The Scottish Environment Statistics - 1998

4. ATMOSPHERE

Table 4.11 Nitrogen dioxide measurements, 1991-19961 1991 1992 1993 1994 1995 1996 Glasgow City Chambers Annual mean (ppb)2 26 25 27 26 26 27 98% percentile of hourly values (ppb) 52 50 56 50 51 57 Number of annual means >= 21ppb3,5 1 1 1 1 1 1 Number of hours >= 110ppb3 16 0 0 2 0 3 Number of high periods4 0 0 0 0 0 0 Number of very high periods4 0 0 0 0 0 0 Number of hours >= 150ppb5 6 0 0 0 0 0 Data capture, % 99 99 89 98 97 97 Edinburgh Centre Annual mean (ppb)2 .. .. 27 26 26 25 98% percentile of hourly values (ppb) .. .. 54 51 54 49 Number of annual means >= 21ppb3,5 .. .. 1 1 1 1 Number of hours >= 110ppb3 .. 0 1 0 2 0 Number of high periods4 .. 0 0 0 0 0 Number of very high periods4 .. 0 0 0 0 0 Number of hours >= 150ppb5 .. 0 0 0 0 0 Data capture, % .. 24 95 96 92 96 Strath Vaich Annual mean (ppb)2 .. 0.7 .. 1.1 0.5 0.8 98% percentile of hourly values (ppb) .. 4.5 .. 8.3 2.6 5.3 Number of annual means >= 21ppb3,5 .. 0 .. 0 0 0 Number of hours >= 110ppb3 0 0 0 0 0 0 Number of high periods4 0 0 0 0 0 0 Number of very high periods4 0 0 0 0 0 0 Number of hours >= 150ppb5 0 0 0 0 0 0 Data capture, % 44 85 42 68 86 85 Glasgow Centre Annual mean (ppb)2 .. .. .. .. .. .. 98% percentile of hourly values (ppb) .. .. .. .. .. .. Number of annual means >= 21ppb3,5 .. .. .. .. .. .. Number of hours >= 110ppb3 .. .. .. .. .. 0 Number of high periods4 .. .. .. .. .. 0 Number of very high periods4 .. .. .. .. .. 0 Number of hours >= 150ppb5 .. .. .. .. .. 0 Data capture, % .. .. .. .. .. 42 Source: AEA Technology NETCEN 1 Figures are for calendar year. 2 Parts per billion 3 WHO hourly guidelines. 4 UK air quality bands: high band hourly average 300-399ppb. very high band hourly average 400ppb or more. 5 UK National Strategy