Monitoring Ozone Depletion
Monitoring of the ozone layer has increased significantly since the 1980s when the Antarctic ozone hole was first discovered by the British Antarctic Survey. The ozone layer is monitored both by satellites and ground-based resources that are dedicated to observing the destruction of stratospheric ozone.
The main satellite that monitors the ozone layer is the TOMS (Total Ozone Mapping Spectrometer) satellite. The TOMS satellite measures the ozone levels from the back-scattered sunlight in the ultraviolet (UV) range. Another satellite is NASA's UARS (Upper Atmosphere Research Satellite) which was launched in September 1991. This satellite is unique because it was configured to not only measure ozone levels, but also levels of ozone-depleting chemicals. GOME, launched in April 1995 on the ERS-2 satellite, marked the beginning of a long-term European ozone monitoring effort. Scientists receive high quality data on the global distribution of ozone and several other climate-influencing trace gases in the Earth's atmosphere.
In 1987, Canada became the first country in the world to focus on the Arctic ozone layer, following the discovery of the ozone hole over the Antarctic. A cross-country network of monitoring stations has kept continuous watch on Canada’s ozone layer for more than three decades. The existence of these early records, before any major human influence on the upper atmosphere, is vital to understanding the changes that have occurred in the ozone layer.
In the UK, stratospheric ozone levels are monitored every winter and spring at Cambourne in Cornwall and Lerwick in the Shetland Isles.