卫星红外载荷辐射定标是定量化应用的重要前提，选择合适的辐射定标参考是实现卫星传感器高频次、高精度定标，进而维持全生命周期观测稳定性的保障。再分析资料能够提供全球覆盖、一定空间和时间分辨率的地表及大气数据，已在气候应用中展现了重要价值，其作为辐射定标参考的适用性值得研究。本文以欧洲中期天气预报中心ERA5再分析资料为研究对象，首先利用Argo浮标观测海表温度（SST）和Terra-MODIS L2级SST日产品，对ERA5数据集的海洋表皮温度参数（SSTskin）进行验证；其次利用MODIS观测星上亮温值，对使用ERA5 SSTskin和大气廓线数据模拟得到星上亮温值进行验证。结果表明，ERA5 SSTskin与Argo SST的平均偏差在-0.31K以内，与MODIS SST产品的平均偏差在-0.38K以内，且与Argo SST的偏差在时间和空间上更为稳定；辐射传输计算结果显示，与星上观测亮温的平均偏差也在-0.38K以内，且偏差随时间和纬度变化波动较小。最后，本文还探究了风速、大气水汽柱总量、海浪平均高度等气象影响因素与海表温度偏差和星上亮温偏差的相关性，整体看来，在6~16 m/s中等风速，低于7.0 g/cm2水汽柱总量以及0.6~3m海浪平均高度的条件下，海表温度偏差以及星上亮温偏差较低。研究结果可为再分析资料用于不依赖实测数据的卫星红外载荷绝对辐射定标提供有效支撑。

Thermal infrared radiometric calibration of satellite sensors is an important prerequisite for the quantitative remote sensing. Appropriate radiometric calibration source is the guarantee of high-frequency and high-precision calibration for a satellite sensor , as well as the guarantee of observation stability during the on-orbit stage. The re-analysis data provides the worldwide surface and atmospheric data with fixed resolution, which has been of great value in climate applications. The feasibility of re-analysis data as a reference source for radiometric calibration is worthy of being studied. In this paper, the ERA5 re-analysis data of the European Center for Medium-Range Weather Forecasting was used. Argo buoy sea surface temperature (SST) and Terra-MODIS L2 SST daily products were used to verify the sea surface skin temperature (SSTskin) of ERA5. The MODIS observed brightness temperature (BT) was used to verify the top of atmosphere (TOA) simulation with the support of ERA5 SSTskin and atmospheric profile data. The results show that the mean bias error (MBE) between the ERA5 SSTskin and Argo SST is -0.31 K, the MBE between the ERA5 SSTskin and MODIS SST is -0.38 K. And the former temperature difference shows more stable than the latter one. The RMSE between the simulated TOA brightness temperatures and MODIS observations is also -0.38 K. Subsequently, some meteorological factors, such as wind speed, total column water vapor, and ocean wave height, were used to analyze the correlation with the differences of SSTskin and TOA brightness temperature. Overall, in the conditions of medium wind speed of 6-16 m/s, total column water vapor of less than 7.0 g/cm2, and ocean wave height of 0.6-3 m, the differences of SSTskin and TOA brightness temperature is relatively lower. The results can provide the accurate basis for re-analysis data as a reference source thermal infrared radiometric calibration.