A comprehensive analysis of the rising sea levels in Tuvalu

Abstract

The purpose of this study is to comprehend the sea level rise pattern around Tuvalu. This objective is accomplished by investigating the relative monthly average mean sea levels (MSL) recorded by tide gauges. In addition to the historical and contemporary tide gauges located in Tuvalu, we analyze the MSL data also from tide gauges in Pacific islands and atolls, as well as the long-term trend tide gauges in Honolulu and Sydney, to enhance and reinforce the findings. The analysis is complemented by information on subsidence obtained from the global positioning system (GPS) monitoring. The significant increase in sea level observed at Tuvalu’s current tide gauge is attributed more to multidecadal oscillations, significantly affecting short-term records, and the subsidence of the tide gauge, rather than the global thermosteric contribution. The residual rate of sea level rise is likely influenced by other factors, such as changes in circulation within the lagoon or other local anthropogenic biases. The suggested analysis aligns with prior research, reinforcing the perspective that the sea levels are gently rising and the surfaced area of Pacific islands and atolls is not diminishing, contrary to inaccuracies found in selective studies that emphasize certain data while disregarding others.