The first Chinese microwave ocean environment satellite HY-2A, carrying a Ku-band scatteromenter (SCAT), was successfully launched in August 2011. The first quality assessment of HY-2A SCAT wind products is presente...The first Chinese microwave ocean environment satellite HY-2A, carrying a Ku-band scatteromenter (SCAT), was successfully launched in August 2011. The first quality assessment of HY-2A SCAT wind products is presented through the comparison of the first 6 months operationally released SCAT products with in situ data. The in situ winds from the National Data Buoy Center (NDBC) buoys, R/V Polarstern, Aurora Australis, Roger Revelle and PY30-1 oil platform, were converted to the 10 m equivalent neutral winds. The temporal and spatial differences between the HY-2A SCAT and the in situ observations were limited to less than 5 min and 12.5 km. For HY-2A SCAT wind speed products, the comparison and analysis using the NDBC buoys yield a bias of-0.49 m/s, a root mean square error (RMSE) of 1.3 m/s and an increase negative bias with increasing wind speed observation above 3 m/s. Although less accurate of HY-2A SCAT wind direction at low winds, the RMSE of 19.19° with a bias of 0.92° is found for wind speeds higher than 3 m/s. These results are found consistent with those from R/Vs and oil platform comparisons. Moreover, the NDBC buoy comparison results also suggest that the accuracy of HY-2A SCAT winds is consistent over the first half year of 2012. The encouraging assessment results over the first 6 months show that wind products from HY-2A SCAT will be useful for scientific community.展开更多
The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height (SWH) is validated by the data from the South China Sea (SCS) field experiment, National Data Buoy Center (NDBC/ bu...The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height (SWH) is validated by the data from the South China Sea (SCS) field experiment, National Data Buoy Center (NDBC/ buoys and Jason-1/2 altimeters, and is corrected using a linear regression with in-situ measurements. Com- pared with NDBC SWH, the HY-2 SWH show a RMS of 0.36 m, which is similar to Jason- 1 and Jason-2 SWH with the RMS of 0.35 m and 0.37 m respectively; the RMS of corrected HY-2 SWH is 0.27 m, similar to 0.27 m and 0.23 m of corrected Jason-1 and Jason-2 SWH. Therefore the accuracy of HY-2 SWH products is close to that of Jason-1/2 SWH, and the linear regression function derived can improve the accuracy of HY-2 SWH products.展开更多
海洋二号D卫星(HY-2D)是中国第4颗海洋动力环境卫星,为研究HY-2D卫星的多普勒无线电定轨定位系统DORIS(Doppler Orbitography and Radio-positioning Integrated by Satellite)的定轨精度,本文构建了卫星姿态模型,选择2021年6月5—17日D...海洋二号D卫星(HY-2D)是中国第4颗海洋动力环境卫星,为研究HY-2D卫星的多普勒无线电定轨定位系统DORIS(Doppler Orbitography and Radio-positioning Integrated by Satellite)的定轨精度,本文构建了卫星姿态模型,选择2021年6月5—17日DORIS相位测量数据,采用观测值历元间差分和动力学方法进行精密定轨,对定轨结果通过观测值拟合残差、重叠弧段、轨道相互比较和激光检核4种方法评估轨道精度,并对使用姿态模型或姿态数据的2种定轨结果之间差异进行讨论。结果表明:(1)13 d观测值残差RMS均值约为0.355 mm/s,轨道重叠弧段三维差异的RMS<2.0 cm;(2)与法国国家空间研究中心CNES(Centre National D’Etudes Spatiales)的精密轨道相比,使用姿态数据两者在径向R、切向T、法向N方向上差异的均方根误差RMS(Root Mean Square)分别为1.02 cm、2.92 cm和3.11 cm,使用姿态模型两者在径向R、切向T、法向N方向上差异的RMS分别为0.97 cm、2.77 cm和3.15 cm。2种结果接近,表明卫星姿态模型与实测姿态数据符合程度高;(3)用激光检核本文计算的轨道与CNES参考轨道的精度,测距残差的RMS分别为2.38 cm和2.24 cm,两种轨道精度相当。展开更多
基金The Marine Public Welfare Project of China under contract No.201105032the National High-Tech Project of China under contract No.2008AA09A403the fund of State Administration for Science,Technology and Industry for National Defense
文摘The first Chinese microwave ocean environment satellite HY-2A, carrying a Ku-band scatteromenter (SCAT), was successfully launched in August 2011. The first quality assessment of HY-2A SCAT wind products is presented through the comparison of the first 6 months operationally released SCAT products with in situ data. The in situ winds from the National Data Buoy Center (NDBC) buoys, R/V Polarstern, Aurora Australis, Roger Revelle and PY30-1 oil platform, were converted to the 10 m equivalent neutral winds. The temporal and spatial differences between the HY-2A SCAT and the in situ observations were limited to less than 5 min and 12.5 km. For HY-2A SCAT wind speed products, the comparison and analysis using the NDBC buoys yield a bias of-0.49 m/s, a root mean square error (RMSE) of 1.3 m/s and an increase negative bias with increasing wind speed observation above 3 m/s. Although less accurate of HY-2A SCAT wind direction at low winds, the RMSE of 19.19° with a bias of 0.92° is found for wind speeds higher than 3 m/s. These results are found consistent with those from R/Vs and oil platform comparisons. Moreover, the NDBC buoy comparison results also suggest that the accuracy of HY-2A SCAT winds is consistent over the first half year of 2012. The encouraging assessment results over the first 6 months show that wind products from HY-2A SCAT will be useful for scientific community.
基金The Marine Public Welfare Project of China under contract No.201105032the National High-Tech Project of China undercontract No.2008AA09A403the fund of State Administration for Science,Technology and Industry for National Defense
文摘The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height (SWH) is validated by the data from the South China Sea (SCS) field experiment, National Data Buoy Center (NDBC/ buoys and Jason-1/2 altimeters, and is corrected using a linear regression with in-situ measurements. Com- pared with NDBC SWH, the HY-2 SWH show a RMS of 0.36 m, which is similar to Jason- 1 and Jason-2 SWH with the RMS of 0.35 m and 0.37 m respectively; the RMS of corrected HY-2 SWH is 0.27 m, similar to 0.27 m and 0.23 m of corrected Jason-1 and Jason-2 SWH. Therefore the accuracy of HY-2 SWH products is close to that of Jason-1/2 SWH, and the linear regression function derived can improve the accuracy of HY-2 SWH products.