Rising sea levels threaten tiny Marshall Islands

MAJURO, Marshall Islands --

ATOLLS AT RISK

Consisting of 29 atolls and five free-standing islands spread over vast distances in the Pacific Ocean, the Marshall Islands is home to 70,000 residents living on a total land area similar to that of Washington D.C. The highest point anywhere in the chain is 10 meters above sea level, but most places rise only about 2 meters above sea level. Even small increases in ocean levels can have a big impact.

OCEANS RISING

Scientists who contributed to the UN's Intergovernmental Panel on Climate Change estimate global sea levels have risen by about 19 centimeters since 1900. However, they say sea levels are rising much faster than average in the western Pacific, where the Marshall Islands is located. The common assumption that melting glaciers and ice sheets would cause a uniform rise worldwide - much like filling a bathtub with more water - is incorrect, according to the panel. They say ocean currents, winds and the Earth's gravity all contribute to an uneven rise. The panel says sea levels are likely to rise on average by about another 30 to 90 centimeters by the end of this century.

KING TIDES

Marshallese people say "king tides," which cause flooding, are getting worse. The term is often used to describe the highest tides of the year, when the alignment of the Earth, moon and sun combine to produce the most extreme tidal effects. Waves and storms can also increase the effects of king tides. As well as causing huge inconvenience to islanders, the flooding from king tides can accelerate erosion and contaminate ground water with salt, killing trees and crops. Scientists say it is these flooding events rather than an overall rise in the sea level that may eventually force people from their homes.

CORAL BLEACHING

People in the Marshall Islands say they've noticed other effects from global warming, including coral bleaching. That's when warmer water temperatures cause coral to turn white. Coral can survive an occasional bleaching but is at an increased risk of dying. The coral reefs around the Marshall Islands form an important barrier from ocean waves. Islanders say they've also noticed unusually hot weather this year, as the region grapples with a strong El Nino weather cycle.

PARIS TALKS

More than 120 world leaders including President Barack Obama plan to meet in Paris next week as they seek a deal to cut back on global emissions of heat-trapping gases. A major goal of the talks is to limit global warming in air temperatures to below 2 degrees Celsius by the end of the century. Some leaders, including those from the Marshall Islands, are pushing for a lower target of 1.5 degrees Celsius. The recent Paris terrorist attacks have prompted organizers to make some changes but the talks are still scheduled to go ahead.