This paper focuses on the analysis of carbonyl sulfide (OCS) measurements obtained from ground-based Fourier transform spectrometer (FTS) instruments at three Southern Hemisphere sites spanning 34.45°S to 77.80°S. At all three sites statistically significant positive trends are seen from 2001 to 2014 with an observed overall trend in total column OCS at Wollongong of 0.73 ± 0.03%/yr, at Lauder of 0.43 ± 0.02%/yr, and at Arrival Heights of 0.45± 0.05%/yr. These observed trends in OCS imply that the OCS budget is not balanced and therefore provides new constraints on current estimates of sources and sinks. 

This research was supported by the Royal Society of New Zealand through the Marsden Fast-Start Fund.