The ozone hole over the South Pole is larger than ever, say scientists. But there are signs that it will shrink in the future. Our science editor David Whitehouse reports. During the next few weeks, the 1998 springtime Antarctic ozone hole will reach its maximum size. This ozone hole has opened up over Antarctica every year since 1978.
Ozone is a form of molecular oxygen.
It is an irritating pale blue gas, explosive and toxic. Man-made chemicals such as Cfc's are believed to have risen in the atmosphere and started chemical reactions that destroy ozone. It is approximately three times the area of Australia and is the largest ozone hole ever. Dr Solomon discovered that chemical reactions destroy ozone on surfaces such as the ice crystals within high-altitude 'polar stratospheric clouds' as well as on other atmospheric particles high in the atmosphere. Just as polar stratospheric clouds, volcanic particles make chlorine from Cfc's more effective at ozone destruction,' she adds.