Changes of Extreme Sea Level in 1.5 and 2.0°C Warmer Climate Along the Coast of China

Jianlong Feng,Qiulin Liu,Kexiu Liu,Hui Wang,Delei Li,Huan Li

doi:10.3389/feart.2018.00216

Abstract

Using hourly sea level data from 15 tide gauges along the Chinese coast and sea level data of three simulations of the Coupled Model Intercomparison Project Phase 5 (CMIP5), we assessed the changes and benefits of the extreme sea level of limiting warming to 1.5°C instead of 2.0°C. Observations show that the extreme sea level has risen with high confidence during the past decades along the coast of China, while the mean sea level change, especially the long-term change plays important roles in the changing process of extreme sea levels. Under the 1.5°C and 2.0°C warming scenarios, the sea level will rise with fluctuations in the future, so will the return levels of the extreme sea levels. Compared with the 1.5°C warming condition, the return levels under the 2.0°C warming condition will rise significantly at all tide gauges along the Chinese coast. The results indicate that a 0.5°C warming will bring much difference to the extreme sea levels along the coast of China. It is of great necessity to limit anthropogenic warming to 1.5°C rather than 2.0°C, as proposed by the Paris Climate Agreement, which will greatly reduce the potential risks of future flood disasters along the coast of China and is beneficial for risk response management.

Highlights

China has the largest coastal population in the world, with more than 40% people living in the coastal area, where the extreme sea level disasters occur frequently and have caused serious negative impacts
Percentile analysis method has been widely used to assess the extreme sea level changes (Menéndez and Woodworth, 2010; Feng et al, 2015; Marcos and Woodworth, 2017). 99.9, 99, and 90% levels of the observed sea level have been calculated at all 15 tide gauges (Figure 3)
Results show that the three percentile levels of extreme sea level all rose with fluctuations at most tide gauges except at QHD, SW, and BH

Summary

Introduction

China has the largest coastal population in the world, with more than 40% people living in the coastal area, where the extreme sea level disasters occur frequently and have caused serious negative impacts. According to the China Marine Disaster Bulletin, the extreme sea level incidents have caused economic losses of 11.1 billion (RMB) and 49 deaths annually between 2000 and 2017. Increases in the mean and extreme sea levels are regarded as one of the consequences of climate change (Church et al, 2013). Many studies have been done about the changes of extreme sea levels both regionally and globally (von Storch and Reichardt, 1997; Woodworth and Blackman, 2004; Méndez et al, 2007; Menéndez and Woodworth, 2010; Feng et al, 2015; Marcos and Woodworth, 2017).

Methods

Results

Conclusion