Marine Atlas: Maximizing Benefits for Fiji

current moves southward and cools within Fiji’s wa- ters resulting in the lower temperatures in the south- ern areas. The warm waters of the South Equatorial Current are one of the major drivers in the formation of cyclones in this part of the Pacific Ocean. In fact, in 2016, the high SST fuelled the develop- ment of Cyclone Winston. Although the cyclone devastated Fiji’s islands, it had a positive impact on corals, such as those found on the Coral Coast, as it cooled down the SST, thus helping the corals survive warm water stress. Sea level rise has the potential to negatively impact the low-lying coastal areas of Fiji, through flooding and wave inundation, with consequent shoreline erosion and groundwater salinization. These impacts could lead to a loss of infrastruc- ture and productive land, thereby posing a chal- lenge to livelihoods in the region. Improved data and information on sea level rise are necessary in order to plan effectively for these changes. Sea level rise, as a consequence of global warm- ing, threatens many low-lying regions of the world. The Fifth International Panel on Climate Change assessment projects a global rise in mean sea lev- el for 2081–2100 relative to 1986–2005 of between 0.2 and 0.98 metres, depending on different emis- sions scenarios. Furthermore, the western tropi- cal Pacific Island region is considered one of the most vulnerable regions under future sea level rise (Nicholls and Cazenave, 2010). Sea level rise is not uniform across the western Pacific and is affected by ENSO events. These have a strong modulating effect on inter-annual sea level variability, with low- er 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

Sea level rise has many effects Fortunately for Fiji, its islands have a higher elevation than many of its low-lying Pacific neighbours, meaning that sea level rise is not an issue for much of its land area. However, rising sea levels are still a threat for many coastal communities in Fiji, as evidenced by the low-lying village of Narikoso on Kadavu Island, where seawater has encroached onto areas adds to the current global mean sea level rise due to ocean warming and ice melting (Becker et al., 2012). Fiji is a mix of high volcanic islands and low-lying coral atolls. Vulnerability to sea level rise is influ- enced by coastal geography and prevailing ocean currents. Islands exposed to higher wave energy in addition to sea level rise can experience higher rates of erosion than their more sheltered counter- parts. However, the coral atolls of Fiji 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). An assessment on the vulnerability of mangroves in Suva found that mangrove areas in Tikina Wai showed inherent vulnerability to rising sea levels, partly due to their location on subsiding coastline with low tidal range. However, the area has not experienced significant spatial change in the last few decades (Ellison, 2015).

the land by 15 metres in the last 30 years. Many buildings located close to the sea therefore need to be relocated, with the seven houses closest to the sea a priority. A further 47 houses and other structures will also need to be moved soon due to the rising sea level and risk of floods, especially during cyclones or spring tides. The map indicates that by 2030, Fiji will experience a minimum rise in sea level of 0.11 metres. This is likely to be accompanied by increases in episodes of flooding and wave inundation in some coastal areas. The southernmost islands in the archipelago, the Lau group, will experience the highest increase in sea level rise of 0.16 metres. In general, the Fiji’s main islands are in a zone of lower sea level rise, with bands of increasing sea level rise to the north and south. Pacific Island nations are therefore focused on developing adaptation strategies to address the predicted continued rise in sea level. In the past, atolls and islands, which often rise only a metre above the waves, were flooded by the ocean every couple of decades. That trend has since changed, with an increased frequency in these flooding events. When these flooding events become too frequent, it is difficult for islands to recover, as the land becomes too salty, freshwater reserves in lagoons become undrink- able, and the islands themselves can no longer support human habitation. It is becoming clear that in a warming world, Fiji’s sea will become hotter and higher, with drastic conse- quences for coastal habitats and their inhabitants.

PROJECTED SEA LEVEL RISE RCP 4.5 2030 0.16 metres

Palmyra Atoll (United States of America)

NORTH PAC I F I C OCEAN

0.11 metres

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.

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 FIJI

CLIMATE CHANGE THREATS

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