1. Linking the meteorological conditions to air pollution in Italy
Massimo D’Isidoro, Mihaela Mircea
ENEA, National Agency for New Technologies, Energy and Sustainable
Economic Development, via Martiri di Monte Sole 4, 40129, Bologna, Italy
17th Task Force on Measurement and Modelling Meeting
May 2016 in Utrecht, Netherlands

2. Outline
daily exceedances of PM10 and NO2 limit values and associated atmospheric circulation types (CTs)
evaluation of spatial extension and concomitance of exceedances at monitoring stations in Po valley
selection of an acute pollution event for PM10 and of alternative meteorological conditions
impact of meteorology on PM10 and its components with AMS-MINNI
summary of results

3. PM10 concentrations at Milan and atmospheric circulation types
(Valverde et al. 2014, software COST 733&ERA-Interim reanalysis data CT2(VCT1&3),CT4(VCT5),CT5(VCT2),CT6(VCT4&VCT6)

4. PM10 concentrations at Milan and circulation types
daily 50 μg/m3 exceeded more than 35 times a calendar year! (Directive 50/2008)

5. NO2 concentrations at Milan and circulation types
200 μg/m3,not exceeded more than 18 times a calendar year (Directive 50/2008)

6. Exceedances of PM10 limit value at Bologna and Milan: background stations

7. Exceedances of PM10 limit value at traffic stations in Bologna and Milan: selection of an acute pollution event

8. Alternative meteorological conditions according to daily CT
28 January-1 February 2010
1-5 January 2003
13-17 February 2005
24-28 January 2007
24-28 December 2007

9. Probing the atmosphere at urban and rural stations
Urban stations: Milano-Verziere and Bologna-San Felice
Rural stations: Tavazzano and San Pietro Capofiume

10. Temperature and wind speed for the selected meteorological periods

11. Impact of meteorological conditions on PM10 concentrations: AMS-MINNI
29&30 January 2010
2010, 2003: CT4
2005, 2007j: CT2
2007d: CT6

12. Differences in PM10 components, temperature and wind speed: 2005 -2010

13. Differences in PM10 concentrations: 2005 - 2010
29 January 2010
mg/m3
30 January 2010
mg/m3

14. Differences in temperature, wind speed and PM10 concentrations at Bologna-San Felice
30 January 2010
2010, 2003: CT4
2005, 2007g: CT2
2007d: CT6

15. Differences in temperature, wind speed and PM10 concentrations at Milan-Verziere
29 January 2010
2010, 2003: CT4
2005, 2007g: CT2
2007d: CT6

16. Differences in temperature, wind speed, mixing layer height and PM10 concentrations during the days with exceedances
2007j
2003
2005
2007d
DT(C) - bubble
2003
2007j
2007d
2005
DT(C) - bubble
2007j
2005
2007d
2003: -143 m
DHmix(m) - bubble
2003: -115 m
2007j
2007d
2005
DHmix(m) - bubble

17. Differences in PM10 due to emissions reductions

18. Summary of results
the decrease of concentrations due to meteorological conditions were from 45 to 66 mg/m3 at Bologna and from 68 to 114 mg/m3 at Milan during the days with maximum exceedances.
during these days, the PM10 concentrations decrease with the increase of the wind speed, but no relationship with temperature is evident
substantial decreases of primary anthropogenic aerosols is observed at urban stations (APANT and POA) while the decrease of inorganic secondary aerosols (ANO3 and ANH4 mainly) is observed at both urban and rural stations
the relationship between the circulation type and PM10 exceedances is weak/qualitatevely: local effects are dominant?
impact of meteorology is 10 times higher than the impact of 20% reduction of emissions (primary anthropogenic aerosols and gas precursors)
further investigation on local dynamical and thermodynamical parameters ….

19. Circulation Types