OZONE DEPLETION

Ozone in the upper atmosphere protects life on the Earth's surface by absorbing most of the sun's harmful ultraviolet B radiation. Human activity has been responsible for increasing the concentrations of ozone depleting substances in the atmosphere. The main substance responsible for ozone depletion is chlorofluorocarbons (CFCs).

Australia stopped the importation and production of CFCs during the 1990s. This saw the consumption of ozone depleting substances fall by 86%, from 832 Ozone Depleting Potential Tonnes (ODPT) in 1999 to 119 ODPT in 2009. This current level (119 ODPT in 2009) represents less than 1% of Australia's consumption of ozone depleting substances in 1989.

In the past decade, the ozone 'hole' over Antarctica has stayed at its current size of about 26 million km², following two decades of rapid growth (BOM, 2010c).

Synthetic Greenhouse Gases were largely introduced as replacements for some ozone-depleting substances. Three of the six Kyoto Protocol gases - hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride (SF) - are Synthetic Greenhouse Gases. While these gases do not present a direct risk to the ozone layer, they can contribute to the enhanced greenhouse effect if emitted to the atmosphere.