§ Mrs. GormanTo ask the Secretary of State for the Environment if he will give the relative proportions of(a) water vapour, (b) methane and (c) sulphur dioxide in the atmosphere.
§ Mr. MacleanThe concentrations in the lower atmosphere of water vapour and methane relative to 1049W sulphur dioxide are on average approximately 10 million and 1,000 respectively. Both water vapour and sulphur dioxide concentrations vary considerably with geographical location, altitude and meteorological conditions.