Origin and features of ultrafine particles in Barcelona

Transcription

1 Instituto Nacional de Meteorología-INM National Institute for Meteorology Origin and features of ultrafine particles in Barcelona Sergio Rodríguez 1,2,3*, Jorge Pey 1, Noemí Perez 1, Xavier Querol 1,#, Andrés Alastuey 1, R. Van Dingenen 3, J.P. Putaud 3 1, Associated Unit on Aerosol Research: -Institute of Earth Science Jaume Almera, CSIC, Barcelona. -University of Huelva, Campus del Carmen, Huelva. 2, Associated Unit on Air Pollution Research: -Institute of Earth Science Jaume Almera, CSIC, Barcelona. -Izaña Atmospheric Observatory, La Marina 2, planta 6, Santa Cruz de Tenerife. *, srodriguez@inm.es # xavier.querol@ija.csic.es 3, European Commission DG Joint Research Centre, Institute for Environment and Sustainability, T.P. 29, Ispra (VA) 212.

2 1. Introduction: PM monitoring program in Barcelona Daily cycles 3. Events and seasonal evolution -local urban pollution events - clean air events, -ultrafine particles events 4. Summary

3 Studies on PM and urban air quality: since 1999 PM chemical characterization & mass closure Time series analysis (back to 1995) Modelling : L HO site BARCELONA 21-22: SAGRERA site 23-27: IJA site 23: number concentration measurements were added to the IJA aerosol program

4 IJA site: IJA N

5 IJA site: central urban background site UNIVERSITY CAMPUS Differential Mobility Particle Sizer 1-8nm PM1 & PM2.5 sampling on filter

6 6 PM1, µg/m 3 N, cm

7 6 PM2.5, µg/m 3 N, cm

8 Correlation coefficient between number size distribution and PM r.4.2. N4-8 N3-4 N2-3 N1-2 N5-1 N3-5 N2-3 N1-2

9 Mean values 2 dn/dlogd, 1/cm 3 ds/dlogd, µm 2 /cm 3 dv/dlogd, µm 3 /cm particle diameter, nm DpN: 36nm DpN: peak diameter for dn/dlogd N1-8: 168cm -3 N1-2: 1941cm -3 DpS: 233nm DpV: 39nm N2-3: 3386cm -3 N3-5: 3988cm -3 N5-1: 593cm -3 86%: ultrafine N1-2: 1588cm -3 N2-415: 496cm -3 N415-8: 49cm -3

10 1. Introduction: PM monitoring program in Barcelona Daily cycles 3. Events and seasonal evolution -local urban pollution events - clean air events, -ultrafine particles events 4. Summary

11 2. Daily cycles N1-1, cm NO, µg/m 3 N1-2, cm NO, µg/m 3 Monday Tuesday Wednesday Thursday Friday Saturday Sunday

12 2. Daily cycles N1-1, cm NO, µg/m 3 DpN, nm Monday Tuesday Wednesday Thursday Friday Saturday Sunday

13 2. Daily cycles r Correlation coefficient: gases & dn/dlogd Weekly cycles particle diameter, nm NO NO 2 CO SO 2

14 2. Daily cycles Correlation coefficient: NO & dn/dlogd nm 1-3 nm NO r particle diameter, nm Nucleation during the dilution and cooling of the vehicle exahust and subsequent particle growth by condensation soot emissions heavy duty engines?

15 2. Daily cycles dn/dlogd, cm h 7h 13h 1 1 particle diameter, nm 2 dn/dlogd: morning / night ratio 2-4 nm ratio particle diameter, nm

16 1. Introduction: PM monitoring program in Barcelona Daily cycles 3. Events and seasonal evolution -local urban pollution events - clean air events, -ultrafine particles events 4. Summary

17 3. Events and seasonal evolution -local urban pollution (winter) concatenations of: -Local urban pollution -Atlantic air masses advections correlated day-to-day variations in the daily mean values of N1-1, DpN & PM2.5

18 3. Events and seasonal evolution: local urban pollution DpN, nm PM2.5, µg/m February N1-8, cm -3 N1-1, cm -3 clean air 1-Feb-24 Local urban pollution 4-Feb-24 clean air 9-Feb-24

19 3. Events and seasonal evolution: local urban pollution not local urban pollution: Saharan dust DpN, nm PM2.5, µg/m N1-8, cm -3 N1-1, cm -3 boundary layer depth masl February wind speed, m/s

20 3. Events and seasonal evolution: local urban pollution DpN, nm PM2.5, µg/m N1-8, cm -3 N1-1, cm -3 Both ultrafine and PM2.5 particles increase during local urban pollution events, however they behave in deferent ways

21 3. Events and seasonal evolution: local urban pollution ultrafine particles DpN, nm PM2.5, µg/m N1-8, cm -3 N1-1, cm N1-1, cm February NO, µg/m 3

22 Relationship between N1-1 and NOx Morning rush hours (7-9h) N1-1, cm -3 N1-1, cm -3 N1-1, cm < TºC < 1 y = x R2 =.76 December-February 1 < TºC < 15 y = x R2 =.85 November-March 15 < TºC y = 196.1x R2 =.76 May - October 15 3 NOx, µg/m 3 Ultrafine particles formation is enhanced under low temperatures: winter maximum during morning rush hours

23 3. Events and seasonal evolution: local urban pollution ultrafine particles cm N1-1 J F M A M J J A S O N D weekdays cm N1-1 J F M A M J J A S O N D

24 3. Events and seasonal evolution: local urban pollution ultrafine particles r N1-2 N2-3 N3-5 based on 93 daily data N4-8 N3-4 N2-3 N1-2 N5-1 OM BC nss-so = 4 NO - 3 NH + 4 r PM2.5 BC OM trace based on 93 daily data NH 4 + NO 3 - N1 N1-1 N1-8 SO 4 = Min. dust Sea-salt

25 3. Events and seasonal evolution: local urban pollution PM2.5 not local urban pollution: Saharan dust DpN, nm PM2.5, µg/m N1-8, cm -3 N1-1, cm -3 Saharan dust DpN, nm PM2.5, µg/m February NO, µg/m 3

26 3. Events and seasonal evolution: local urban pollution PM2.5 DpN, nm PM2.5, µg/m NO 3- : OM: February µg/m µg/m NO, µg/m 3

27 3. Events and seasonal evolution: local urban pollution PM2.5 DpN, nm NO 3-5 J F M A M J J A S O N D

28 3. Events and seasonal evolution: local urban pollution local urban pollution: WINTER -PM2.5 particles events (night) due enhancements in the condensation of semi-volatile species at night: low temperatures, low dilution (low wind spped and low boundary layer depth), -ultrafine particles events (rush hours) due enhancements in the ultrafine particles formation in the morning rush hours during the vehicle exhaust dilution and cooling: low temperatures, low dilution (low wind speed and low boundary layer depth),

29 1. Introduction: PM monitoring program in Barcelona Daily cycles 3. Events and seasonal evolution -local urban pollution events - clean air events, -ultrafine particles events 4. Summary

30 3. Events and seasonal evolution: clean air events

31 3. Events and seasonal evolution cm morning rush hours peak (7-9h mean) N1-1 N1 PM µg m Wind speed, m/s

32 3. Events and seasonal evolution cm morning rush hours peak (7-9h mean) N1-1 N1 PM µg m -3 N1-5 / N1-8 N1-1 / N Wind speed, m/s 2 1 N1-2 / N1-8

33 3. Events and seasonal evolution Correlation coefficient: wind speed vs. dn/dlogd 2nm 8 dn/dlogd, cm -3 r Particle diameter, nm x.1-.6 m/s (1-1th) m/s (25-5th) m/s (75-9th) 5.-1 m/s (95-1th)

34 2 ultrafine particle in Barcelona 3. Events and seasonal evolution Wind speed, m/s N1-2 / N nm soot Wind speed, m/s N1-5 / N1-8 N5-1 / N1-8 N1-1 / N1-8

35 1. Introduction: PM monitoring program in Barcelona Daily cycles 3. Events and seasonal evolution -local urban pollution events - clean air events, -ultrafine particles events 4. Summary

36 3. Events and seasonal evolution: ultrafine particles events DpN, nm PM2.5, µg/m N1-8, cm -3 N1-1, cm N1-1, cm NO, µg/m 3 February 24

37 3. Events and seasonal evolution: ultrafine particles events DpN, nm PM2.5, µg/m N1-8, cm -3 N1-1, cm N1-2, cm NO, µg/m 3 February 24

38 3. Events and seasonal evolution: ultrafine particles events not local urban pollution: Saharan dust DpN, nm PM2.5, µg/m N1-8, cm -3 N1-1, cm -3 DpN, nm PM2.5, µg/m NO, µg/m 3 February 24

39 3. Events and seasonal evolution: ultrafine particles events - primary vehicle exhaust emisions, - role of nucleation in ambient air?

40 3. Events and seasonal evolution: ultrafine particles events N1-2>6cm -3 & PM2.5<4µg/m 3 ~8 hourly events/year 1 N1-2, cm PM2.5, µg/m 3

41 3. Events and seasonal evolution: ultrafine particles events Hourly N1-2>6cm -3 & PM2.5<4µg/m 3 ~8 events/year 2 Frequency, % time of day

42 3. Events and seasonal evolution: ultrafine particles events Ambient air nucleation event O 3, µg/m 3 N1-8, cm -3 NO, µg/m 3 NO, µg/m 3 Road traffic emissions nucleation ambient air 4-7, cm -3 /h O 3 N1-2 NO DpN NO 15nm/h time, 14 July N1-2, cm -3 N1-2, cm -3 DpN, nm regular daily evolution

43 3. Events and seasonal evolution: ultrafine particles events New particle formation in ambient air (nucleation events) Road traffic emissions nucleation ambient air N1-8, cm -3 O 3, µg/m 3 NO, µg/m , cm -3 /h O 3 N1-2 NO N1-2, cm -3 N1-2, cm ambient air nucleation events / year, Nucleation ambient air N cm -3 N cm -3 Nucleation exhaust Primary emission NO, µg/m NO 15nm/h DpN DpN, nm N1-2 N cm cm time, 14 July 24

44 1. Introduction: PM monitoring program in Barcelona Daily cycles 3. Events and seasonal evolution -local urban pollution events - clean air events, -ultrafine particles events 4. Summary

45 Summary Main features of ultrafine particles in Barcelona: -road traffic: the most important source of ultrafine particles, 1-8nm: 86% of the particles are ultrafine, dn/dlogd: mode 36nm -temperature influences on the ultrafine particles formation. Maximum in ultrafine particle concentrations in winter during the morning rush hours. - classical winter PM2.5 pollution events ultrafine particle pollution, PM2.5 formation enhanced at night condensation of semi-volatile material, Ultrafine particles formation fresh emissions morning, -additional ultrafine particles pollution events not associated with the classical winter PM2.5 episodes -very low frequency of nucleation events in ambient air (2-4 events/year),

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