中国近海海平面变化趋势的对比分析

本文分析了近40年的中国近海验潮站资料海表面高度的线性变化趋势,并与卫星高度计资料进行了对比。通过对验潮站资料的分析发现,中国海域无论是近40年(1970~2013年)、还是近20年(1993~2013年)海平面均显著上升。各海区近20年的海平面上升有加速的趋势,且各时段上升速率大于全球平均海平面上升率。但是,受到海平面的年际和年代际变化的影响,近10年海平面上升趋势放缓。同时,本文也分析了不同季节海平面变化的趋势,北部海域秋季最大,冬季最小;南海海域春季最大,秋季最小。通过AVISO资料和验潮站资料的对比可以发现,AVISO资料在描述近20年海平面变化的线性趋势上与验潮站资料接近,较大的差异主要是由验潮站地表发生升降引起的。同时,通过对比也发现了用验潮站资料估算海域平均的海平面高度变化会有一定的误差,在黄海、渤海、东海海域验潮站估计的数值偏高,而在南海海域则偏低。

Analysis and Comparison of the Sea Level Rising Trend in the Marginal Seas around China

The linear trend in sea level rise (SLR) in recent 40 years in the marginal seas around China is analyzed by using the tide gauge (TG) data. Results are compared with satellite remote sensing data. Results from the TG data indicate that the sea level height around the China has been significantly rising in both the recent 40 years and the recent 20 years. The trends in SLR in all the study regions have accelerated in the recent 20 years. Furthermore, the speed of SLR is greater than the global averaged SLR in all the study periods. However, the trend in SLR during the recent 10 years has slowed down due to the interannual and interdecadal variability in sea level height. In addition, the trends in SLR in different seasons are also investigated. A comparison between the AVISO data and TG data indicates that the linear trend during the recent 20 years can be well reproduced by AVISO data. Large differences are mainly caused by the rise of the land surface. Meanwhile, it is also found that there are biases if we use samples such as data collected at tidal gauge stations to estimate the trend of the mean SLR, which is overestimated in the Bo-Yellow-East Sea (BYE) and underestimated in the South China Sea (SCS).