News: SEA CHANGE?

Warming makes islands grow,

not shrink, says study

   An artist's rendition, based on satellite images, of an island in Tuvalu in the South Pacific. The dotted line and the solid line indicate the coast lines in 1984 and 2004 respectively.

Wellington: New research has cast doubt on warnings that rising sea levels caused by climate change are slowly inundating low-lying Pacific islands.

         

          Scientists have studied 27 lowp0lying Pacific islands, comparing aerial photos from 60 years ago with modern satellite images, according to an article published in the New Scientist.

          Paul Kench of the University of Auckland in New Zealand and Arthur Webb at the South Pacific Applied Geo science Commission in Fiji found only four of the 27 islands declined in size despite an average rise in sea level of 12cm during the 60-year period.

        Half of the rest had remained the same size and the other half had increased in size. Kench said this shows that islands respond in different ways to climate change and rising seas. "One thing our results tell us there is no one model fits all kind of scenario," Kench said.

        It was important to have a sensible debate over the impact of climate change, "rather than just saying the sea level's going up and the islands must all disappear"

       The study says some islands are growing because waves, currents and winds are pushing coral debris from the surrounding reefs onto the shore. Although this study only involved studying the land area,  Kench said his previous research had shown cyclones and storms-which are predicted to become more frequent with climate change-also often played and important role in increasing the height of islands. "I've been in Tuvalu and know when cyclones hit Tuvalu, the waves go right across the island and in doing so, they are ripping up coral from the reef and beach and depositing them on the island surface.

       "So there's a natural mechanism of how these islands can rise vertically and in many cases can deep pace with sea level rise projected over the next century", Kench said.

        The study found that seven islands in one of Tuvalu's nine atolls have grown in area by more than three percent on average since the 1950s. With one island expanding nearly 30%.