The Yangtze River Delta characterized by a dense population and a rapidly developing economy is highly vulnerable to sea-level rise. The data from the China Oceanic Information Network and the Zhejiang Provincial Hydr...The Yangtze River Delta characterized by a dense population and a rapidly developing economy is highly vulnerable to sea-level rise. The data from the China Oceanic Information Network and the Zhejiang Provincial Hydrology Bureau are used to analyze sea-level rise. The rate of sea-level rise in the delta was 2.4 mm per year in 1981-2015. The annual sea-level at Daishan, Dinghai, and Dongtou stations in the south wing of the delta were 4.3, 3.1, and 5 mm per year respectively over the same period. The 10-year averaged results at each station also indicate a perceptible trend of sea-level rise. Sea-level rise is contributed to a larger proportion of intensified erosion, ranging from 3% to 14% in the delta. Meanwhile, the 100-year return period of tidal level has decreased to the 50-year rank at Dongtou and Dinghai stations. Moreover, the arrival time of tidal bores at Yanguan is 4 min earlier under sea-level rise of 0.145 m than that of 0 m. The height of tidal bores and the velocities at the surface and bottom layers have an increase under sea-level rise. The maximum increases of high and low tide levels are 0.122 m and 0.016 m while the maximum increases of the velocities at the surface and bottom layers are 0.07 m s^- 1 and 0.05 m s ^-1, respectively. Sea-level rise will bring about the damage of seawall, thus the design standard of constructing seawalls should adopt a higher level to minimize the associated risks in the Yangtze River Delta and its south wing.展开更多
基金This work was supported by the projects of National Science Foundation of China (41706099, 51779228, 51379190, 41676085), and the Science and Technology Plans of Zhejiang province (2015F50011, 2016F50017). The authors acknowledged the anonymous reviewers' comments to improve this paper.
文摘The Yangtze River Delta characterized by a dense population and a rapidly developing economy is highly vulnerable to sea-level rise. The data from the China Oceanic Information Network and the Zhejiang Provincial Hydrology Bureau are used to analyze sea-level rise. The rate of sea-level rise in the delta was 2.4 mm per year in 1981-2015. The annual sea-level at Daishan, Dinghai, and Dongtou stations in the south wing of the delta were 4.3, 3.1, and 5 mm per year respectively over the same period. The 10-year averaged results at each station also indicate a perceptible trend of sea-level rise. Sea-level rise is contributed to a larger proportion of intensified erosion, ranging from 3% to 14% in the delta. Meanwhile, the 100-year return period of tidal level has decreased to the 50-year rank at Dongtou and Dinghai stations. Moreover, the arrival time of tidal bores at Yanguan is 4 min earlier under sea-level rise of 0.145 m than that of 0 m. The height of tidal bores and the velocities at the surface and bottom layers have an increase under sea-level rise. The maximum increases of high and low tide levels are 0.122 m and 0.016 m while the maximum increases of the velocities at the surface and bottom layers are 0.07 m s^- 1 and 0.05 m s ^-1, respectively. Sea-level rise will bring about the damage of seawall, thus the design standard of constructing seawalls should adopt a higher level to minimize the associated risks in the Yangtze River Delta and its south wing.