Projected climatic changes in storm surge and sea level rise on Viti Levu, Fiji

Abstract:

Projections of storm surges and sea level rise (SLR) are crucial for the future assessment of inundated areas on the coast. The compounding effects of storm surges and SLR are among the main hazards of flooding and extreme events and may bring devastating socioeconomic effects to the Small Island nations. The island of Viti Levu, which is home to 70% of the population in Fiji, is chosen as one of the islands potentially affected due to climate change-driven storm surges and SLR.

The study aims at projecting the role of sea level rise in the inundation of coastal areas, based on the IPCC SROCC scenarios, as well as d4PDF, the mega ensemble climate projections. Storm surge heights forced by the extreme wind speed corresponds to the 1/50 and 1/100 return periods. The affected population based on the simulated inundated area due to storm surge and SLR is estimated, depending on different hazard intensities.

This study finds that the western and northern coasts of the island are the most vulnerable to the above-mentioned compounding effects on the island. SLR contribution to the inundated areas was found to be more significant in general, especially in the case of SLR RCP8.5 and less extreme event scenario. Additionally, mighty western winds may result in the relatively highest number of the potentially displaced population. The future studies aim at including other Oceanic nations and assessing the possible impact on indigenous languages.