Natividad Urquizo, W. Pugsley, D. Spitzer* & M. Robinson City of Ottawa *A-MAPS Environmental Mapping Small Scale Air Pollution Distribution using Satellite Observations in a Large Canadian City

2 Project Location

3 l Using satellite data map pollution concentrations for 5,600 km 2 area. l Identify hot spots spatially at 1-km 2 resolution hour by hour for the following air contaminants: l Nitrogen oxides (NO, NO 2, NOx) l Carbon monoxide l Ground level ozone l PM 2.5 Objectives

4 Data sources l Ground level air quality monitors l NAPS permanent stations (3) l One Quebec station (PM 2.5 & O 3 ) l Mobile labs for 8 locations l Aura satellite data (13 x 24 km resolution) l Air and ground transportation data l Meteorological data l Land use data l Data processing by A-MAPS Environmental Inc.

5 Ground Level Monitoring Locations

6 Total Mapping Area

7 Data Integration l Time of satellite overpass: l Determine grid point value at the centre of each satellite pixel l Used Kriging to interpolate with 1-km 2 l Smooth ground data with 3-hour running average l Calculate field ratio of ground level measurement to satellite l Calibrate pixel with spatial average of field ratio

8 Data Integration … continue l Calculate hourly concentrations from interpolation in time using closest ground station l Modify values using traffic emissions and the Green function, advection and diffusion equations l Finally calibrate 1-km values from measured concentration at nearest emission source

9 Confirm previous findings l Pollutants below hourly Canada Wide Standards 95% of the time l Pollution is locally produced and result of trans-boundary pollution l Smog events not restricted to summer days (December th ) l Major roads exhibit more pollution at peak hour

10 High Pollution Nodes

11 Transportation Impact on NO 2 Exceedances NO 2 > 50ppb

12 New Findings: NO 2 west-east gradient

13 O 3 : West-East Gradient

14 PM 2.5 : west-east gradient

15 More new findings l Origin of worst episodes: l From the east (Montreal, Sept 14 th ) l From the south (Ohio Valley, Sep 21 st & 25 th ) l Locally produced (Dec 13 th )

16 September 14 th 2007 Episode Montreal Influence

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37 Confidence level PollutantSTD (Map)STD (MOE) CO (ppm) – 0.14 NO (ppb) – 8.74 NO 2 (ppb) – 11.5 NO x (ppb) – 17.5 O 3 (ppb) – PM 2.5 (ug/m 3 )65.84 – 6.75

38 Single pixel comparison l Orleans site measurements using mobile lab and results of modelling shows good cross- validation PollutantSTD CO (ppm) NO 2.4 (ppb) NO (ppb) NO x 4.4 (ppb) O3O3 3.8 (ppb) PM (ug/m 3 )

39 Downtown NOx concentrations l Peak hour pollution lasts 4 hours or less l Three-hour running average smoothes traffic effect

40 Relative Exposure Concentration of PM and Influence of traffic Krzyzanowski et al (2005) Relative Exposure Concentration of PM and Influence of traffic Krzyzanowski et al (2005) l Shows 24 hour traffic generated exposure for PM2.5 l Light pink: regional background, light blue: urban ambient and peaks in traffic l Exposure while commuting represents half of exposure to PM from traffic

41 Major Origin-Destination Flows – Morning Trips 2005 Ref:

42 NO2 hourly un-smooth maps

43 NO2 October 4 th, 2007 at 2 h

44 NO2 October 4 th, 2007 at 3 h

45 NO2 October 4 th, 2007 at 4 h

46 NO2 October 4 th, 2007 at 5 h

47 NO2 October 4 th, 2007 at 6 h

48 NO2 October 4 th, 2007 at 7 h

49 NO2 October 4 th, 2007 at 8 h

50 NO2 October 4 th, 2007 at 9 h

51 NO2 October 4 th, 2007 at 10 h

52 NO2 October 4 th, 2007 at 11 h

53 NO2 October 4 th, 2007 at 12 h

54 NO2 October 4 th, 2007 at 13 h

55 NO2 October 4 th, 2007 at 14 h

56 NO2 October 4 th, 2007 at 15 h

57 NO2 October 4 th, 2007 at 16 h

58 NO2 October 4 th, 2007 at 17 h

59 NO2 October 4 th, 2007 at 18 h

60 NO2 October 4 th, 2007 at 19 h

61 NO2 October 4 th, 2007 at 20 h

62 NO2 October 4 th, 2007 at 21 h

63 NO2 October 4 th, 2007 at 22 h

64 NO2 October 4 th, 2007 at 23 h

65 NO2 October 5 th, 2007 at 0 h

66 Public Health Policy Challenges l Answers required: l What sort of spatial accuracy and temporal frequency for air pollutant concentrations is needed to comply with public health requirements? l What response or action is needed at urban hotspots for short duration high intensity events or for extended events? l What threshold for each pollutant should be established as a trigger for corrective action?

67 Technical Breach Areas – City of York l Sample of roads with pollution above standard l Ottawa/Gatineau exhibit similar hot spots during peak hours l Future AQ modelling at neighbourhood level

68 Acknowledgements l This mapping project was possible with funding from: l GeoConnections (Natural Resource Canada) l The Ottawa International Airport l The City of Ottawa l In kind contributions from: l Transport Canada l Environment Canada l Ontario Ministry of the Environment (MOE) l Ministère du Développement durable, de l'Environnement et des Parcs (of the province of Quebec) and l Health Canada l A-MAPS Environmental was contracted for this project

69 Contact information: l Natividad Urquizo x