HC Deb 06 June 1990 vol 173 cc642-5W
Mr. Dobson

To ask the Secretary of State for the Environment (1) pursuant to the answer of 1 May,Official Report, columns 502–3, if he will give comparable figures on nitrogen dioxide, ozone and acidity of rain at each of the monitoring sites then in operation for each year since 1979; (2) pursuant to the answer of 1 May, Official Report, columns 502–3, if he will give comparable figures for suphur dioxide concentrations in each region for every year since 1979.

Mr. Trippier

The information requested is in the table. Additional data have been published in the relevant Department of the Environment scientific review group and other reports: "Ozone in the United Kingdom" (United Kingdom photochemical oxidants review group), "Acidity in United Kingdom Fresh Waters" (United Kingdom acid waters review group second report), "Acid Deposition in the United Kingdom" (United Kingdom review group on acid rain second report) and "Lake Acidification in the United Kingdom" (paleoecology research unit, University College London). Copies of these publications have been placed in the Library of the House.

A. NO2 annual mean (am) and 98th percentile (98 percentile):
Units: parts per billion (ppb).
Site 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989
EC Directive sites
Central London
am 34 33 35 43 39 43 32 35 39 35 39
98 percentile 64 66 71 110 73 81 63 64 85 74 80
West London
am — — — — — — — — 35 37 42
98 percentile — — — — — — — — 84 92 112
Glasgow
am — — — — — — — — 31 30 27
98 percentile — — — — — — — — 69 57 61
Manchester
am — — — — — — — — 29 28 25
98 percentile — — — — — — — — 65 67 62
Walsall
am — — — — — — — — 30 26 29
98 percentile — — — — — — — — 62 54 59
Billingham
am — — — — — — — — 23 21 22
98 percentile — — — — — — — — 63 58 60
Non Directive sites:
Cromwell Road
am 36 — — 46 68 50 48 40 — — 45
98 percentile 82 — — 117 209 119 128 109 — — 105
Stevenage
am 24 18 19 22 20 23 — 21 27 24 25
98 percentile 71 43 50 54 47 57 — 52 72 53 56

B. Ozone: exceedances of 60pph hourly average
Site 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989
Stevenage 64 11 7 242 178 324 108 89 36 10 85
Central London 29 15 31 10 6 6 146 68 9 3 74
Sibton 66 2 358 157 207 72 63 — 46 76 212
Aston Hill — — — — — — — 47 45 83 143
Lullington Heath — — — — — — — 0 106 112 401
Strath Vaigh — — — — — — — — 32 53 28
High Muffles — — — — — — — — 0 49 184
Lough Navar — — — — — — — — 34 49 74
Yarner Wood — — — — — — — — 21 51 360
Ladybower — — — — — — — — — 20 173
Harwell — — — — 117 173 70 77 51 16 170
Bottesford 503 458 54 238 138 201 94 93 59 10 82
Bush — — — — — — — 11 53 33 63
Eskdalemuir — — — — — — — 30 49 28 99
Great Dun Fell — — — — — — — 96 167 131 204
Wharley Croft — — — — — — — 21 36 34 129
Glazebury — — — — — — — — — 22 39

C. Acidity of rain as precipitation weighted mean acidity in microgramme equivalents per litre:
Site 1986 1987 1988 1989
Achanarras — 19 25 25
Strath Vaigh Dam — 16 16 13
River Mharcaidh 22 22 21 20
Glen Dye — 45 46 36
Balquhidder 21 32 24 20
Whiteadder 40 36 47 35
Eskdalemuir 21 25 27 20
Redesdale 41 44 52 33
Loch Dee 29 23 19 15
Cow Green Reservoir 27 31 34 23
Bannisdale 30 27 28 24
High Muffles — 63 72 55
Thorganby 75 73 88 84
Jenny Hum 89 100 85 64
Driby 42 43 42 47
Wardlow Hay Cop 29 45 33 37

Site 1986 1987 1988 1989
Beddgelert 17 19 17 15
Bottesford 61 76 81 48
Plynlimon — 15 11 14
Stoke Ferry 35 36 30 40
Preston Montford 18 25 25 36
Llyn Brianne 16 21 18 19
Tycanol Wood 16 17 15 18
Woburn 45 51 37 37
Flatford Mill 33 43 35 35
Compton 25 28 16 25
Barcombe Mills 19 22 13 15
Yarner Wood 17 20 14 20
Goonhilly 20 23 15 19
Lough Navar 11 10 10 10
Hillsborough Forest — — — 13
Isle of Man 28 34 27 24

D. SO2 concentrations by region
Units: microgrammes per cubic meter
Region 1979–80 1980–81 1981–82 1982–83 1983–84 1984–85 1985–86 1986–87 1987–88
Scotland 60 49 53 40 40 43 38 36 32
North 54 42 43 35 33 30 30 33 35
North West 84 63 63 49 48 44 39 38 41
Yorks/Humber 86 69 78 68 67 59 57 51 50
East Midlands 76 58 65 54 54 47 45 47 46
West Midlands 73 61 64 54 57 49 44 44 39
Wales 48 41 39 35 35 36 28 26 24
East Anglia 51 50 50 35 34 28 25 27 24
London 78 68 66 55 47 48 39 42 37
South East 57 50 46 39 37 38 37 37 31
South West 49 45 43 37 35 34 37 34 25
Northern Ireland 47 40 47 56 46 58 64 70 67