A new study produced by researchers at the University of Auckland concludes that forecasts about the impact of climate change on some low-lying islands have failed to take into account key factors and thus have overstated the danger posed to inhabitants. The most "counterintuitive" finding in the study: the Pacific island nation of Tuvalu — the poster child of "sinking" island fears — is not only not shrinking, it's actually growing in size.
The study, highlighted by Phys.org, "examined changes in the geography of Tuvalu's nine atolls and 101 reef islands between 1971 and 2014, using aerial photographs and satellite imagery." Over that period, "eight of the atolls and almost three-quarters of the islands grew."
In total, rather than shrinking in land mass, Tuvalu's total land area increased by 2.9%. This increase is particularly "counterintuitive" because the area in which Tuvalu is located is supposed to have suffered a rise in sea levels that are "twice the global average."
"We tend to think of Pacific atolls as static landforms that will simply be inundated as sea levels rise, but there is growing evidence these islands are geologically dynamic and are constantly changing," said co-author Paul Kench, Head of the School of Environment at the University of Auckland. "The study findings may seem counter-intuitive, given that (the) sea level has been rising in the region over the past half century, but the dominant mode of change over that time on Tuvalu has been expansion, not erosion."
Based on their research, said Kench, his team projects "a markedly different trajectory for Tuvalu's islands over the next century than is commonly envisaged." While noting that the habitability of the island nation is impacted by a range of factors, Kench said "loss of land is unlikely to be a factor in forcing depopulation of Tuvalu."
When the University of Auckland researchers first launched the Royal Society of New Zealand Catalyst Fund-backed study in 2017, Kench explained the way in which they planned to test their theories.
"Over recent decades, it has become a commonly held belief that nations such as the Maldives, Chagos or Marshall islands are simply going to vanish as sea levels rise," he said. "But our research would suggest it is in fact a commonly held misconception, and what we actually believe will happen is that as sand and gravel shift it will form a natural barrier against the sea. This is the first time we have been able to test that theory in a laboratory facility, and by replicating the conditions these remote nations face we hope to demonstrate the resilience of the islands but also enable them to appropriately prepare for the future challenges they may face."