The Scottish Environment Statistics - 1998

4. ATMOSPHERE

Table 4.10 Ozone measurements, 1991-19961 1991 1992 1993 1994 1995 1996 Strath Vaich Annual mean (ppb)2 33 35 34 37 34. 34 98% percentile of hourly values (ppb) 56 59 50 54 51 50 Number of running 8 hours >= 60ppb3 69 159 4 49 51 29 Number of high periods4 0 0 0 0 0 0 Number of very high periods4 0 0 0 0 0 0 Number running 8 hour/means5 >= 50ppb6 349 377 127 276 282 111 Data capture, % 89 95 81 74 95 94 Bush Estate Annual mean (ppb)2 24 27 26 28 26 27 98% percentile of hourly values (ppb) 42 50 44 46 45 48 Number of running 8 hours >= 60ppb3 7 46 0 12 19 53 Number of high periods4 0 0 0 0 0 1 Number of very high periods4 0 0 0 0 0 0 Number running 8 hour/means5 >= 50ppb6 19 157 0 49 54 112 Data capture, % 97 99 96 98 81 99 Eskdalemuir Annual mean (ppb)2 26 27 25 28 28 26 98% percentile of hourly values (ppb) 50 54 46 49 54 45 Number of running 8 hours >= 60ppb3 31 66 35 22 91 23 Number of high periods4 0 0 6 0 7 0 Number of very high periods4 0 0 0 0 0 0 Number running 8 hour/means5 >= 50ppb6 178 277 83 124 200 77 Data capture, % 97 98 97 99 98 98 Edinburgh Centre Annual mean (ppb)2 .. - 13 15 15 16 98% percentile of hourly values (ppb) .. .. 32 36 37 36 Number of running 8 hours >= 60ppb3 .. - 0 0 4 4 Number of high periods4 .. 0 0 0 0 0 Number of very high periods4 .. 0 0 0 0 0 Number running 8 hour/means5 >= 50ppb6 .. 0 0 0 10 15 Data capture, % .. 24 95 95 97 98 Glasgow Centre Annual mean (ppb)2 .. .. .. .. .. .. 98% percentile of hourly values (ppb) .. .. .. .. .. .. Number of running 8 hours >= 60ppb3 .. .. .. .. .. 0 Number of high periods4 .. .. .. .. .. 0 Number of very high periods4 .. .. .. .. .. 0 Number running 8 hour/means5 >= 50ppb6 .. .. .. .. .. 1 Data capture, % .. .. .. .. .. 42 Source: AEA Technology NETCEN 1 Figures are for calendar year. 2 Parts per billion. 3 WHO guideline. 4 UK air quality bands: high band-hourly average 90 - 179ppb (EC Directive Population Information Threshold is 90ppb). Very high band-hourly average 180 or more ppb (EC Directive Population Warning Threshold is 180ppb). 5 Calculated for each hour "h" by averaging concentrations between hours "h" and "h-7". 6 UK National Strategy.