1. TFMM PM Assessment Report
workshop
Q1: Are there significant differences in the PM climate across Europe?
Q4: How important are natural PM sources
Q5: To what extent do sources outside Europe contribute to European PM ?
Faced difficulties answering these questions before having National Contributions in hands

2. Q1: Are there significant differences in the PM climate across Europe ?
- PM mass concentrations: YES
from PM national monitoring data when stratified according to site types (if not ≠ % of rural, urban background, kerbside sites may confuse the picture)
also from remote sensing (AOD and lidar), which can be give information on PM mass at ground level
factors controlling PM mass concentrations are:
- pollutant dispersion (orography + meteorology)
- emissions
- transboundary transport

3. - PM2.5 / PM10 ratios at both rural and urban sites: YES
yearly av. PM2.5 / PM10 ratios are significantly lower at sites where specific sources of coarse particles are significant
yearly averages may hide large day-to-day and seasonal variability
seasonal variability in PM2.5 / PM10 also related to variations in mineral dust concentrations
PM2.5 / PM10 depends even more on siting and specific events (e.g. precipitation, sporadic transport)

4. - Issues related to PM mass concentrations
how much can the observed differences be artifact – driven
gravimetric vs. TEOM
TEOM correction factor (FDMS advisable)
water

5. - PM2.5 and PM10 av. chemical composition at rural sites: YES
NO3 / SO4 decreases from W to E
NO3 / SO4 decreases from N to S
! NO3 and SO4 may sit in different size fractions !
OM / 2-ndary inorganics ranges from 0.5 to 1.2 (Carbosol)
OM / EC ranges from 5 to 11 (Carbosol), even 15 (ES)
EC / PM is 1 to 5%
OM / PM is 9 to 37 %
mineral dust
differences in PM2.5 vs differences PM10 composition
PM2.5 and PM10 chemistry at rural sites during episodes: YES
>> dust, NH4NO3, POM from wood burning
domestic and forest fires

6. - PM2.5 and PM10 av. chemical composition at urban sites: YES
because urban PM is affected by regional PM
mineral dust in both PM10 and PM2.5
EC contribution ? No data to answer
- PM2.5 and PM10 chemistry at rural sites during episodes: YES
dust (re)suspension from winter and studded tires
Saharan dust
sea salt

7. Issues related to PM chemical speciation
sampling
OC /EC (charring and charring correction)
OC to OM conversion factor
dust calculation

8. Q4: How important are natural PM sources ?
More for PM10 than for PM2.5
Mineral dust:
up to 500 ug / m3 in the Mediterranean basin, leading to exceedances a year
up to 15 ug / m3 annual average in the Med. Basin
about 1 ug / m3 in Northern Europe
Sea spray
up to 35 ug / m3 at coastal sites, can lead to exceedances
up to ug/m3 annual average in Canary Islands
7 ug/m3 at coastal sites
< 1 ug/m3 at continental sites
- bioPOM (primary and secondary) based on literature
PSI and Carbosol studies
- H2O (NaCl or secondary inorganics- linked ?)

9. Issues related to natural PM sources ?
Mineral dust:
quantify and distinguish between road dust and desert dust
resuspended and wind blown
- BioPOM
- C14 + wood combustion tracer measurements needed
H2O
direct measurements are difficult
Also consider the report ordered by EC DG ENV on this topic

10. Q5: To what extent do sources outside Europe contribute to European PM ?
Few data available to answer this question. CLRTAP TF on hemispheric transport modeling is addressing this question.
On average:
About 1 ug/m3 from N. America reaching the NL
< 1 ug/m3 reaching Izana and Mace Head (see literature)
Ship emissions from outside the EMEP domain to be looked at
Episodes:
- Large scale fires in North America (see papers in literature)
Large scale forest fires in Siberia affecting Scandinavia (Risto)
Transport from India to the East of the domain (e.g. Cyprus)