A European model-intercomparison studyin support to the CAFE programme

on EU environmental legislation

organised by

JRC-IES (coordinator), IIASA, EMEP, EUROTRAC / TNO-MEP

C. Cuvelier, P. Thunis, L. Tarrason, M. Amann

ObjectiveObjective

To explore changes in air-quality (DELTA) in cities (CITY) due to changes in emission as predicted by atmospheric models with different scales

Deltas between: • Models• Cities• Scenarios• Scale

FocusFocus

Integrated assessment of the impact on human health and ecosystems. WHO recommendations: Long term exposure to O3 (6 month hourly) and PM (12 months daily)

Analyzed citiesAnalyzed cities

London

Paris

Prague

Berlin

Copenhagen

Katowice

Milan

Marseille

Participating modelsParticipating models

CHIMERE INERIS-IPSL (France) O3, PM

EMEP MSC-W O3, PM

EPISODE NILU (Norway) O3

LOTOS TNO (Netherlands) O3, PM

MUSCAT IFT (Germany) O3, PM

MUSE AUT (Greece) O3, PM

REM FU Berlin (Germany) O3, PM

OFIS AUT (Greece) O3, PM

THOR NERI (Denmark) O3

CALGRID U. Brescia (Italy) O3

MOCAGE MeteoFrance (France) O3

STEM CESI (Italy) O3

EUROS RIVM (Netherlands) O3

TRANSCHIM CORIA (France) O3

Emission scenariosEmission scenarios

(0) 1999

(1) CLE (Current Legislation) 2010

(2) NOx MFR 2010

(Maximum Feasible Reduction)

(3) NOx (CLE+MFR)/2 2010

(4) VOC MFR 2010

(5) NOx and VOC MFR 2010

(6) PMcoarse MFR 2010

(7) PM2.5 MFR 2010

Berlin

Katowice

London

Milan

Paris

Prague

O3: 224 model runs for 6 months

PM: 89 model runs for 12 months

Available model runsAvailable model runs

CityDelta graphical interpretation toolCityDelta graphical interpretation tool

Monitoring dataMonitoring data

Validation with monitoring dataValidation with monitoring data

Deltas comparisonDeltas comparison

Spatial indicators & deltasSpatial indicators & deltas

Interpretation of the resultsInterpretation of the results

• Modeling teams submit results to JRC

• JRC processes data and loads them on the Internet

• Participants evaluate their results individually with the tool

• Discussion and joint interpretation at regular CityDelta meetings

• Synthesis of conclusions for integrated assessment modelling

Berlin Paris Milano London

1999-CLE

CLE-NOxMFR

CLE-VOCMFR

MEAN O3

DeltasDeltas for 1999-CLE, Berlin, mean Ofor 1999-CLE, Berlin, mean O33

8 2

12 16

DeltasDeltas for 1999-CLE, Berlin, mean Ofor 1999-CLE, Berlin, mean O33

0

20

40

60

80

100

120

1 2 3 7 8 9 10 11 12 16 29

1999 CLE

Population-weighted mean OPopulation-weighted mean O33 Berlin Berlin

Main Main iinitial nitial ffindings indings forfor long-term long-term OO33

• Emission inventories are crucial • Consistent difficulties in night time model predictions (too

high)• Day time predictions generally have smaller bias and

show less variability between models• Generally, predictions vs. measurements at finer scale

(down to 5 km) not significantly better than 50km scale– What does this have to say about policy tools? Do we

need develop tools down to street levels?

• However, NO2 predictions vs measurements are significantly better at finer scale – Does this indicate that finer scale is important for

modelling titration effects?

• Emission inventories are crucial and uncertain• Generally models underpredict concentrations, and

have difficulties reproducing the seasonal variation of the observations– What are models missing (coarse fraction, SOA,

representation of stable conditions, etc)?– Need a deeper review of secondary/primary

components• Validation against observations (PM2.5) with chemical

composition is absolutely necessary• Further scenarios are required before PM deltas can be

analysed (CityDelta Phase 2)

Main Main iinitial nitial ffindings indings forfor PMPM

http://rea.ei.jrc.it/netshare/thunis/citydelta