SEIG seminar 2014 - A Smarter Way to Lower Emissions - Stephen Stratton

© Ricardo-AEA Ltd

www.ricardo-aea.com

Assessing variations in roadside air quality with sampling height21st October 2014

© Ricardo-AEA LtdRicardo-AEA in Confidence2

Introduction

2

• Study commissioned by the Scottish Government to investigate roadside air quality versus height.

• Progress so far.

• Some results (still provisional).


The Study

3

“The study will investigate how Air Quality varies with height and aims to:

•Determine the relationship between height from pavement and Air Quality.

•Investigate the relationship between mobile and fixed sampling methods.

•Examine diurnal and seasonal variations in Air Quality.

The outputs will help inform Air Quality policy in Scotland.”


The Team

Ellis Marshall-Padkin

Stephen Stratton

Susannah Telfer Stephen Gray

David Hector

Sam Copsey Brian Stacey

Stuart Sneddon


The Equipment

Species Sampling Method/Analyser

PM2.5 (Automatic) Lighthouse IAQ 3016 PM2.5analyser

PM2.5 (Gravimetric) Harvard-PEMS + BGI pump (Personal Exposure Monitor)

Black Carbon Magee MicroAeth AE51Ultrafine Particles Philips NanotracerNO2, SO2, CO and O3 AQMeshCO2 COZIR Optical SensorBenzene Pumped tube sampling

Meteorology Lufft WS600 (WS+WD+T+H+P+RF)

Video and GPS RoadhawkData Acquisition Weblogger with 3G telemetry


The Location – Why Glasgow?

• Glasgow is Scotland’s largest city.

• Glasgow City Centre combines a variety of urban environments within walking distance.

• Glasgow City Centre is busy, both in terms of road traffic and people.

• Ricardo-AEA Scotland office, Blythswood Square.


So Far…

• Literature Review

• Testing

• Co-locations

• Sampling Runs


Findings - Literature Review

• No study was found that incorporated mobile sampling with sampling at more than one height.

• The review focussed on but was not restricted to the following types of study:

Ø Air quality versus height.

Ø Mobile monitoring.

Ø Personal exposure.

• Research indicates that a pollutant gradient does exist at heights below 3 m above ground level, but that the following factors will affect the vertical profile:

Ø Meteorology.

Ø Topography.

Ø Distance from emissions source.

• Methodology outlined for the study was validated.

• Sampling heights defined as 168 cm above ground level for the average height of an adult above the age of 16 years in Scotland; and 80 cm for a child in a buggy.

• Highlighted problems that we might encounter.


Sampling Regime

• Predetermined route.

• 8 mobile sampling exercise (2 weekend days).

• 6 co-location exercises, sampling at an automatic monitoring site.

• Carried out between February and August 2014.


Sampling Route

Map data ©2013 Google

Street name Description of street on route

Approximate Length of street

within study route (miles)

Hope Street Busy urban canyon orientation south to north (partially restricted to buses and taxes)

0.42

Sauchiehall Street Urban pedestrian precinct orientation west to east 0.16

Buchanan Street Urban pedestrian precinct orientation north to south 0.22

St Vincent Street Busy urban canyon orientation west to east 0.10George Square Busy urban street orientation west to east 0.14George Street Busy urban canyon orientation west to east 0.14

Montrose street Busy urban canyon orientation north to south 0.11

Ingram Street Busy urban street orientation west to east 0.18High street Busy urban street orientation north to south 0.21Saltmarket Busy urban street orientation north to south 0.34

Clyde Street/Broomielaw Busy Urban street orientation east to west 0.44

Oswald Street Busy urban street orientation north to south 0.16

Ricardo-AEA Office


• 185 miles covered and 9,840 ft “climbed”……over a total of 82 hours.• 2 x 18,575 Calories used.

Vital Stats

11

Mobile Sampling Exercises

Fri 14/03/2014

Thur 10/04/2014Wed 21/05/2014Mon 23/06/2014Tue 08/07/2014Sun 13/07/2014Sat 09/08/2014Fri 15/08/2014

Colocation Exercises

Townhead AURN (including BC) 14/02/2014

Hope Street AURN 25/04/2014



Hope Street 13/08/2014

London Marylebone Road (UFP only) 21/08/2014

Townhead AURN (including BC) 27/08/2014


PM2.5 (µg m-3)

Contains Ordinance Survey data © Crown copyright and database right 2014.


Black Carbon (ng m-3)



Ultrafine Particles (N Particles cm-3)



NO2 (µg m-3)



Results – Correlations (Normalised)

NH_UFP

NH

_BC

0.10

0.15

0.20

0.25

0.30

0.00 0.05 0.10

NH_BC=1.5[NH_UFP]+0.07 R2=0.62

NH_UFP N

H_P

M2.

5

0.0

0.1

0.2

0.3

0.00 0.05 0.10

NH_BC

NH

_PM

2.5

0.0

0.1

0.2

0.3

0.10 0.15 0.20 0.25 0.30

NH_BC

NH

_NO 2

0.2

0.3

0.4

0.5

0.10 0.15 0.20 0.25 0.30

NH_UFP

NH

_NO 2

0.2

0.3

0.4

0.5

0.00 0.02 0.04 0.06 0.08

NH_PM2.5

NH

_NO 2

0.2

0.3

0.4

0.5

0.1 0.2 0.3


Results – PM vs Height

Pollutant LOW/HIGH DifferencePM0.5 ~0%PM1 ~0%PM2.5 ~0%PM5 ~7%PM10 ~12%Black Carbon ~5%UFP ~0%NO2 ~0%

• Latest analyses indicate that a concentration gradient does exist:


Results – Diurnal/Seasonal Variations

Wednesday, 21/05/2014

H_U

FP, H

_BC

, H_P

M 2.5

, H_N

O 2

20000

25000

30000

H_U

FP

20002500300035004000

H_B

C

56789

10

H_P

M 2.5

40506070

08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00

H_N

O 2

H_UFP H_BC H_PM2.5 H_NO2

Thursday, 10/04/2014

H_U

FP, H

_BC

, H_P

M 2.5

, H_N

O 2 20000

25000

30000

H_U

FP

20002500300035004000

H_B

C

810121416

H_P

M 2.5

4045505560

08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00

H_N

O 2


Friday, 14/03/2014

H_U

FP, H

_BC

, H_P

M 2.5

, H_N

O 2

150002000025000

H_U

FP

200030004000500060007000

H_B

C

10203040

H_P

M 2.5

303540455055

08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00

H_N

O2


Sunday, 13/07/2014

H_U

FP, H

_BC

, H_P

M 2.5

, H_N

O 2

1500020000

25000

H_U

FP

150020002500300035004000

H_B

C

468

H_P

M 2.5

20

3040

09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00

H_N

O2



Results – Diurnal/Seasonal Variations

Thursday, 10/04/2014

NO2 (ppb)

Freq

uenc

y

0 20 40 60 80 100 120 140

050

100

150

Friday, 14/03/2014

NO2 (ppb)

Freq

uenc

y

0 50 100

050

100

150

200

Wednesday, 21/05/2014

NO2 (ppb)

Freq

uenc

y

0 50 100 150 200

050

100

150

200

Sunday, 13/07/2014

NO2 (ppb)

Freq

uenc

y

0 50 100

020

4060

8010

0


Finally…

• This type study, combining mobile monitoring with monitoring at more than one height, has not been carried out before.

• Collected a lot of data!

• Ongoing analyses indicate that a concentration gradient does exist, but that it is pollutant dependent and changes with microenvironment.

• ‘Typical’ diurnal variations in pollutant concentrations are seen.

• Method has proved very useful for characterising the spatial distribution of pollutants, identifying pollution ‘hotspots’.

• Final results due to be published by the end of 2014…

© Ricardo-AEA Ltd

www.ricardo-aea.com

T:E: W:

Stephen Stratton

+44 (0)1235 75 [email protected]

Comments/ Questions?

SEIG seminar 2014 - A Smarter Way to Lower Emissions - Stephen Stratton

Environment

ricardoaea ltdricardoaea

ricardoaea scotland

sampling heights

mobile sampling exercise

incorporated mobile

roadside air quality

air quality policy

fixed sampling methods