Application of the SKYRAD Improved Langley （应用SKYRAD兰利的改善）.pdfVIP

Application of the SKYRAD Improved Langley plot method for the in situ calibration of CIMEL Sun–sky photometers Monica Campanelli, Víctor Estellés, Claudio Tomasi, Teruyuki Nakajima, Vincenzo Malvestuto, and José Antonio Martínez-Lozano The in situ procedure for determining the solar calibration constants, originally developed for the PREDE Sun–sky radiometers and based on a modified version of the Langley plot, was applied to a CIMEL instrument located in Valencia, Spain, not integrated into AERONET. Taking into account the different mechanical and electronic characteristics of the two radiometers, the method was adapted to the char- acteristics of the CIMEL instrument. The iterative procedure for the determination of the solar cali- bration constants was applied to a 3-year data set. The results were compared with the two sets of experimental calibration constants determined during this period using the standard Langley plot method. The agreement was found to be consistent with the experimental errors, and the method can definitely also be used to determine the solar calibration constant for the CIMEL instrument, improving its calibration. The method can be used provided the radiometer is previously calibrated for diffuse radiance using a standard lamp. © 2007 Optical Society of America OCIS codes: 010.1290, 010.1110. 1. Introduction techniques. Two of these networks are the SKYNET Atmospheric aerosols have an important effect on the net