These regional projections used similar methodology (documented in Mc Innes ) for the period 1980 to 2009 at two locations (1.
Historical sea-level data and projections for the 21st century for the Solomon Islands are available from a recent assessment of climate change in the Pacific (Australian Bureau of Meteorology and CSIRO 2014).
Isabel: latitude −7.33312, longitude 159.00030) were sourced from the CAWCR Wave Hindcast 1979–2010 data (Source: Australian Bureau of Meteorology and CSIRO as described by Durrant 2013).
2016 dating solomon island
Only two of the sites (Nuatambu and Mararo) are populated, whilst the sites in Isabel and Roviana have no known history of continuous human habitation. (a) Map of the Solomon Islands relative to south Pacific region indicating study sites (•) in Choiseul (Nuatambu), Malaita (Mararo) and Isabel Provinces, (b) inset of study sites across northern Isabel. Summary data of island area and percentage decadal change at seven atoll sites in the Central Pacific (modified from Mc Lean and Kench 2015) and Solomon Islands (this study).
The islands in Roviana are used on a daily basis by nearby communities for fishing, whilst the islands in Isabel are infrequently visited on a weekly-monthly basis by fishers with no significant disturbance of coastal vegetation by fishers observed. Island-change data within the highlighted ±3.0% band width is not considered significant.
Due to their extreme vulnerability, coral atolls have been the main focus for assessing island responses to sea-level change. The islands of Zollies, Rehana, Kakatina and Rapita all disappeared between 19 (table 1).
Whilst shoreline recession has been documented on atolls over past decades, the majority of studies have not specifically demonstrated evidence linking shoreline recession to recent sea-level rise (Webb and Kench 2010, Le Cozannet 2014). Severe coastal recession on the eastern shoreline of Nuatambu village occurred between 20 resulting in ten houses being lost to the sea (supplementary figure 2).
The higher local rate of historical rise is the result of both a larger global averaged rate of sea-level rise (Church and White 2011) and also stronger trade winds since 1990 (Merrifield and Maltrud 2011) which are directly related to the decreasing Pacific Decadal Oscillation index (Zhang and Church 2012).
These PDO and ENSO conditions may ease in the Solomon Islands in coming decades to produce sea-level rise rates closer to the global average.
How islands and the communities that inhabit them respond to climate change and particularly sea-level rise is a critical issue for the coming century. Islands in Roviana did not experience a change in the rate of loss over the study period, with island loss rates averaging 0.1% pa, −0.2% pa and 0.1% pa across the three time periods.50% loss moved in a south, south-east or easterly direction between 19.
Small remote islands are viewed as particularly vulnerable (Wong 2014). The centroid of Kale on Isabel was displaced 293 m on a bearing of 207° between 19 before the remaining sediment was transported off the reef platform into deep water.
Rates of shoreline recession are substantially higher in areas exposed to high wave energy, indicating a synergistic interaction between sea-level rise and waves. A further six islands on Isabel had declined in area by more than 20% between 19.
Understanding these local factors that increase the susceptibility of islands to coastal erosion is critical to guide adaptation responses for these remote Pacific communities. Hetaheta, Sogomou and Kale experienced the largest loss of island area between 19, declining in size by 155 790 m Figure 2. (a) Coastline recession on Sogomou Island between 19, (b) view from the eroding eastern end of Sogomou looking back towards the remainder of the island, (c) coastline recession on Kale Island between 19.
While there is significant interannual variability, the tide gauge and altimeter data indicate a rapid rise in sea levels in the Solomon Islands between 19 of about 15 cm (average of 7 mm yr).