dispersion modelling work at king’s college london
DESCRIPTION
Dispersion modelling work at King’s College London. David Carslaw Environmental Research Group King’s College London. London Air Quality Network-LAQN. Insight from measurements. Secondary pollutants from UK/Europe Natural particle episodes e.g. Saharan dust in March 2000 - PowerPoint PPT PresentationTRANSCRIPT
Dispersion modelling work at King’s College London
David Carslaw
Environmental Research Group
King’s College London
London Air Quality Network-LAQN
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Insight from measurements– Secondary
pollutants from UK/Europe
– Natural particle episodes e.g. Saharan dust in March 2000
– Very localised conditions e.g. congested traffic and the specific configuration of buildings 0
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14-Feb-03 16-Feb-03 18-Feb-03 20-Feb-03 22-Feb-03 24-Feb-03 26-Feb-03 28-Feb-03
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Particle episode, February 2003
Model development
• Data from LAQN has been used in the development of practical models for London– NO2 and PM10 regression and receptor models
(Carslaw et al., 2001; Fuller et al., 2002)– Techniques used in tandem with ADMS to
predict concentrations London-wide
Carslaw, D.C., Beevers, S.D., Fuller, G., 2001. An Empirical Approach for the Prediction of Annual Mean Nitrogen Dioxide Concentrations in London. Atmospheric Environment, Vol. 35, 1505-1515.
Fuller, G.W., Carslaw, D.C., Lodge, H.W., 2002. An Empirical Approach for the Prediction of Daily Mean PM10 Concentrations. Atmospheric Environment, Vol. 36, 1431-1441.
Met pre-processors• Some account has been
taken of urban meteorology based on parameterisations in the literature– Addition of anthropogenic
heat flux
– Approach is too simplistic
– Need for more appropriate met data for urban modelling (heat fluxes, energy balances)
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Application of dispersion models in London
• Projections of future base case concentrations of NO2 and PM10
• Analysis of the efficacy of different potential policies in London e.g. a low emission zone and the use of new vehicle technologies
Congestion charging (CCS)
• ERG will be working with Transport for London to monitor the CCS scheme (AQ measurement, emissions, prediction)
• It will provide an unprecedented level of traffic activity information– Continuous traffic counters– Manual counts – specific
vehicle types– Automatic number plate
recognition (ANPR)
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Congestion charging
• Many interesting research questions:• CCS is a large natural experiment i.e. the effect of a
perturbation
• How atmospheric composition responds to a specific policy in a large urban area
• Potential effects of displacing emissions to hours of the day where dispersion is less efficient
• How secondary pollutants respond to emissions changes over a comparatively small area
• Re-suspended particulate matter from vehicle-induced turbulence
Research priorities
• Urban meteorology– Significantly more information is required
• Connecting the different scales– No one model works at all scales
• Developments in dispersion modelling needs to be matched with developments in emissions inventories– Emission factors, spatial and temporal scales, species
considered– A wider context: urban morphology, heat release etc.– Data management e.g. expertise with GIS