摘要
本文以同期观测的Jason-2地球物理数据GDR为参考,对海洋二号(HY-2A)雷达高度计临时地球物理数据IGDR的主要测高参数与交叉点测高不符值做了评价分析,对研究发现的HY-2A测高数据质量问题给出了总结和改进建议.研究发现HY-2A存在明显的整轨迹数据丢失现象,且数据编辑比例偏高,导致测高数据的可用性相对较差.HY-2A与Jason-2的有效波高差异均值为-3.8 cm±7.1 cm,具有较高观测精度.但研究发现HY-2A后向散射系数存在异常跳变与漂移现象,电离层延迟的模型改正值与双频观测改正值的相关性为0.095,可靠性较差.HY-2A海面高异常与Jason-2比较存在速率约-60.9 cm/y的漂移,与星上超稳振荡漂移有关.交叉点分析表明HY-2A交叉点海面高不符值的标准差为6.52 cm,与Jason-2精度偏差在1 cm左右,满足海洋科学研究和应用的要求.
In this paper, the quality and accuracy of HY-2A Interim Geophysical Data Record( IGDR) of the latest version were assessed through the comparison with the Jason-2 GDR data measured at the same time. The main parameters of the HY-2A altimeter were analyzed. The differences of sea surface height( SSH) at crossover points of HY-2 and Jason-2 were calculated.We found that the passes of HY-2A were lost significantly in some circles causing the low coverage rate of ocean data. The editing proportion of HY-2A is higher than Jason-2 which could cause the poor usability of the altimetry data. The mean difference of significant wave height between HY-2A and Jason-2 is- 3. 8 cm ±7. 1 cm which demonstrates the close accordance between two satellites. However,the backscatter coefficient shows the abnormal leap. The Sea State Bias( SSB) difference of HY-2A and Jason-2 is as high as- 3. 3 cm ± 0. 3 cm. The ionosphere model value of HY-2A IGDR is inaccurate because the correlation coefficient of the model ionosphere value with the dual-frequency ionosphere value is0. 095 which is extremely weak. In addition,we found that the HY-2A sea level anomaly shows a significant drift of- 60. 9 cm / y which may relate to the Ultra Stable Oscillator( USO). The crossover points analysis indicates that the standard deviation( STD) of the SSH crossover difference is 6. 52 cm,which is higher than Jason-2 about 1cm and meet requirements of the oceanic scientific research and application.
出处
《地球物理学进展》
CSCD
北大核心
2016年第2期629-636,共8页
Progress in Geophysics
基金
国家海洋局第一海洋研究所基本科研业务费专项资金项目(GY0214G23)
国家国际科技合作专项(2014DFA21710)
中央级公益性科研院所基本科研业务费专项资金资助项目(GY02-2011T05)联合资助