Developments in ADMS-Urban and ADMS-Roads including new road traffic emission factors

Transcription

1 Developments in ADMS-Urban and ADMS-Roads including new road traffic emission factors David Carruthers User Group Meeting Vilnius March 2013

2 Contents New emissions in ADMS-Urban and ADMS-Roads 3.1 Background How do the new emission factors compare to the old? New EFT v5.1 in ADMS-Urban and ADMS-Roads Modelling NO 2 using the EFT factors Upcoming model developments Urban flows and canyons Nesting ADMS-Urban in regional models Taking account of time history of emissions within plume Other model enhancements Mapper Links to Google Earth Model speed-up

3 New emissions in ADMS-Urban and ADMS-Roads 3.1 Background UK Emission Factor Toolkit factors included in ADMS-Urban and ADMS-Roads Current update to EFT includes: NO x emission factors: COPERT IV European speed emission curves (year independent) Mileage degradation factors (year dependent) PM emission factors: Includes exhaust, brake wear, tyre wear and road abrasion Still no inclusion of resuspension factors New fleet data, with factors for: London, England, Scotland, Wales and Northern Ireland How applicable are these to the Baltic states?

4 New emissions in ADMS-Urban and ADMS-Roads 3.1 How do the new emission factors compare to the old? Tables taken from the LAQM Support Helpdesk Advice Note EFT Urban driving: All factors higher Diesel LDVs much higher Motorway driving: Diesel LDVs much higher Decreases for HDVs Year

5 % change % increase New emissions in ADMS-Urban and ADMS-Roads 3.1 How do the new emission factors compare to the old? Consider emissions for a road with a typical fleet mix, for 2010, 2015, 2020 Typical fleet mix Increase in NO x & PM 10 estimates Motorcycles Cars LGVs Buses/coaches HGVs 60 Petrol car Diesel car

6 New emissions in ADMS-Urban and ADMS-Roads 3.1 New EFT v5.1 in ADMS-Urban and ADMS-Roads 4 new emission factor datasets Light duty vehicle Heavy duty vehicle New datasets: EFT v5.1 (#Vehicle Categories) EFT v5.1 (2 VC) EFT v5.1 (6 VC) EFT v5.1 (7 VC) EFT v5.1 (8 VC) Car Diesel car Petrol car LGV Taxi Motorcycle HGV Rigid HGV Articulated HGV Bus and coach

7 New emissions in ADMS-Urban and ADMS-Roads 3.1 New EFT v5.1 in ADMS-Urban and ADMS-Roads Each dataset is categorised by region London (central) London (inner) London (outer) Other changes New region types London England Scotland Wales Northern Ireland Urban Rural Motorway New dataset (EFT v5.1) Old dataset (EFT v4.2) Year ranges Speed range (km/hr)

8 New emissions in ADMS-Urban and ADMS-Roads 3.1 Modelling NO 2 using the EFT factors New primary NO 2 estimates have been published alongside the new emission factors (NAEI Data Warehouse download spreadsheet and Advice note). Primary NO 2 by vehicle type (2015) Percentage of NO x that is NO 2

9 New emissions in ADMS-Urban and ADMS-Roads 3.1 Modelling NO 2 using the EFT factors New primary NO 2 estimates have been published alongside the new emission factors (NAEI Data Warehouse download spreadsheet and Advice note). Primary NO 2 for all traffic Percentage of NO x that is NO 2 Year

10 New emissions in ADMS-Urban and ADMS-Roads 3.1 Modelling NO 2 using the EFT factors New primary NO 2 estimates have been published alongside the new emission factors (NAEI Data Warehouse download spreadsheet and Advice note). Section in the User Guide (p32) gives the steps required to include primary NO 2 emissions in your model run (via Emissions Inventory database).

11 Upcoming model developments

12 Upcoming model developments Urban Flows and Canyons Improve the modelling of the important physical processes in urban (and also industrial) environments

13 Modelled NO x concentration (µg/m 3 ) Upcoming model developments Urban Flows and Canyons London Model Inter-comparison Study: Annual Average NO x 500 ADMS-Urban ADMS-Urban Queue BRUTAL 500 Kerbside Roadside ERG toolkit CMAQ-urban PCM Suburban Urban Background 500 Measured NO x concentration (µg/m 3 ) 500

14 Upcoming model developments Urban Flows and Canyons NO 2 pollution roses for Marylebone Road 2008: ADMS calculated Monitored Bivariate polar plot of NO 2 concentration at Marylebone Road: Wind speed on radial axis Concentration shown by colour Road width 22m, canyon height 20m Shows that models predict high concentrations for low wind speeds in all directions Effect of street canyon shown in measured data plot

15 Upcoming model developments Urban Flows and Canyons Prevailing wind U o OSPM approach Wind side Recirculation region Lee side Building height H B Building height H B Canyon width L

16 Upcoming model developments Urban Flows and Canyons OSPM approach Well mixed recirculating region No channelling of flow along canyon Flow/turbulence within canyon has little dependence on H B and L Wind side Not possible to consider pavements or road lanes Not formulated for one-sided or asymmetric canyons Recirculation zone U o Lee side

17 Upcoming model developments: Urban Flows and Canyons Flow through widely separated buildings b g ΔU w θ U o

18 Upcoming model developments: Urban Flows and Canyons Flows with wake attached to downstream building Domain D m mean streamline b g wakes attach ΔV 1 U o θ street 1 street 2

19 Upcoming model developments: Urban Flows and Canyons Flow through closely packed aligned buildings mean vertical profile of wind speed U m z U o V m U m + ΔU m U o ΔU m U component in x direction

20 z/h z/h Upcoming model developments: Urban Flows and Canyons Velocity profiles in and above urban canopy U H U o b g U C Velocity profile Turbulence profile

21 Upcoming model developments Urban Flows and Canyons New canyon/urban street model Well mixed recirculating region Flow/turbulence within canyon has dependence on height and width; allows for high aspect ratio Can consider pavements and road lanes One-sided/asymmetric canyons source m th street plume centrelines m+1 th street g Channelling of flow along canyon

22 Upcoming model developments Urban Flows and Canyons Dispersion definition of sources Different sources with weighting depending on porosity, h, g and angle of wind to road. volume source at end of canyon source at canyon top ground level source buildings recirculation pavement perpendicular parallel road in canyon buildings q1 - ground level line source in street with flow parallel to street q2 - ground level line source along street with flow perpendicular to street q3 - constant concentration in canyon (recirculating flow) q4 - ground level line source along street with flow parallel to upstream wind q5 elevated line source parallel to street at height of buildings with flow parallel to upstream wind. q6 - volume source at end of street with flow parallel to upstream wind

23 Nesting local model (ADMS-Urban) within regional model: motivation Why nest a local model within a regional model? What are the advantages of a nested model? Model feature Model Regional (eg grid based) Local (eg Gaussian plume) Domain extent Country (few 1000 km) City (50km) Meteorology Dispersion in low wind speed conditions Deposition and chemical processes Spatially and temporally varying from meso scale models Models stagnated flows correctly Reactions over large spatial and temporal scales Usually spatially homogeneous Limited modelling of stagnated flows Simplified reactions over short-time scales Source resolution Low High Validity Background receptors Background, roadside and kerbside receptors

24 13 Sep 99 3:00pm Level one O3 NO O3 NO NO2 NO2 VOC VOC HKUST CMAQ/CAMx Modelling for Hong Kong; ADMS-Urban to be nested within this

25 Nesting - Example of Preliminary Model results: NO 2 average contours (CMAQ) CMAQ outer domain 9km NO 2 µg/m³ Consistency of background concentrations ADMS-Urban nested domain 1km

26 Upcoming model developments Emission history 1 Concentration due to emissions in current hour Concentration due to emissions in previous hour source wind speed, U U x 1 hour U x 2 hours

27 Emission Factor Upcoming model developments Emission history 2 Central London road NOx emission factors Rapid increase in emissions at rush hour Weekday Saturday Sunday Hour source wind speed, U U x 1 hour U x 2 hours

28 Other model developments - Impacts of cuttings, embankments, tunnels and flyovers

29 Other model developments - Improvement to initial mixing height estimate Improvement to initial mixing height estimate Currently 1m for all vehicles and at all speeds May have a significant effect on ground level concentrations Equal to source height at low speeds Related to vehicle height at high speeds due to traffic induced turbulence Fast traffic speeds Slow traffic speeds

30 Other model enhancements

31 Visualisation I Link to ADMS Mapper Currently implemented in ADMS 4/5 View sources, buildings, specified output points and the output grid Add, move, edit and delete sources and specified points Define the output grid Display concentration contours (plots created independently or using Surfer or Spatial Analyst) Other GIS functionality (for example view background maps, use measuring tool, modify layer features, display feature names, export in different formats)

32 Visualisation II ADMS Mapper

33 Visualisation III ADMS Mapper

34 Visualisation IV Mapper link to Google Earth Google Earth visualisation

35 Speed up code General speed up in next release due to code improvements; significant speed up for complex terrain module calculations Take advantage of multiprocessor machines: Split up model runs: different meteorology, and/or different model domains Managed by Run Manager

36 Summary New emissions in ADMS-Urban and ADMS-Roads 3.1 Background How do the new emission factors compare to the old? New EFT v5.1 in ADMS-Urban and ADMS-Roads Modelling NO 2 using the EFT factors Upcoming model developments Urban flows and canyons Nesting ADMS-Urban in regional models Taking account of time history of emissions within plume Other model enhancements Mapper Links to Google Earth Model speed-up