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Statistical data set

Figure 15: Mean hours when O3 pollution was ‘Moderate’ or higher for urban background sites, 1992 to 2023

Updated 30 April 2024
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Site type Year Number of sites Daily Air Quality Index Mean number of hours per site
1992 Urban Background 4 mod_4 12
1993 Urban Background 8 mod_4 10.5
1994 Urban Background 13 mod_4 21.38461538
1995 Urban Background 12 mod_4 53.75
1996 Urban Background 18 mod_4 38.5
1997 Urban Background 31 mod_4 35.12903226
1998 Urban Background 42 mod_4 19.80952381
1999 Urban Background 42 mod_4 61.47619048
2000 Urban Background 41 mod_4 29.48780488
2001 Urban Background 43 mod_4 40.13953488
2002 Urban Background 45 mod_4 27.73333333
2003 Urban Background 47 mod_4 104.5744681
2004 Urban Background 50 mod_4 44.68
2005 Urban Background 49 mod_4 38.14285714
2006 Urban Background 48 mod_4 102.7708333
2007 Urban Background 45 mod_4 48.26666667
2008 Urban Background 43 mod_4 96.11627907
2009 Urban Background 41 mod_4 34.31707317
2010 Urban Background 42 mod_4 19.5
2011 Urban Background 43 mod_4 49.11627907
2012 Urban Background 42 mod_4 35.19047619
2013 Urban Background 41 mod_4 40.46341463
2014 Urban Background 42 mod_4 32.78571429
2015 Urban Background 42 mod_4 22.64285714
2016 Urban Background 41 mod_4 39.34146341
2017 Urban Background 41 mod_4 21.02439024
2018 Urban Background 42 mod_4 93.38095238
2019 Urban Background 39 mod_4 48.15384615
2020 Urban Background 39 mod_4 93.74358974
2021 Urban Background 38 mod_4 33.81578947
2022 Urban Background 40 mod_4 74.1
2023 Urban Background 52 mod_4 77.82692308
1992 Urban Background 4 mod_5 1
1993 Urban Background 8 mod_5 3.625
1994 Urban Background 13 mod_5 7.923076923
1995 Urban Background 12 mod_5 31.16666667
1996 Urban Background 18 mod_5 19.61111111
1997 Urban Background 31 mod_5 10.5483871
1998 Urban Background 42 mod_5 2.714285714
1999 Urban Background 42 mod_5 21.38095238
2000 Urban Background 41 mod_5 7.536585366
2001 Urban Background 43 mod_5 14.81395349
2002 Urban Background 45 mod_5 4.933333333
2003 Urban Background 47 mod_5 42.87234043
2004 Urban Background 50 mod_5 13.42
2005 Urban Background 49 mod_5 10
2006 Urban Background 48 mod_5 50.08333333
2007 Urban Background 45 mod_5 6.488888889
2008 Urban Background 43 mod_5 22.95348837
2009 Urban Background 41 mod_5 3.829268293
2010 Urban Background 42 mod_5 3.904761905
2011 Urban Background 43 mod_5 8.093023256
2012 Urban Background 42 mod_5 8.428571429
2013 Urban Background 41 mod_5 5.804878049
2014 Urban Background 42 mod_5 2.571428571
2015 Urban Background 42 mod_5 5
2016 Urban Background 41 mod_5 7.146341463
2017 Urban Background 41 mod_5 5.048780488
2018 Urban Background 42 mod_5 20.88095238
2019 Urban Background 39 mod_5 22.87179487
2020 Urban Background 39 mod_5 27.48717949
2021 Urban Background 38 mod_5 6.236842105
2022 Urban Background 40 mod_5 27.725
2023 Urban Background 52 mod_5 28.86538462
1992 Urban Background 4 mod_6 0
1993 Urban Background 8 mod_6 2.625
1994 Urban Background 13 mod_6 3.461538462
1995 Urban Background 12 mod_6 12.58333333
1996 Urban Background 18 mod_6 8.555555556
1997 Urban Background 31 mod_6 3.903225806
1998 Urban Background 42 mod_6 0.380952381
1999 Urban Background 42 mod_6 8.047619048
2000 Urban Background 41 mod_6 1.12195122
2001 Urban Background 43 mod_6 4.069767442
2002 Urban Background 45 mod_6 0.866666667
2003 Urban Background 47 mod_6 18.5106383
2004 Urban Background 50 mod_6 2.7
2005 Urban Background 49 mod_6 2.387755102
2006 Urban Background 48 mod_6 24.29166667
2007 Urban Background 45 mod_6 0.444444444
2008 Urban Background 43 mod_6 3.255813953
2009 Urban Background 41 mod_6 1.487804878
2010 Urban Background 42 mod_6 0.547619048
2011 Urban Background 43 mod_6 0.953488372
2012 Urban Background 42 mod_6 1.476190476
2013 Urban Background 41 mod_6 1.609756098
2014 Urban Background 42 mod_6 0.071428571
2015 Urban Background 42 mod_6 1.714285714
2016 Urban Background 41 mod_6 0.390243902
2017 Urban Background 41 mod_6 1.024390244
2018 Urban Background 42 mod_6 3.928571429
2019 Urban Background 39 mod_6 6.256410256
2020 Urban Background 39 mod_6 11.17948718
2021 Urban Background 38 mod_6 0.263157895
2022 Urban Background 40 mod_6 10.15
2023 Urban Background 52 mod_6 6.442307692
1992 Urban Background 4 high_7 0
1993 Urban Background 8 high_7 0.125
1994 Urban Background 13 high_7 1.461538462
1995 Urban Background 12 high_7 4.416666667
1996 Urban Background 18 high_7 1.666666667
1997 Urban Background 31 high_7 1.806451613
1998 Urban Background 42 high_7 0.142857143
1999 Urban Background 42 high_7 2.380952381
2000 Urban Background 41 high_7 0.097560976
2001 Urban Background 43 high_7 1.139534884
2002 Urban Background 45 high_7 0.311111111
2003 Urban Background 47 high_7 6.319148936
2004 Urban Background 50 high_7 0.52
2005 Urban Background 49 high_7 0.551020408
2006 Urban Background 48 high_7 10.1875
2007 Urban Background 45 high_7 0
2008 Urban Background 43 high_7 0.186046512
2009 Urban Background 41 high_7 0.219512195
2010 Urban Background 42 high_7 0
2011 Urban Background 43 high_7 0
2012 Urban Background 42 high_7 0.047619048
2013 Urban Background 41 high_7 0.024390244
2014 Urban Background 42 high_7 0
2015 Urban Background 42 high_7 0.428571429
2016 Urban Background 41 high_7 0
2017 Urban Background 41 high_7 0.219512195
2018 Urban Background 42 high_7 0.619047619
2019 Urban Background 39 high_7 1.58974359
2020 Urban Background 39 high_7 1.974358974
2021 Urban Background 38 high_7 0
2022 Urban Background 40 high_7 1.45
2023 Urban Background 52 high_7 0.769230769
1992 Urban Background 4 high_8 0
1993 Urban Background 8 high_8 0
1994 Urban Background 13 high_8 0
1995 Urban Background 12 high_8 0.25
1996 Urban Background 18 high_8 0.111111111
1997 Urban Background 31 high_8 0.225806452
1998 Urban Background 42 high_8 0
1999 Urban Background 42 high_8 0.285714286
2000 Urban Background 41 high_8 0
2001 Urban Background 43 high_8 0.093023256
2002 Urban Background 45 high_8 0
2003 Urban Background 47 high_8 0.765957447
2004 Urban Background 50 high_8 0
2005 Urban Background 49 high_8 0
2006 Urban Background 48 high_8 1.604166667
2007 Urban Background 45 high_8 0
2008 Urban Background 43 high_8 0
2009 Urban Background 41 high_8 0
2010 Urban Background 42 high_8 0
2011 Urban Background 43 high_8 0
2012 Urban Background 42 high_8 0
2013 Urban Background 41 high_8 0
2014 Urban Background 42 high_8 0
2015 Urban Background 42 high_8 0
2016 Urban Background 41 high_8 0
2017 Urban Background 41 high_8 0
2018 Urban Background 42 high_8 0
2019 Urban Background 39 high_8 0.076923077
2020 Urban Background 39 high_8 0
2021 Urban Background 38 high_8 0
2022 Urban Background 40 high_8 0
2023 Urban Background 52 high_8 0
1992 Urban Background 4 high_9 0
1993 Urban Background 8 high_9 0
1994 Urban Background 13 high_9 0
1995 Urban Background 12 high_9 0
1996 Urban Background 18 high_9 0
1997 Urban Background 31 high_9 0
1998 Urban Background 42 high_9 0
1999 Urban Background 42 high_9 0.095238095
2000 Urban Background 41 high_9 0
2001 Urban Background 43 high_9 0
2002 Urban Background 45 high_9 0
2003 Urban Background 47 high_9 0
2004 Urban Background 50 high_9 0
2005 Urban Background 49 high_9 0
2006 Urban Background 48 high_9 0.125
2007 Urban Background 45 high_9 0
2008 Urban Background 43 high_9 0
2009 Urban Background 41 high_9 0
2010 Urban Background 42 high_9 0
2011 Urban Background 43 high_9 0
2012 Urban Background 42 high_9 0
2013 Urban Background 41 high_9 0
2014 Urban Background 42 high_9 0
2015 Urban Background 42 high_9 0
2016 Urban Background 41 high_9 0
2017 Urban Background 41 high_9 0
2018 Urban Background 42 high_9 0
2019 Urban Background 39 high_9 0
2020 Urban Background 39 high_9 0
2021 Urban Background 38 high_9 0
2022 Urban Background 40 high_9 0
2023 Urban Background 52 high_9 0
1992 Urban Background 4 vhigh_10 0
1993 Urban Background 8 vhigh_10 0
1994 Urban Background 13 vhigh_10 0
1995 Urban Background 12 vhigh_10 0
1996 Urban Background 18 vhigh_10 0
1997 Urban Background 31 vhigh_10 0
1998 Urban Background 42 vhigh_10 0
1999 Urban Background 42 vhigh_10 0
2000 Urban Background 41 vhigh_10 0
2001 Urban Background 43 vhigh_10 0
2002 Urban Background 45 vhigh_10 0
2003 Urban Background 47 vhigh_10 0
2004 Urban Background 50 vhigh_10 0
2005 Urban Background 49 vhigh_10 0
2006 Urban Background 48 vhigh_10 0
2007 Urban Background 45 vhigh_10 0
2008 Urban Background 43 vhigh_10 0
2009 Urban Background 41 vhigh_10 0
2010 Urban Background 42 vhigh_10 0
2011 Urban Background 43 vhigh_10 0
2012 Urban Background 42 vhigh_10 0
2013 Urban Background 41 vhigh_10 0
2014 Urban Background 42 vhigh_10 0
2015 Urban Background 42 vhigh_10 0
2016 Urban Background 41 vhigh_10 0
2017 Urban Background 41 vhigh_10 0
2018 Urban Background 42 vhigh_10 0
2019 Urban Background 39 vhigh_10 0
2020 Urban Background 39 vhigh_10 0
2021 Urban Background 38 vhigh_10 0
2022 Urban Background 40 vhigh_10 0
2023 Urban Background 52 vhigh_10 0