Marine Atlas: Maximizing Benefits for Solomon Islands

sea level rise are necessary in order to plan effectively for these changes.

Islands exposed to higher wave energy in ad- dition to sea level rise can experience higher rates of erosion than their more sheltered counterparts. However, the coral atolls of Solomon Islands may be able to adjust their size, shape and position in response to sea level rise, as has been suggested for other reef islands such as Funafuti Atoll in Tuvalu (Kench et al., 2015). Vertical reef accretion that occurs in response to sea level rise may be able to prevent the significant increases

in shoreline wave energy and wave-driven flooding that are predicted in the absence of reef growth (Beetham et al., 2017). The map indicates that by 2030, Solomon Islands will experience a minimum rise in sea level of 0.14–0.16 metres. This is likely to be accompanied by increases in episodes of flooding and wave inundation in some coastal areas. In general, the main islands of Solomon Islands are in a zone of lower

these flooding events become too frequent, it will be difficult for the islands to recover. The land becomes too salty, freshwater re- serves in lagoons become undrinkable and the islands themselves are no longer able to support human habitation. It is becoming clear that in a warming world, Solomon Islands’ sea will become hotter and higher, with drastic consequences for coastal habitats and their inhabitants.

sea level rise, with sea levels increasingly rising in the south. Pacific Island nations are therefore focused on developing adaptation strategies to address the predicted contin- ued rise in sea level. In the past, ocean waves only flooded atolls and islands (often just one metre above the waves) every couple of decades. This trend has since changed, with flooding now beginning to occur more frequently. When

Sea level rise, as a consequence of global warming, threatens many low-lying regions of the world. The Fifth International Panel on Climate Change assessment projects a global rise in mean sea level for 2081–2100 relative to 1986–2005 of between 0.2 and 0.98 metres, depending on different emis- sions scenarios. Furthermore, the western tropical Pacific Island region is considered one of the most vulnerable regions under future sea level rise (Nicholls and Ca- zenave, 2010). Sea level rise is not uniform across the western Pacific and is affect- ed by ENSO events. These have a strong modulating effect on inter-annual sea level variability, with lower than average sea level during El Niño and higher than average during La Niña events (of ±20–30 cm). In addition, there is also an observed low-fre- quency (multi-decadal) variability, which in some areas adds to the current global mean sea level rise due to ocean warming and ice melting (Becker et al., 2012). Solomon Islands is a mix of predominantly high volcanic islands and several low-lying coral atolls. Vulnerability to sea level rise is in- fluenced by coastal geography and prevailing ocean currents. High volcanic islands with significant infrastructure along the coastal zone are also vulnerable to rising sea levels.

PROJECTED SEA LEVEL RISE RCP 4.5 2030 0.16 meters

Palmyra Atoll (United States of America)

NORTH PAC I F I C OCEAN

0.11 meters

Howland and Baker Islands (United States of America)

Exclusive Economic Zones (EEZ)

Jarvis Island (United States of America)

Copyright © MACBIO Map produced by GRID-Arendal Sources : Becker et al, 2009; Claus et al, 2016; CSIRO Australia, 2014; Smith and Sandwell, 1997.

Visualizing rising sea levels Five islands have already disappeared in Solomon Islands due to coastal erosion and rising sea levels. A further six reef islands have been severely eroded with 10 houses being swept from one island into the sea between 2011 and 2014. Solomon Islands is considered a sea-level hotspot, as its waters are rising three times higher than the global average. As a result, some villages have already been relocated, with more to follow.

Disputed area Matthew and Hunter Islands: New Caledonia / Vanuatu

SOUTH PAC I F I C OCEAN

Australia

Norfolk Island (Australia)

New Zealand

MAXIMIZING BENEFITS FOR SOLOMON ISLANDS

CLIMATE CHANGE THREATS

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