Southern hemisphere ground based measurements of carbonyl fluoride (COF₂) and hydrogen fluoride (HF): Partitioning between fluoride reservoir species

Abstract

We report infrared ground based total column measurements of the stratospheric fluorine reservoir gases COF2 and HF above Lauder, New Zealand (45°S, 167.8°E) obtained between April 1993 and January 1994. The average retrieved COF2 and HF total columns are 2.81(±0.56)×1014 and 9.91(±1.09)×1014 molecules/cm², respectively. The daily average COF2 and HF columns are correlated; this correlation is likely the result of dynamics. The average HF/COF2 column ratio on days with measurements of both HF and COF2 is 3.63 (±0.55). Comparison of this ratio with model calculations implies that the quantum yield for COF2 photolysis is near unity. Our measured COF2 columns are higher than all previously reported values, but inconsistencies among the earlier measurements and uncertainty in the latitudinal gradient of the COF2 column preclude an accurate determination of the long‐term COF2 trend. Show more