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Esmeralda an inter regional mapping and
forecasting background air quality system
Chimere Workshop
Paris, the 21 and 22 of March
Mireille LATTUATI, Paris
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ESMERALDA project Context

• Objectives
• a new tool for monitoring air quality
• a tool for studies at the local and regional
  scales
• ex atmospheric action plans PPA, PRQA
• ? a common tool for modelling and forecasting air
  quality
• a better description of the phenomenom of
  pollution at a regional scale and a cost
  effectiveness

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ESMERALDA project context

• the Chimere model operationnal since 2000 in the
  Ile de France region
• a strong partnership with the CNRS and the
  availability of the Chimere multi scales model
• an uptaded emission inventory (2000)
• the availability of the national forecasting
  system PrevAir
• ? the extension of the regional system to a
  larger domain

The patners
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Esmeralda system in short

• TCM Chimere multi scales model
• Meteorological forecasts NCEP/AVN MM5
• Boundary conditions PrevAir
• Emissions inter regional emissions (2000
  current traffic)
• Grid 441 x 468 km2
• with 6 km grid size
• Running time (gas version) 2 h for Chimere 2
  h 30 for MM5
• (PC Linux Dell PowerEdge 2600- bi processor Xéon
  3 GHtz)

? Esmeralda domain

• fall 2003 patnership

• summer 2004 1st operationnal version
• for the forecast of O3 and NO2 concentrations for
  the day before, the same day and the 2 following
  days

• summer 2005 aerosol version

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Operational design
TCM
Air quality maps and forecasts O3 and NO2
forecasts from D-1 to D2 and Air quality
index for D-1 and D0
Meteorological forecasts NCEP MM5 (US) from
D-1 to D2

Source Ineris - Prevair
Boundaries Conditions from the meso scale model
Chimere PREVAIR
Near real time (D-1) and estimated (D,D1,D2)
hourly emissions CO, NO, NO2, CH4 and 11
COVNM
Air quality observed data NO2, O3, PM10 and SO2
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Emission modelling
Traffic emissions
30 minutes
Traffic data
A near real time modelling system from traffic
data acquisition to AQ modelling
operationnal since 2003
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Emissions maps NOx
Emissions density kg/inhab.
Emissions density t/km2/year
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Emissions maps COV
Emissions density t/km2/year
Emissions density kg/inhab.
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Meteorological forecasts

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Meteorological forecasts

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Background air quality forecasts
A daily inter regional description for NO2 and O3
NO2 daily max
O3 daily maximum
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Background air quality assesment
An approach based on a combinaison of in-situ
measurements and model outputs to provide a more
accurate description of the air pollution
patterns
Geostatistical method (using Isatis software)
monitoring networks
mixing observed data, SO2 and PM10 emissions and
O3 and NO2 CHIMERE model outputs
AQ Index
Chimere output O3 max concentrations
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The Air Quality Index

• The Air quality index (ATMO index)
• based on 4 main pollutants (SO2, NO2, O3, PM10)
• the worst of the 4 pollutants
• a figure going from 1 (very good) to 10 (very
  bad)

• AQ index maps uptaded twice a day (D-1 and
  D0)

? AQ index 16th of march
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The Air Quality Index
showing the  contrasted  influence of the
pollutants
O3
NO2
PM10
SO2
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Daily forecasts operationnal results
Period summer 2004 Pollutant O3
J1
J0
Champagne
Ile de
Champagne
Ile de
Centre
Picardie
Picardie
Ardenne
France
Ardenne
France
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Niveaux d'information
3
2
7
2
2
7
Taux de bonne détection avec
33
0
85
0
50
85
0
une marge de 10
Taux de fausse alerte avec
33
0
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50
0
33
0
une erreur supérieure à 10
Good predictions rate number of observed and
forecasted episods nb of observed episods
False alarms rate number of forecasted and non
observed episods number of forecasted episods
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Daily forecasts O3 pollution episod
29th of july to 3rd of august
Information threshold
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Daily forecasts O3 false alarm
the 5th of august a false alarm
the 4 of august
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Daily forecasts statistical results
period 1st of june to 31st of septembre
2004 pollutant O3
E30 (E30/100) is the of errors less than 30
ug/m3 in absolute value (when observation is
greater than 100 ug/m3) A positive bias
indicates that the model is underestimating on
average.
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Daily forecasts statistical results
Biais (ug/m3)
Summer 2004, D0, O3
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Daily forecasts statistical results
Root mean square (ug/m3)
Summer 2004, D0, O3
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Daily forecasts statistical results
Correlation
Summer 2004, D0, O3
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Case study related to background AQ
Work in progress an attempt in combining AQ
concentrations with population to provide
information on exposure
Number of people exposed to concentrations
exceeding the information thresholds
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Exposure
Example of September 19th, 2003 pollution
episode (O3 and NO2)
386 983 people are exposed to O3 concentrations
exceeding 180 µg/m3
? O3 concentrations at 5 pm
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Esmeralda web side
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Thank you for your attention