1. Serena Falasca (1,2) and Gabriele Curci (1,2)
Air quality high resolution simulations of Italian urban areas with WRF-CHIMERE
Serena Falasca (1,2) and Gabriele Curci (1,2)
Department of Physical and Chemical Sciences, University of L’Aquila, L’Aquila, Italy.
Centre of Excellence CETEMPS, Department of Physical and Chemical Sciences, University of L’Aquila, L’Aquila, Italy.
European Geosciences Union General Assembly 2017 Vienna | Austria | 23–28 April 2017

2. Motivation and Aim of the study
KEY POINTS
The entity of urban population and the expectation of its growth in the next decades
WHO defines "Air pollution" as a major environmental risk to human health
The European Directive 2008/50/EC on ambient air quality and cleaner air for Europe encourages the use of modeling techniques to support the observations in the assessment and forecasting of air quality.
BACKGROUND AND MOTIVATION
The ultimate aim of this work: development and assessment of an air quality modeling tool (WRF + CHIMERE) at high resolution

3. THE DOMAINS Land Use Categories d01 d02 METHOD d03 d04
Horizontal Resolution
dx = dy WRF (km)
dx = dy CHIMERE (°)
d01 (EUR) 36
0.5
d02 (ITA) 12
0.12
d03 (North-West of Italy) 4
0.04
d04 (Urban Area of Milan)
1.3
0.015

4. Simulations The increase of the horizontal resolution
 Label 
dx = dy (°)
EUR
0.5
ITA
0.12
NWI
0.04 MI
0.015
The reallocation of anthropogenic emissions
 Label
Reallocation of emissions
CTNNF N
CTNGC Y
d04
The use of Urban Schemes for WRF simulations
  Label
Urban Scheme (WRF namelist option)
CTNGC
None
SLUCM
Single Layer Urban Canopy Model (1)
BEP
Building Environment Parameterization (2)
Increasing the complexity
d04

5. The increase of the horizontal resolution: comparisons
Jan 2010
Jul 2010
CHIMERE
RESULTS
24 h mean PM10 (µg/m3)
Station ID: IT1812A
Zone: Rural
Type: Background
Maximum daily 8 h mean O3 (µg/m3)
Station ID: IT1466A
Zone: Suburban
Type: Background
OBS
EUR
ITA
NWI MI

6. The reallocation of emissions: comparisons
Emission flux of PM10 at 12:00 UTC for January 2010
Emissions inventory: CTN (5 x 5 km)
CTNNF
Emissions inventory: CTN (5 x 5 km) +
CTNGC
GlobCover Land Use dataset

7. 24 hour mean PM10 (µg/m3): Difference CTNGC-CTNNF
The reallocation of emissions: comparisons
24 hour mean PM10 (µg/m3): Difference CTNGC-CTNNF
Mean
Maximum 25 6
CHIMERE RESULTS
Jan 2010 6 25
Jul 2010 25

8. Maximum daily 8 h mean O3 (ppb): Difference CTNGC-CTNNF
The reallocation of emissions: comparisons
Maximum daily 8 h mean O3 (ppb): Difference CTNGC-CTNNF
Mean
Maximum
CHIMERE RESULTS
2.5 20
Jan 2010 -5 20
2.5
Jul 2010 -5

9. The use of Urban Schemes: comparisons
Jan 2010
Jul 2010
24 hour mean PM10 (µg/m3)
CHIMERE
RESULTS
Station ID: IT0776A
Zone: Urban
Type: Traffic
Maximum daily 8 hour mean O3 (µg/m3)
Station ID: IT0706A
Zone: Urban
Type: Background
OBS
CTNGC
SLUCM
BEP

10. The use of Urban Schemes: comparisons
24 h mean PM10 (µg/m3): Maximum difference
SLUCM-CTNGC
BEP-CTNGC
CHIMERE RESULTS 20 20
Jan 2010 10 10
Jul 2010

11. The use of Urban Schemes: comparisons
24 h mean PM10 (µg/m3): Mean difference
SLUCM-CTNGC
BEP-CTNGC
2.5
2.5
CHIMERE RESULTS
Jan 2010
-10
-10
0.5
0.5
Jul 2010
-1.5
-1.5

12. The use of Urban Schemes: comparisons
Maximum daily 8 h mean O3 (ppb): Maximum difference
BEP-CTNGC
SLUCM-CTNGC
CHIMERE RESULTS 25 25
Jan 2010
12.5
12.5
Jul 2010

13. The use of Urban Schemes: comparisons
Maximum daily 8 h mean O3 (ppb): Mean difference
SLUCM-CTNGC
BEP-CTNGC
7.5
7.5
CHIMERE RESULTS
Jan 2010
0.5
0.5
Jul 2010 -7 -7

14. CONCLUSIONS
High resolution simulations of an urban area in Italy have been performed using the reallocation of anthropogenic emissions and different urban schemes
The use of the reallocation of anthropogenic emissions for high resolution simulations allows a more realistic reproduction of the emission fluxes and therefore of the concentrations of the pollutants.
Benefits of the reallocation of anthropogenic emissions are relevant for simulations of urban areas.
Future work: use characteristic morphologic parameters for the simulated urban areas

15. ACKNOWLEDGEMENTS
This work is carried out in the frame of the "Smart Clean Air City L'Aquila" project, Italian Ministry of the Economic Development, codice programma n. M/0007/03/X23.
The computational resources were provided by CINECA in the frame of IscraC projects NMTFEPRA e PANCIA.

16. WRF physics options SUPPLEMENTARY MATERIAL
Physics Category (namelist.input option)
Scheme (namelist.input option)
Shortwave radiation (ra_sw_physics)
RRTMG (4)
Longwave radiation (ra_lw_physics)
microphysics (mp_physics)
WSM6 (6)
Surface layer (sf_sfclay_physics)
Revised MM5 Monin-Obukhov (1)
Planetary Boundary Layer (bl_pbl_physics)
Bougeault and Lacarrere (BouLac) (8)
Land Surface (sf_surface_physics)
Unified Noah land-surface model (2)
SUPPLEMENTARY MATERIAL