论文部分内容阅读
20世纪90年代以来,卫星高度计在监测海平面变化、海洋环流、区域海面地形、气候变化等方面做出了巨大的贡献。但是,卫星高度计测量海面高度时都会存在偏差和偏移,需要进行定标。定标的基本原理是在卫星星下点位置处,卫星过境时刻现场测量海面绝对高度值,与卫星高度计的测量值进行对比,得到其偏差和偏移。利用自主设计的GPS浮标测量卫星过境时刻的瞬时绝对海面高度值,分别在山东石岛、海南清澜完成了4次针对HY-2卫星高度计的绝对定标工作。定标结果表明:(1)在岸基GPS基准站的支持下,使用自制的GPS浮标海面高程测量精度优于50mm,满足高度计定标检验的需求;(2)HY-2卫星高度计测量的海面高度测量值随时间产生了漂移,存在系统偏差;(3)通过使用Jason-2高度计数据对HY-2的相对定标和使用GPS浮标对其进行的绝对定标结果表明,HY-2绝对海面高度测量的精度可以达到国际先进水平。
Since the 1990s, satellite altimeters have made great contributions in monitoring sea level changes, ocean circulation, regional sea topography and climate change. However, satellite altimeters have deviations and shifts in sea level measurements that require calibration. The basic principle of calibration is to measure the absolute height of the sea surface at the satellite under the satellite spot, and to compare with the measured value of the satellite altimeter to get the deviation and offset. Using the self-designed GPS buoy to measure the instantaneous absolute sea surface height at the satellite transit time, the absolute calibration for the HY-2 satellite altimeter has been completed in Shidao, Shandong and Qinglan, Hainan respectively. The calibration results show that: (1) The accuracy of sea surface elevation measurement using self-made GPS buoy is better than 50mm, which is supported by shore-based GPS base stations; (2) The sea surface measured by HY-2 satellite altimeter (3) The relative calibration of HY-2 using the Jason-2 altimetry data and its absolute calibration using GPS buoys show that the HY-2 absolute sea surface The accuracy of the height measurement can reach the international advanced level.