陆地垂向运动对沿海相对海平面变化的影响  

Influence of Land Vertical Motion on Coastal Relative Sea Level Change

作　　者：谢书谊 陈美香[1] 张建立[2] 肖凯 XIE Shu-yi;CHEN Mei-xiang;ZHANG Jian-li;XIAO Kai(College of Oceanography, Hohai University , Nanjing 210098, China;National Marine Information Center, Tianjin 300171, China)

机构地区：[1]河海大学海洋学院,江苏南京210098 [2]国家海洋信息中心,天津300171

出　　处：《海洋科学进展》2019年第2期187-198,共12页Advances in Marine Science

基　　金：国家自然科学基金项目--风对热带太平洋海平面低频变化影响机制的数值模拟研究(41506006)和热带太平洋年代际变化机制研究(41576020);国家重点研发计划项目--海洋-海冰参量和物理过程的观测数据集构建与模式评估(2017YFA0604602);全球变化与海气相互作用专项课题--海洋中尺度过程与台风的相互作用(GASI-IPOVAI-04)

摘　　要：沿岸陆地垂向运动是沿海相对海平面变化的重要组成部分,可以通过GPS直接观测或者联合验潮站和高度计资料进行推算,前者较为精确但目前欠发达国家和地区沿岸数据缺乏,后者资料相对丰富但准确性有待验证。本研究利用全球191个验潮站数据及同步的高度计资料和GPS监测数据,对两种方法得到的陆地垂向运动速率进行了比较,发现对于陆地垂向运动明显的站位,两种方法计算的趋势相同比例为74%;陆地垂向运动速率的空间分布表现为高纬度沿岸陆地抬升和中低纬度不同程度的陆地沉降,这与冰川均衡调整(GIA)模型结果和近期GRACE重力卫星观测较为符合,说明了基于验潮站和高度计联合推算沿岸陆地垂向运动的方法具有较高可行性。将此方法应用于中国沿岸,基于29个长期验潮站数据计算了中国沿海1993—2016年陆地垂向运动速率,发现存在以长江口为分界北升南降的空间特征;南部沿岸陆地沉降会加剧沿海相对海平面上升,给区域经济发展和人民生活带来风险。The vertical land motion is a very important component in coastal sea level change observed by tide gauges and it can be either observed directly with GPS or deduced from the data of tide gauges and satellite altimeters.GPS is more accurate but observations of GPS in less developed countries and regions are limited at present;the data of tide gauges and satellite altimeters are relatively abundant, but their accuracy needs to be verified.In this paper, we calculated the velocity of vertical land motion at 191 tide gauges over the globe using the observation data from both GPS and tide gauge as well as satellite altimeter.The results show that for the stations with obvious vertical land motion, the ratio of the two methods showing the same trend is 74%.The spatial distribution of the vertical motion rate of the land is characterized by land uplift at high latitudes and land subsidence at low and medium latitudes.This finding is well consistent with the result of glacial isostatic adjustment model (GIA) and GRACE gravity satellite data.The method of using tide gauge and altimeter data to calculate the vertical land motion velocity is applied to the observations from 1993-2006 obtained at 29 long-term tide gauges along the coast of China.Results show that coastal areas to the north of the Yangtze River estuary show an uplifting trend while those to the south show a subsiding trend.Land subsidence will increase the rise of relative sea level, posing great risks to local economy and community.

关 键 词：陆地垂向运动 验潮站 高度计 GPS 

分 类 号：P714.1[天文地球—海洋科学]