§ Mr. HardyTo ask the Secretary of State for the Environment what is his present estimate of the size of and coverage of the ozone layer; and what estimates were made in 1990 and 1985.
§ Mr. MacleanThe ozone layer covers the entire globe but a progressive depletion in its thickness has been observed since the mid-1980s, with strong evidence that this is due to man-made ozone-depleting chemicals. Assessments of depletion published in 1992 by the WMO/UNEP Scientific Assessment Panel indicated a total ozone loss rate of 8 per cent. per decade in the early spring over northern mid latitudes (30–60°N), a peak downward trend at high southern latitudes in October-December of greater than 35 per cent. per decade and an average global depletion of 3 per cent. per decade.
52WAssessments by the International Ozone Trends Panel have been published by the World Meteorological Organisation in 1985, 1988, 1989 and 1992 and by the Departments stratospheric ozone review group in 1987, 1988, 1990 and 1991. Copies of these reports have been placed in the Library of the House.
§ Mr. DalyellTo ask the Secretary of State for the Environment if he will make a statement on the results of the conference on the ozone layer in Copenhagen.
§ Mr. MacleanI refer the hon. Member to the answer that I gave on 27 November 1992 to the hon. Member for Burnley (Mr. Pike),Official Report, column 85.