• Model used in « Source Apportionment of Airborne Particulate Matter in the UK » [Stedman et al., Receptor modelling of PM10 concentrations at a UK national network monitoring site in central London, Atmospheric environment (35) 297-304 (2000)]

• PM10 = A * [NOx urban] (surrogate of PM from local combustion)

+B * [SO4 rural] (surrogate of secondary regional PM )

+C (other PM : crustal material, marine aerosol,…)

Statistical model of PM10 origin in the urban atmosphere

UNECE-CLRTAP and EMEP Task Force on Integrated Assessment Modelling27th session, Oslo, 13-15 May 2002

Location of cities (blue) and rural SO4 monitoring stations (red)

UNECE-CLRTAP and EMEP Task Force on Integrated Assessment Modelling27th session, Oslo, 13-15 May 2002

Clermont-Ferrand : comparison between model and observations

0

10

20

30

40

50

oct-95févr-9

6

mai-96

août-96

déc-96

mars-97

juin-97

sept-97

janv-98avr-9

8juil-9

8nov-98

févr-99

µg

/ m

3

MeasuredPM13Concentration

ModelledPM13concentrations

UNECE-CLRTAP and EMEP Task Force on Integrated Assessment Modelling27th session, Oslo, 13-15 May 2002

Clermont-Ferrand : variability of local and regional contributions to

ambient PM

0

10

20

30

40

50

oct-95

févr-96

mai-96

août-96

déc-96

mars-97

juin-97

sept-97

janv-98avr-9

8juil-9

8

nov-98

févr-99

µg

/ m

3

Measured PM13Concentration

Contribution oflocalcombustion

Contribution ofregional PM

UNECE-CLRTAP and EMEP Task Force on Integrated Assessment Modelling27th session, Oslo, 13-15 May 2002

Paris : seasonnality of local and regional contributions to ambient

PM

0

5

10

15

20

25

30

35

40

45

50

janv

-98

févr

-98

mar

s-98

avr-

98m

ai-9

8ju

in-9

8ju

il-98

août

-98

sept

-98

oct-

98no

v-98

déc-

98ja

nv-9

9fé

vr-9

9m

ars-

99av

r-99

mai

-99

juin

-99

juil-

99ao

ût-9

9se

pt-9

9oc

t-99

nov-

99dé

c-99

janv

-00

févr

-00

mar

s-00

avr-

00m

ai-0

0ju

in-0

0ju

il-00

août

-00

sept

-00

oct-

00no

v-00

déc-

00

µg/m3

Measured PM10concentration

Estimatedcontribution fromlocal combustions

Estimatedcontribution fromregional PM

UNECE-CLRTAP and EMEP Task Force on Integrated Assessment Modelling27th session, Oslo, 13-15 May 2002

Overview of local/regionalcontributions for four

cities

40%

40%

20%

50%

20%

30%

35%

40%

25%

35402550%

25%

25%

Clermont-Ferrand Caen

Paris 12ème Vitry-sur-Seine (Paris suburban)

UNECE-CLRTAP and EMEP Task Force on Integrated Assessment Modelling27th session, Oslo, 13-15 May 2002

Refined model for PM apportionment in a Suburban Paris site

• Both PM10 and PM2.5 being available at Vitry (suburban Paris), a more refined apportionment model has been applied, identifying specifically the contribution of coarse particles (construction, road abrasion, brake and tyre wear, construction, mineral dust,...). This contribution amounts to 36% of ambiant PM10.

• Mean unexplained PM10 concentration is below 1 µg/m3• The « local combustion » and « regional PM » , as identified

by the model, are almost enterely in the PM2.5 size range.• For this suburban Paris site, the share of « local combustion »

in PM2.5 ambiant concentration is higher than that for PM10 (70% for PM2.5 versus 50% for PM10).

Refined model for PM apportionment in a Suburban Paris site : results for

PM10.

0

5

10

15

20

25

30

35

sep

t-9

9

oct

-99

no

v-9

9

dé

c-9

9

jan

v-0

0

févr

-00

ma

rs-0

0

avr

-00

ma

i-0

0

juin

-00

juil-

00

ao

ût-

00

sep

t-0

0

oct

-00

no

v-0

0

dé

c-0

0

µg/m3

Measured concentrations

Estimated contribution fromlocal combustion

Estimated contribution fromregional PM2,5

Estimated share of coarseparticules (both local orlong-range)

Refined model for PM apportionment in a Suburban Paris site : results for PM2.5

0

5

10

15

20

25se

pt-

99

oct

-99

no

v-9

9d

éc-

99

jan

v-0

0

févr

-00

ma

rs-0

0

avr

-00

ma

i-0

0

juin

-00

juil-

00

ao

ût-

00

sep

t-0

0o

ct-0

0

no

v-0

0

dé

c-0

0

µg/m3

Measuredconcentrations

Estimatedcontribution fromlocal combustion

Estimatedcontribution fromregional PM

Some concluding remarks

• Both local sources and regional concentrations are important to explain ambiant PM10 concentration in the cities studied here.

• Local combustion involved through: - Transport : primary PM, secondary PM from NOx

and VOC emissions. - Heating : the case of Paris in winter ??

• The share of local combustion increases when considering PM2.5 instead of PM10 for the case in suburban Paris studied.

UNECE-CLRTAP and EMEP Task Force on Integrated Assessment Modelling27th session, Oslo, 13-15 May 2002