§ Lord Juddasked Her Majesty's Government:
What is their evaluation of the prediction by the British Antarctic Survey that the Antarctic ozone hole could be replicated over the Arctic within the next 20 years; and what they believe the consequences, including health risks, would be. [HL4644]
§ The Parliamentary Under-Secretary of State, Department of the Environment, Transport and the Regions (Lord Whitty)The British Antarctic Survey did not predict that the Antarctic ozone hole could be replicated over the Arctic within the next 20 years but did quote US research suggesting such an event might be possible. The Arctic is not prone to the consistently stable and cold conditions that promote ozone loss in the Antarctic, nor does the spring ozone depletion in the Arctic last into summer as it does in the Antarctic.
The amount of ozone depleting substances in the stratosphere is decreasing slowly but if the stratosphere continues to cool over the next few decades, then it is possible that ozone levels over the Arctic could fall to the threshold level defined for an ozone hole in any individual year. Very low levels are unlikely to occur consistently year after year or to be as low as those observed in the Antarctic.
A reduction in the level of ozone overhead increases the amount of harmful ultraviolet sunlight (UVB) reaching the surface and an increase in UVB can damage the skin and eyes and cause changes in the immune system. A year with significant Arctic ozone depletion would result in perhaps a 10 per cent decrease in the amount of ozone above the UK in the spring; this is the same as the average decrease in ozone that has already occurred over the UK since the end of the 1970s.