passive pollution barriers: hedges and trees in open ... › civileng ›...

1www.surrey.ac.uk/gcareThursday, 21/07/2017 1www.surrey.ac.uk/gcareApril 2019 @pk_shishodia @AirPollSurrey © Prof P Kumar

Professor Prashant KumarChair in Air Quality and Health

Founding Director, Global Centre for Clean Air Research (GCARE) Department of Civil & Environmental Engineering

University of Surrey, United Kingdom---------

Adjunct Professor, Trinity College Dublin, Ireland---------

PASSIVE POLLUTION BARRIERS:HEDGES AND TREES IN OPEN-ROADSIDE ENVIRONMENTS

Green Infrastructure Webinar 24 April 2019

@AirPollSurrey @pk_shishodia


GCARE: Team & Research

Green Infrastructure - Measurements & Modelling

Research to Guidance- City Hall (Mayor of London)

Outline

3www.surrey.ac.uk/gcareThursday, 21/07/2017 3www.surrey.ac.uk/gcareThursday, 24 August 2017surrey.ac.uk/gcare

GCARE….thanks to team/collaborators

‘to realise a collaborative global vision of ‘clean air for all’

@AirPollSurrey @pk_shishodia

GCARE team


Acknowledgements..Thanks to our research sponsors, GCARE team and research collaborators…

The iSCAPE & OPERANDUM projects have received funding from the

European Union’s Horizon 2020 programme under grant agreement Nos.

689954 & 776848, respectively.

ASAP-Delhi is a UK-India project funded under the NERC-MRC-MoES-DBT

programme on Atmospheric Pollution and Human Health in an Indian Megacity

CArE-Cities Clean Air Engineering for Cities INHALE Project

Pollution Guardian & GlobalHOM


Exposure Control methods

ACTIVE PASSIVE

Source control

e.g. exhaust emissions;

combustion sources

Receptor control

masks, de-routing…

BTW Source-receptor

green barriers, LBW, photocatalytic coating


Source: Eisenman…Kumar et al. (2019). Urban trees, air quality, and asthma: An interdisciplinary review. Landscape and Urban Planning 187, 47-59.

• Green infrastructure is good and we all love it, but there are also downsides• Important to choose what and where to place?• Local scale can act as a passive barrier between source and receptor (appreciable decrease )• City scale air quality (much less compared with local scale)

Greening – how it works?


Green roofGreen roof

Built-up street canyon configurations

Figure 1

(a)

(b)

(c)

(d)

Gre

en

wa

ll

Gre

en

wa

ll

Leeward windward

Leeward windward

Leeward windward

Leeward windward

Road with vegetation barrier

Road with green wall

Open road configurations

Wind flow

Wind flow

Wind flow

Road with no vegetation barrier(a)

(b)

(c)

Figure 2

Abhijith, Kumar et al., 2017. Atmospheric Environment 162, 71-86.

Greening – street v/s open roads


Abhijith and Kumar, 2019. Atmospheric Environment 162, 71-86; City Hall Guidance, 2019

Greening – concentration decay

Concentration decay

Road with vegetation barrier

Road with green wall

Open road configurations

Wind flow

Wind flow

Wind flow

Road with no vegetation barrier(a)

(b)

(c)

Figure 2

Distance from road

Wind direction

Dispersion (re-distribution) => Dilution + Deposition

Efficacy increases with an decrease in porosity; more effective closer to source

H


Open-road green barriers

Started by curiosity… near real-time measurements of particle size distributions

Al-Dabbous & Kumar, 2014. Atmospheric Environment 90, 113-124.


DMS50 & pseudo-simultaneous measurements using 4-way solenoid switching system

①

- Battery +

- Battery +Laptop

⑥

⑤

- Battery +

DMS50

②

③

④

Switching

system

① Analog cable

② USB connection

③ Ethernal connection

④⑤ Tube

⑥ Electrical wiring

❶❷

❸❹

Sampling locations

1

2 3 4

Open-road green barriers

Vegetation barrier found to reduce PNCs by ∼37% during the cross-road winds.

Al-Dabbous & Kumar, 2014. Atmospheric Environment 90, 113-124.


Improving the Smart Control of Air Pollution in Europe

Website: https://www.iscapeproject.eu/

https://www.iscapeproject.eu/


Green barriers (iSCAPE project)

visit: https://www.iscapeproject.eu/

https://www.iscapeproject.eu/


9 m

13 m11 m

1.5 m

7 m

3

(d) TOA

1.5 m 1.2 m

(a) HON

1 m

7 m3 m

1.5 m

10 m

(c) TON

1 m

7 m6 m

1.5 m 2 m

(b) HOA

7 m4.5 m

1.2 m

1.5 m

4 m

(e) THN3.5

7 m5 m

7 m

9 m

1.5 m

5m

(f) THA

7 m

Near-road scenario (<1m) Far-road scenario (>2m)

*Figures are not in scale

Instruments on tripod

Guildford field campaign

Measuring point behind vegetation Measuring point In front of vegetation

RoadFootpath Unpaved earth or grass Abhijith & Kumar, 2019. Atmospheric Environment 201, 132-147.


Average ∆pollutant concentration : Along-road>Cross-road>Cross-Vegetation

Guildford field campaign

Abhijith & Kumar, 2019. Atmospheric Environment 201, 132-147.


GI treatment in dispersion models

How can GI be considered in readily available dispersion models to allow evaluation of its impacts on pollutant concentrations and health risk assessment?

Tiwari, Kumar et al., 2019. Science of The Total Environment 672, 410-426.

16www.surrey.ac.uk/gcareThursday, 21/07/2017 16www.surrey.ac.uk/gcareApril 2019 @pk_shishodia @AirPollSurrey © Prof P Kumar16

Trees Tree + HedgeHedge

Open Road

Passive solutions

Abhijith & Kumar, 2019. Atmospheric Environment 201, 132-147.


City Hall Guidance on the use of GI

Available from:https://www.london.gov.uk/WHAT-WE-DO/environment/environment-publications/using-green-infrastructure-protect-people-air-pollution

Covers both street and open-road conditions

https://www.london.gov.uk/WHAT-WE-DO/environment/environment-publications/using-green-infrastructure-protect-people-air-pollution

https://www.london.gov.uk/WHAT-WE-DO/environment/environment-publications/using-green-infrastructure-protect-people-air-pollution


Thank you!

Contact: Professor Prashant KumarEmail: [email protected]

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