Tropical Pacific island nations already contend with the gradual rise in sea level caused by the melting of the world's ice and the warming of the oceans.

Now these nations would also have to experience more frequent sea level fluctuations, which could be attributed to the El Niño phenomenon and the associated response of the Pacific wind to this weather pattern.

An unusually powerful El Niño is expected to occur this year. The phenomenon is known to cause the waters in the Pacific to become warmer and circulate less vigorously, events that lead to weather changes all over the globe.

Researchers of a new study revealed that with more extreme sea-level swings occurring more frequently, the islands could see increased coral destruction associated with a foul-smelling tide Samoans call "Taimasa," coastline erosion and flooding once sea levels rebound.

Using climate models, study researcher Matthew Widlansky from the International Pacific Research Center of the University of Hawai'i and colleagues projected that at the end of this century, the intensified wind impacts associated with strong La Niña and El Niño events could possibly double the occurrence of extreme sea level fluctuations and that this would particularly affect the tropical southwestern Pacific.

"The possibility of more frequent flooding in some areas and sea level drops in others would have severe consequences for the vulnerable coastlines of Pacific islands," the researchers said.

The researchers said that the result of their study, which was published in Science Advances on Sept. 25, is consistent with earlier findings that show the atmospheric effects of both the La Niña and El Niño events could become stronger and would occur more frequently in the future due to the warming climate as climate change magnifies the effect of these events.

"Climate change will enhance El Niño-related sea level extremes, especially in the tropical southwestern Pacific, where very low sea level events, locally known as Taimasa, are projected to double in occurrence," the researchers wrote in their study.

"Throughout the tropical Pacific, prolonged interannual sea level inundations are also found to become more likely with greenhouse warming and increased frequency of extreme La Niña events."

The researchers hope that better predictability of the rising sea levels and sea level fluctuations could help Pacific island communities adapt to the effects of climate change and shorter-term climate events.

Photo: Andrew Moore | Flickr