摘要: |
应用TOPEX/POSEIDON(T/P)卫星高度计测高资料,对全球海洋的海面变化特征进行了分析,结果表明,1993年1月—2001年6月期间,全球海平面呈现上升的态势;全球平均海平面高度的平均上升速率约为1.2mm/a;海温的变化是引起海平面变化的重要原因,但其对海平面抬升的贡献不到50%。海平面的变化具有很强的地域特征。海平面变化的空间分布特征受风应力异常特别是纬向风应力异常的空间分布影响较大。
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关键词: 平均海平面,海面抬升,T/P卫星高度计 |
DOI:10.11693/hyhz200302007007 |
分类号: |
基金项目:国家高科技发展计划项目,863-818-01-02号和2002AA639480号 |
附件 |
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SEA SURFACE LEVEL VARIATIONS DURING 1993—2001 |
SHEN Hui, GUO Pei-Fang, QIAN Cheng-Chun, HAN Shu-Zong
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Ocean University of China
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Abstract: |
Variations of global mean sea level (GMSL) are an important indicator of global climate change. It is believed that sea level rise is a proof of global warming. Usually, the research is done by analyzing data of tide gauge, which has a limitation for its poor spatial resolution and spatial coverage. The development of remote sensing has provided us with a new way to study GMSL variation using altimeter data, which can overcome the limitation of tide gauge data and has its own advantages. In this paper, we use data of TOPEX/POSEIDON altimeter to study SSL variations during 1993.01—2001.06. Global mean sea level in this period shows clearly a trend of rise with a velocity of +1.2 mm/a. Annual variations are the most dominant signal in 10-day-averaged sea level time series. Compared to the south hemisphere, the north hemisphere has a larger magnitude of annual variation because of its relatively small ocean coverage. In order to identify the mechanism of sea level rise, the variations in global mean sea temperature are also analyzed. There is a good relationship between global mean sea level variation and global mean sea temperature, with a correlation coefficient of 0.54. The variation of global mean sea level also shows a remarked annual signal, which can be used to explain
the annual variation of global mean sea level. A simple statistical model is established, which shows that the contribution
of thermal expansion during 1993.01—1999.12 is not more than 50%. The variation of sea level rise also shows strongly a geographical distribution, in response to the spatial distribution of the anomaly of wind speeds.
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Key words: Mean sea level rise, T/P Altimeter, Global warming |