feet (3 meters) above sea level.8 Kiribati's president has alerted the United Nations to the challenges the country faces from beach erosion, sea-level rise, and contamination of freshwater.9 Rising sea surface temperatures pose an additional danger to Kiribati.10 Coral reefs—which are critical to sustaining atolls and their islands—are very sensitive even to small increases in ocean temperature, which can cause coral bleaching.11 Corals are marine animals. Their spectacular coloration comes from symbiotic algae, which also nourish them. When increases in ocean temperature or ultraviolet light stress the corals, they lose algae and turn white. Without the algae, corals can starve, their growth and reproduction can decline, and their vulnerability to disease can increase. If the stress is sustained long enough, the corals die.12 In 1998—a record-breaking year for sea surface temperatures—coral bleaching spiked worldwide.10 Severe bleaching also occurred in 2002 and 2006.13,14 What the Future HoldsGlobal warming threatens to render Kiribati unlivable well before it is completely submerged.10 If our heat-trapping emissions continue at today's rates, rising ocean waters may shrink Kiribati's land area, increase storm damage, and threaten its freshwater reserves. The I-Kiribati people risk losing their homes, country, and heritage. Climate change could also undermine the sovereignty of the Republic of Kiribati.3,10 Scientists expect a warming global climate to cause further sea-level rise over this century and beyond.15,16 If we do nothing to reduce our carbon emissions,17 global sea level is projected to rise as high as 23 inches (59 centimeters) over recent average levels by the end of this century.18 If, on the other hand, we make significant efforts to reduce our emissions,17 sea-level rise between now and the end of the century could be at most 15 inches (38 centimeters).18 Recent evidence of higher rates of global sea-level rise from melting ice on land suggests that these projections—based largely on a warming ocean—may be low.5,19 Given recent accelerated shrinking of glaciers and ice sheets, scientists now think that a rise of 2.6 feet (80 centimeters) is plausible—and that as much as 6.6 feet (2 meters) is possible though less likely.20 Many countries are at risk of seawater incursion, particularly those with major river deltas, low-lying areas, and coastal regions. Severe and frequent coral bleaching caused by warming ocean waters could hinder the growth of Kiribati's reefs, compounding the dangers of sea-level rise.10 If our heat-trapping emissions continue to increase at today's rates, sea surface temperatures are projected to rise as much as 5.4° F (3° C) by the end of the century.13,17 Scientists project that by 2080, the risk of flooding in Pacific atoll countries is likely to be roughly 200 times greater than at the start of this century.21 Without any adaptation, Kiribati could lose about 34 percent of its 1998 GDP by 2050 because of climate change and sea-level rise.8 Adaptations such as desalinizing the saltwater that intrudes into freshwater aquifers are technologically possible. However, given that Kiribati and other low-lying island countries, including the Maldives and Tuval, are among the poorest nations in the world,22 they are unlikely to be able to afford such measures. Endnotes
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Global Warming Effects Around the World
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