Post on 12-Feb-2016
description
UK Air Quality Indicators
Janet DixonAir and Environment Quality Division, Department of Environment, food and
Rural Affairs, UK
Air quality monitoring network
UK Air Pollution Index• Used for providing a public summary of current and forecast air pollution• 1-10 scale in 4 bands for 5 pollutants - ozone, PM10, SO2, NO2, CO• Produced for all 16 UK zones and largest 16 of the 28 UK agglomerations• Levels reported = highest for any single pollutant• Has health advice associated with each band• Mainly driven by PM10 and O3
• Further information: www.airquality.co.uk/archive/standards.php#band
UK Air Pollution IndexO3 NO2 PM10 SO2 CO
µg m-3 (mg m-3 for CO)
8hr running mean or hourly mean
Hourly mean 24 hour running mean
15 minute mean
8 hour running mean
Low(1-3)
0 – 99 0 - 286 0 – 49 0 – 265 0 – 11.5
Moderate (4-6)
100 – 179 287 – 572 50 – 74 266 – 531 11.5 – 17.3
High(7-9)
180 – 359 573 – 763 75 – 99 532 – 1063
17.4 – 23.1
Very high (10)
> 360 > 764 > 100 > 1063 > 23.2
UK Air Quality Headline Indicator
• UK Sustainable Development Strategy • One of 15 headline indicators• Developed in 1998, reviewed in 2002• Captures ‘acute’ air quality issues• Counts number of days of moderate or higher (from AP Index)
pollution for 5 ‘acute’ pollutants – ozone, PM10, SO2, NO2, CO• Does not correspond directly to UK Air Quality Strategy
objectives
Headline indicator
• Maximum number of sites used is fixed • Pre-1998 – up to 34 urban and 14 rural/remote• 1998 – 34 urban and 14 rural/remote• 2002 – 49 urban and 16 rural/remote
• To be included sites need minimum range of pollutants and data capture (>75%)• Rural – at least O3
• Roadside/kerbside – at least PM10
• Other urban – at least O3, PM10 and SO2
• Fairly robust to changes in network• Urban sites cover 26 of the 28 UK agglomerations
0
10
20
30
40
50
60
70
1987 1989 1991 1993 1995 1997 1999 2001 2003
Days when air pollution is moderate or higher: 1987-2003
Urban sites
Rural sites
Final 2003 indicator
0
10
20
30
40
50
60
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
Causes of air pollution at urban sites
total urban
0
10
20
30
40
50
60
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
particles
sulphur dioxide
Causes of air pollution at urban sites
total urban
0
10
20
30
40
50
60
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
ozone
particles
sulphur dioxide
Causes of air pollution at urban sites
total urban
The main episodes driving 2003
• Exceptionally hot summer – • high ozone
• Particulate episodes in spring, including • UK and European element• Saharan dust storm
9
10
11
12
13
14
15
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
Sum
mer
Tem
pera
ture
0
10
20
30
40
50
60
70
80
Ozo
ne D
ays
Urban
Rural
• high secondary particulates (SO2 & NO2 gas converted to particulate sulphates & nitrates)
0
5
10
15
20
25
30
35
40
45
50
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003Year
Con
cent
ratio
ns (
m g/m
3)
AverageRange
40 ug/m3 objective20 ug/m3 prov. objective
PM100
10
20
30
40
50
60
70
80
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003Year
Con
cent
ratio
ns (
m g/m
3 )
Average
Range
40 ug/m3 objective NO2
0
10
20
30
40
50
60
70
80
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003Year
Con
cent
ratio
ns (
m g/m
3 )
Average
Range
20 ug/m3 vegetationprotection
SO2
•Indicator picks up peaks – what about long-term trends?
but….
….for ozone:
0
10
20
30
40
50
60
70
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
Year
Conc
entra
tions
(m g/m
3)
Average
Range
• 2003 was an exceptional year.• Headline Indicator accurately reflects poor air
quality in 2003 (but not every aspect).• Headline indicator is currently being reviewedFor the future:
Conclusions
long-term trend downwards for most pollutants.
ozone increasing - global ozone precursor emissions, (?) global warming