Pacific News Minute: Study Shows Most Reef Islands Remain Stable or Grow Despite Sea Level Rise

Jan 28, 2016

Credit Marty B / Flickr

For many years, we've heard that climate change will make the low lying islands of many Pacific nations uninhabitable over the next few decades. Now a new study shows that despite the effects of sea level rise and more powerful storms, most reef islands have persisted and even grown. But as we hear from Neal Conan in the Pacific News Minute, prospects for many Pacific Island nations remain gloomy.

In January, 1958, Typhoon Ophelia devastated Jaluit Atoll, in the Marshall Islands tearing away more than 5% of the land mass. Almost 60 years later, Jaluit is bigger than it was before the storm hit.

A paper by researchers from the University of Auckland published in the February issue of the journal Geology reinforces earlier studies that fly in the face of expectations. Overall, about twenty percent of coral reef islands are shrinking, 40% are holding their own, and 40% are growing. In Jaluit, results are even more striking: Co-Authors Murray Ford and Paul Kench used aerial photographs and satellite images to show that 73 of 87 islands got larger between 1976 and 2006.

While storms wash away large amounts of sand, it turns out that they also generate huge amounts of coral rubble that waves pulverize into new sand.  As ocean coastlines erode, the lagoon side builds up.

That's good news for lightly populated islands with few permanent structures...but most of the people of low lying Pacific Island nations live on what are now urbanized islands where roads, sea walls, electricity and water systems and many buildings are fixed and vulnerable right now. In the long run, higher water temperature will kill live corals, while increased ocean acidity slowly dissolves the reefs that give all these islands life.