Southern hemisphere ground based measurements of carbonyl fluoride (COF 2 ) and hydrogen fluoride (HF): Partitioning between fluoride reservoir species

We report infrared ground based total column measurements of the stratospheric fluorine reservoir gases COF 2 and HF above Lauder, New Zealand (45°S, 167.8°E) obtained between April 1993 and January 1994. The average retrieved COF 2 and HF total columns are 2.81(±0.56)×10 14 and 9.91(±1.09)×10 14 molecules/cm², respectively. The daily average COF 2 and HF columns are correlated; this correlation is likely the result of dynamics. The average HF/COF 2 column ratio on days with measurements of both HF and COF 2 is 3.63 (±0.55). Comparison of this ratio with model calculations implies that the quantum yield for COF 2 photolysis is near unity. Our measured COF 2 columns are higher than all previously reported values, but inconsistencies among the earlier measurements and uncertainty in the latitudinal gradient of the COF 2 column preclude an accurate determination of the long‐term COF 2 trend.