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

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.