Exposure analysis of Chinese railways under the Change of Extreme-Precipitation in the future

Abstract: Rainfall-induced disaster is the most frequent disaster affected Chinese Railway System. Climate change will lead to more extreme rainfall in the future. A better understanding of extreme precipitation in the future and the exposure of railway infrastructures to extreme precipitation will facilitate railway planning and disaster risk management. This paper employs climate model simulations to calculate the changes of the extreme precipitation under different global warming scenarios. The return periods of the present 50-yr/100-yr return-period precipitation amount in the future are obtained. Based on this, the changes of the exposure of Chinese railways to extreme precipitation are analyzed. The results reveal that 58.61% (55.46) of China’s region will experience an increase in the 50-yr(100-yr) return-period precipitation under 1.5°C warming in comparison with the present period (2001–2020), the value will be 64.44% and 59.53% due to the additional 0.5°C warming. By calculating the exposure of Chinese railways, we found that 28.49% (32.15) of China's railways are in the region where 50-yr return-period rainfall at this stage will occur less than 20 years under 1.5°C (2.0°C) warming, and 36.85% (41.39)of China's railways are in the region where 100-yr return-period rainfall at this stage will occur less than 50 years under 1.5°C (2.0°C) warming in the future. This study quantified the exposure of China’s railway to extreme precipitation under the 1.5°C/2.0°C global warming. The results provided in this study have profound significance for the fortification planning of China's railway system for rainfall-induced disasters and provide useful experience for other countries.