Traceability for atmospheric total column ozone

Abstract

Ozone in the earth’s upper atmosphere absorbs ultraviolet radiation, preventing most of it reaching the ground.This is important because ultraviolet radiation can harm life on earth, and for example lead to skin cancer.Since the 1980s, it has been known that human-produced chlorofluorocarbons (CFCs) have led to recurring losses of total ozone in the Antarctic (the ozone hole), and these have also been recently observed in the Arctic, while in middle-latitudes, moderate ozone depletion has been observed.

The Montreal Protocol on Substances that Deplete the Ozone Layer is an international treaty signed in 1994 designed to protect the ozone layer by phasing out the production of substances that are responsible for ozone depletion, and it has been successful in reducing the emission of ozone-depleting substances.

However, monitoring of the recovery of the ozone layer requires accurate long-term observations with reliable and well understood instruments and the development of future instrumentation.

This project characterised key reference and network instruments for the traceability of ozone retrievals (or measurements), developed new instruments and devices for in-field characterisation of the existing network instruments and new ozone monitoring instruments, and generated new datasets for ozone absorption crosssections and extra-terrestrial solar reference spectrum.