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Brescia meeting review & Definition of the new base case. 3 km. 6 km. 50 km. To be checked by modelling groups CHIMERE : scale consistency of the results between 3 and 6 km (time step?) EMEP : Problems related with meteorology (high peaks in mountain areas)
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3 km 6 km 50 km
To be checked by modelling groups CHIMERE: scale consistency of the results between 3 and 6 km (time step?) EMEP: Problems related with meteorology (high peaks in mountain areas) CAMx: Good correlations buthigh summer O3 values. RCG: Temporal distribution for PM components AURORA: Only two months available. High O3 summer values TCAM: Good performance for O3 but strange seasonal distribution for PM Results Overview: Brescia (February 2009) Overall: - Large underestimation of the PM levels. - Large variability among models for O3 levels
Check individual models Model presentations: Improvements to the models & interpretation of the results Check emissions (Cinzia) Check meteorology (Emilia) Sensitivity tests Definition of a new base- case
Sensitivity runs: CHIMERE, January, 6km • Meteorology • Wind speed divided by 2 at surface, unchanged at model top, linear decrease in between • Increase of roughness length uniform to 0.5 m everywhere • Use of nudging option in MM5 • Emissions • Seasonal re-allocation of wood burning emissions (PM & VOC *1.3, NOx unchanged) • Uncertainty on emission factors from wood burning (PM * 2.3, VOC * 1.3) • Uncertainty on emission factors from transport (PM & VOC * 1.25, NOx * 1.1) • Impact of temporal distribution of the heating emissions (in terms of degree-days) • Informatic • From 32 to 64 bits machine • General • Impact of local (i.e. Po-Valley) surface and point sources • Impact of transport and residential heating sector sources • Impact of NH3 emissions
Check emissions Check meteorology Sensitivity tests Definition of a new base-case • Nudged MM5 meteorology • New temporal factors for wood burning
Delivery status Notes - MM5 meteorological data (Kz = 0 from 18/06 to 12/08) - All model results uploaded in the tool
Base case 2 Base case 1 vs. Base case 2 Impact of spatial resolution: 6 km vs. 3 km First results for 2012 CLE scenario Conclusions & discussion
O3 BC1
O3 BC1
BC2: Change in emissions PM2.5 – PM10 VOC Mountain Mountain Plain
OBS +8% +10% - +13% - -20%
Emis. Incr. -15% +5% +30% +45% +20% 0%
2% 47% 8% 15% 45% 10%
Lombardy Ispra BC1 BC2 PM10 Milan Bormio
Lombardy Ispra BC1 BC2 O3 Milan Bormio
O3 July CAMx
PM10 January CAMx
33.8 40.3 January 72.6 76.7 ISPRA
20.1 21.5 45.0 45.9
Bound. conditions PM 10%
Bound. conditions O3 5%
There is an overall improvement with the BC2 results, especially for PM. Levels are in average 10% larger in winter and correlations and predictions of exceed. days are improved. O3 is mostly unchanged and in good agreement with observations (averages and time variations). PM is still largely underestimated (35% yearly for the model ensemble) Importance of meteorology (sensitivity tests & BC2) Speciation (Ispra). Good for SIA (TCAM?) but lack of Particulate organic matter No impact from 6 to 3 km Little impact of 2012 CLE emission reductions (5 to 10% decrease for PM and 5 to 10% increase for O3 averages)
Models do react differently to the BC2 changes (e.g. EMEP, RCG…). Temporal variations are shifted: many models predict higher concentrations in Oct-Nov and show little changes between BC1 and BC2. Some models do show opposite behaviour (EMEP) Impact of scale resolution (from 50 to 6) for PM is very different for EMEP and CHIMERE (55% vs 3% for BC2 yearly, 75% vs. -3% winter). For summer O3, it is more consistent: 30% vs 50%. No major changes for O3 overall averages but significant changes in terms of correlation and standard deviation for RCG and TCAM. Some significant changes in PM speciation for some models (e,g. POM for TCAM) Further work: - Understand better model differences - 6km vs 3 km - Meteorology - Vertical profiles