We’ve mentioned several times here on WUWT that the claims about sea level rise and sinking islands are overblown. For example, this idiotic publicity stunt by the Maldivian government, signing a legal declaration underwater, demonstrates just how far some people are willing to prostitute their victimhood for financial gain. The MO: You other countries warmed the earth, raising sea level which threatens our island. Pay up sucka!
Yeah, well, that scam is now going the way of Nigerian email.
From TV New Zealand:
An Auckland University researcher has offered new hope to the myriad small island nations in the Pacific which have loudly complained their low-lying atolls will drown as global warming boosts sea levels.
Geographer Associate Professor Paul Kench has measured 27 islands where local sea levels have risen 120mm – an average of 2mm a year – over the past 60 years, and found that just four had diminished in size.
Working with Arthur Webb at the Fiji-based South Pacific Applied Geoscience Commission, Kench used historical aerial photographs and high-resolution satellite images to study changes in the land area of the islands.
They found that the remaining 23 had either stayed the same or grown bigger, according to the research published in a scientific journal, Global and Planetary Change.
“It has been thought that as the sea level goes up, islands will sit there and drown,” Prof Kench told the New Scientist. “But they won’t.
“The sea level will go up and the island will start responding.
One of the highest profile islands – in a political sense – was Tuvalu, where politicians and climate change campaigners have repeatedly predicted it will be drowned by rising seas, as its highest point is 4.5 metres above sea level. But the researchers found seven islands had spread by more than 3 percent on average since the 1950s.
One island, Funamanu, gained 0.44 hectares or nearly 30 percent of its previous area.
And the research showed similar trends in the Republic of Kiribati, where the three main urbanised islands also “grew” – Betio by 30 percent (36ha), Bairiki by 16.3 percent (5.8ha) and Nanikai by 12.5 percent (0.8ha).
Webb, an expert on coastal processes, told the New Scientist the trend was explained by the fact the islands mostly comprised coral debris eroded from encircling reefs and pushed up onto the islands by winds and waves.
The process was continuous, because the corals were alive, he said.
In effect the islands respond to changes in weather patterns and climate – Cyclone Bebe deposited 140ha of sediment on the eastern reef of Tuvalu in 1972, increasing the main island’s area by 10 percent.
But the two men warned that while the islands were coping for now, any acceleration in the rate of sea level rise could re-instate the earlier gloomy predictions.
No one knows how fast the islands can grow, and calculating sea level rise is an inexact science.
Climate experts have generally raised estimates for sea level rise – the United Nations spoke in late 2009 of a maximum 2 metre rise by 2100, up from 18-59cm estimated in 2007.
Here’s the abstract and the link to the paper. (corrected, the New Scientist provided link was originally bad)
The dynamic response of reef islands to sea level rise: evidence from multi-decadal analysis of island change in the central pacific
a South Pacific Applied Geoscience Commission, SOPAC. Fiji
b School of Environment, The University of Auckland, Private Bag 92019, Auckland, New Zealand
Received 22 February 2010; accepted 13 May 2010. Available online 21 May 2010.
Low-lying atoll islands are widely perceived to erode in response to measured and future sea level rise. Using historical aerial photography and satellite images this study presents the first quantitative analysis of physical changes in 27 atoll islands in the central Pacific over a 19 to 61 year period. This period of analysis corresponds with instrumental records that show a rate of sea level rise of 2.0 mm.y-1 in the Pacific. Results show that 86% of islands remained stable (43%) or increased in area (43%) over the timeframe of analysis. Largest decadal rates of increase in island area range between 0.1 to 5.6 hectares. Only 14% of study islands exhibited a net reduction in island area. Despite small net changes in area, islands exhibited larger gross changes. This was expressed as changes in the planform configuration and position of islands on reef platforms. Modes of island change included: ocean shoreline displacement toward the lagoon; lagoon shoreline progradation; and, extension of the ends of elongate islands. Collectively these adjustments represent net lagoonward migration of islands in 65% of cases. Results contradict existing paradigms of island response and have significant implications for the consideration of island stability under ongoing sea level rise in the central Pacific. First, islands are geomorphologically persistent features on atoll reef platforms and can increase in island area despite sea level change. Second; islands are dynamic landforms that undergo a range of physical adjustments in responses to changing boundary conditions, of which sea level is just one factor. Third, erosion of island shorelines must be reconsidered in the context of physical adjustments of the entire island shoreline as erosion may be balanced by progradation on other sectors of shorelines. Results indicate that the style and magnitude of geomorphic change will vary between islands. Therefore, Island nations must place a high priority on resolving the precise styles and rates of change that will occur over the next century and reconsider the implications for adaption.
(Corrected) Link to paper (paywall) is here
h/t to Purakanui