Long-Term Monitoring and Correction of FY-2 Infrared Channel Calibration Using AIRS and IASI

作者：Hu, Xiuqing^*; Xu, Na; Weng, Fuzhong; Zhang, Yong; Chen, Lin; Zhang, Peng

来源：IEEE Transactions on Geoscience and Remote Sensing, 2013, 51(10): 5008-5018.

DOI：10.1109/TGRS.2013.2275871

• Calibration
• double-difference temperature (DDT)
• FengYun (FY) satellite
• global space-based intercalibration system (GSICS)

Hyperspectral radiances from the Infrared Atmospheric Sounding Interferometer (IASI) and Atmospheric Infrared Sounder (AIRS) are used as a reference to improve the calibration accuracy for FengYun-2 (FY-2) infrared (IR) channel radiances. It is shown that the previous FY-2 operational calibration for IR bands produces significant bias in brightness temperatures that can exceed 1.1 K. In particular, the FY-2 IR3 band (6.7 mu m) has the largest bias of 2.0 K. The daytime double-difference temperature (DDT) between AIRS and IASI using FY-2 imagers as a transfer medium showed an excellent consistency, is within 0.2 K at 290 K, and is stable over time for FY-2C/2D/2E. This only indicates the robust calibrations applied for both the AIRS and IASI measurements. During the nighttime of the Earth observation, stray light in space affects the long-term stability of the FY-2 DDT, particularly for the Earth scene at 220 K. FY-2E satellite which was launched in 2009 has an instrument design improvement. Intercalibrating FY-2 four times using AIRS and IASI data can reveal the diurnal features of the FY-2 instrument calibration. The temporal DDT appears very large during the spring and autumn eclipse times. Not only can the global-space-based-intercalibration-system intercalibration method provide an excellent operational calibration for the FY-2 imager, but it can also help improve the design of future instruments and onboard blackbody calibration.

• 出版日期2013-10