The impact of chlorofluorocarbon (CFC) release on the earth's ozone shield is becoming more evident with every passing year. It is imperative that the long term continuous monitoring of this environmental global experiment proceeds by every means possible. The National Oceanic and Atmospheric Administration (NOAA) has 14 years of TIROS Operational Vertical Sounder (TOVS) earth radiation data that includes ozone sensitive 9.7 micrometer information. The current 14 year sequence of daily TOVS ozone maps from February 1979 to May 1993 covers a period of unprecedented decline of the earth's ozone shield. Recent Antarctic ozone holes are developing earlier, growing larger and lasting longer than ever before. While there is no evidence as yet of persistent Arctic `sub-250 Dobson Unit' ozone values, the robust Arctic spring ozone peaks of earlier decades have shrunk by a third. Worst of all, 1993 Northern mid-latitude TOVS ozone values dropped to levels 11% below normal. TOVS ozone data is essential for understanding the recent polar ozone declines and their relationship to ozone declines in populous temperate zone regions.
"Decline in polar stratospheric ozone as observed by NOAA infrared sounders", Proc. SPIE 2047, Atmospheric Ozone, (2 November 1993); doi: 10.1117/12.163472; https://doi.org/10.1117/12.163472