CALIBRATION OF CCL2FCCLF2 (CFC-113) AND ITS EFFECTS ON THE ATMOSPHERIC LONG-TERM MEASUREMENTS

A simple but innovated calibration procedure for the measurements of v olatile organic compounds in the atmosphere is, introduced via the use of CCl2FCCIF2 (CFC-113) long-term global data set as an illustration. Non-linear response for the electron capture detector toward CFC-113 was carefully calibrated within and beyond the measurement working ran ge. Our measurement results, after correction for non-linearity, are i n excellent agreement with those of the ALE/GAGE monitoring program, s uggesting our calibration method along with its results are experiment ally sound and well executed. Our global measurements show that, after years of rapid growth of CFC-113 in the atmosphere, its concentration had been leveling-off and even started to decline in 1995.