1993—2018年中国沿海海平面异常升高的时空格局特征及潜在社会经济风险估计

全球变暖诱发海平面上升是当前陆海作用领域的热点议题。应用卫星高度计观测海平面异常（SLA）数据,结合共享社会经济路径情景（SSP_S）,探讨我国沿海地区1993—2018年海平面异常升高的时空格局特征及潜在社会经济风险。结果显示：（1）过去26年间,我国沿海年均海平面和极端海平面均呈波动上升趋势,变化速率分别达到3.47±0.50 mm/a和4.74±1.39 mm/a。（2）空间上,我国四大海区上升速率由高到低排序为：东海>黄海>渤海>南海;省域尺度上,苏、闽、浙的海平面增速较大,而粤、沪、台的海平面上升速率较慢。（3）MK检验和Sen趋势分析显示,整个海区的年均海平面全部呈显著增加趋势,其中84.16%的区域处于增速中等偏慢水平,2.32%的区域增速快;而极端海平面中显著增加区域占76%,其中59.65%的区域增速慢,2.31%的区域增速快;无显著减少区域。（4）空间波动性上,我国历年海平面变化整体处于较低的波动水平;其中,较低波动区占61.31%,而高波动与较高波动区仅占到3.17%。（5）到2100年,我国海平面上升高度将达到71.71±19.01 cm;在三种共享社会经济发展路径下（SSP₁、SSP₂和SSP₃）,我国沿海地区潜在经济损失将达10万~21万亿元人民币（2005年可比价）,受影响人口数达350万~550万人;其中,广东省水淹面积最大（占到省份陆域总面积的0.7%）,经济和人口风险也最高。因此,减缓和应对海平面上升风险,是21世纪我国沿海地区保持经济社会、资源环境可持续发展的重要命题。

Assessment of spatio-temporal distribution characteristic of sea level anomaly changes and its potential socio-economic risks in China's coastal areas from 1993 to 2018

Global warming induced sea level rise is a hot topic in the field of land-sea interaction. Coastal erosion and flooding caused by sea level rise pose a great threat to the environment and economic development. We examined the spatial-temporal distribution characteristics and potential social and economic risks of sea level change in China's coastal areas from 1993 to 2018 based on the sea-level anomaly (SLA) data and the shared social and economic path scenario (SSP_S). The results showed that: (1) During the study period, the average annual sea level and extreme sea level in the study area showed a significant rising trend, with the rate of change reaching up to 3.47±0.50 mm/a and 4.74±1.39 mm/a, respectively. (2) The rising rate of the four major sea areas of China is listed is as follows: East China Sea > Yellow Sea > Bohai Sea > South China Sea. In terms of the provincial scale, Jiangsu, Fujian and Zhejiang have higher sea level growth rates, while Guangdong, Shanghai and Taiwan have lower sea level rise rates. (3) The results of MK test and Sen trend analysis showed that the average annual sea level had a significant increase trend in the whole study area. Specifically, 84.16% of the area had a moderately slow growth rate and 2.32% of the area was going fast. As for the extreme sea level, areas with a significant increase accounted for 76%, of which 59.65% had a slow growth and 2.31% had a fast growth. During the study period, there was no significant reduction in the area. (4) In terms of spatial volatility, the sea level change over the past decades had been at a relatively low volatility level. According to statistical results, the lower volatility area accounts for 61.31%, while the highest and higher volatility areas only account for 3.17%. (5) By 2100, under three shared social and economic development paths (SSP₁, SSP₂ and SSP₃), the potential economic losses in Chinese coastal areas will reach 10-21 trillion yuan, and the population affected by sea level rise is about 3.5-5.5 million. From the provincial perspective, Guangdong has the largest flooded area (accounting for 0.7% of the total land area of the province), and the highest economic and population risks. Therefore, mitigation and adaption to the risk of sea level rise is an important task for maintaining sustainable socio-economic development, resources utilization and environmental protection in China's coastal areas in the 21st century.