Presentation is loading. Please wait.

Presentation is loading. Please wait.

Pollution levels plummet in clean air fight (but…) Ian Longley School of Earth, Atmospheric & Environmental Sciences University of Manchester.

Similar presentations


Presentation on theme: "Pollution levels plummet in clean air fight (but…) Ian Longley School of Earth, Atmospheric & Environmental Sciences University of Manchester."— Presentation transcript:

1 Pollution levels plummet in clean air fight (but…) Ian Longley School of Earth, Atmospheric & Environmental Sciences University of Manchester

2 Air Quality Objectives UK-wide Automated Urban and Rural Networks Bury (M60)Piccadilly GardensNorth-West

3 SO 2 ‘plummets’

4 The pollutants that matter:

5 Nitrogen Dioxide (NO 2 ) Particulate Matter (PM 10 )

6 PM 10 2003 - 2006

7 PM 10 2004 - 2006

8 PM 10 2003 - 2006

9 PM 10 1996 - 2006

10 2003

11 Urban PM 10 emission trends

12 2003: a bad year for air quality

13 Is PM 10 the right metric? Above: number size distribution from Princess Street, Manchester

14 Is PM 10 the right metric? Below: spatial variability in ultrafine particle concentration in a district of Manchester

15 Fixed monitor data does not characterise exposure

16 Ultrafine particle (UFP) exposure diary

17 Commuting exposure to UFP Mean 10 x residential, 30% of daily dose in 5% of time, 100% of >100 000 cm -3

18 Typical bus commute exposure to UFP

19 Elements of example bus commute exposure to UFP Suburban indoors = 6 000 cm-3 Central indoors = 4 000 cm-3 Suburban outdoors = 11 000 cm-3 Central outdoors = 20–40 000 cm-3 On-bus = 50–100 000 cm-3 peaks = up to 400 000 cm-3 BUS concentrations 10 – 20 times INDOORS PEAK concentrations up to 100 times INDOORS Our AIM is to understand what controls EACH of these segments

20 CityFlux NERC 2004-7 investigating the transport and chemical transformation of pollutants (gases and aerosols) in urban areas, through measurements at three spatial scales: Individual plumes Street canyons Emission from an urban area

21 Oxford Road, Manchester (2006) 3 800 scheduled bus movements per day Every 14 seconds in daytime (Mon-Fri)

22 CO concentrations at Oxford Road northbound bus stops (Mon-Fri 7am – midnight)

23 CO and particles at Oxford Road Are particles formed or transformed within the canyon space? Above: TOF-AMS Below: DMPS, PTR- MS and CO

24 CityFlux: emission from the city centre (2005,6) Regular emission cycles Sheltering, recirculation, deposition, thermal stability & inversions Total particle number Particles 50 nm < D p < 32 m in 100+ size bins CO 2, H 2 O AMS fluxes (with CEH Edinburgh) VOC (PTR-MS, Univ. Lancaster ) Flux

25 CityFlux: emission from the city centre

26 Urban canopy particle turbulent ventilation fluxes All data from NERC CityFlux project, Manchester Above: fluxes Below: concentrations

27 Questions we will address in analysis Do urban street canyons act as reaction chambers? How does the amount and composition of the particles we breathe depend upon meteorology? At what rates are particles emitted by urban processes and formed in the urban atmosphere? What do Manchester (and other cities) add to the regional and global atmosphere?

28 To be continued… Thanks for your attention

29 Urban air is cleaner than it was – isn’t it?

30 What PM 10 levels do we experience? 1999-2005 Means: Piccadilly 27 Eccles 23 Stockport 22


Download ppt "Pollution levels plummet in clean air fight (but…) Ian Longley School of Earth, Atmospheric & Environmental Sciences University of Manchester."

Similar presentations


Ads by Google