## 3 Results and Discussion
### Pollution Concentrations Counter Measurements Efficacy Analysis
Data of daily precipitation are indicated in mm. Figure 10: Nitric oxide concentration variation related to the total block of urban traffic (green band) and alternated plates (red band) of December 2015. The blue line is the hourly pollutant concentration. The red dashed line is the daily mean pollutant concentration. Data of daily precipitation are indicated in mm. Figure 9: Carbon monoxide concentration variation related to the total block of urban traffic (green band) and alternated plates (red band) of December 2015. The blue line is the hourly pollutant concentration. The red dashed line is the daily mean pollutant concentration. Data of daily precipitation are indicated in mm. Figure 11: Nitrogen dioxide concentration variation related to the total block of urban traffic (green band) and alternated plates (red band) of December 2015. The blue line is the hourly pollutant concentration. The red dashed line is the daily mean pollutant concentration. Data of daily precipitation are indicated in mm. Figure 12: Nitrogen oxides concentration variation related to the total block of urban traffic (green band) and alternated plates (red band) of December 2015. The blue line is the hourly pollutant concentration. The red dashed line is the daily mean pollutant concentration. Data of daily precipitation are indicated in mm. Figure 13: Ozone concentration variation related to the total block of urban traffic (green band) and alternated plates (red band) of December 2015. The blue line is the hourly pollutant concentration. The red dashed line is the daily mean pollutant concentration. Data of daily precipitation are indicated in mm. In the days of the block of the urban traffic, both for the alternate plate or total block cases, the levels of pollutant concentrations are quite the same. As shown from the dashed red line representing the daily mean pollutant concentration, the level isn't affected by the policy strategy whenever it is an alternate plate or total block case. Focusing on the total block plate it is possible to notice a decrease of the particular matters [PM\({}_{10}\)] and [PM\({}_{2.5}\)] during November, January, and February in the following days. Nevertheless, this effect doesn't appear in December and it is possible to affirm that this kind of policy strategy can't have positive effects regarding the reduction of the pollutant emissions from urban traffic. About the alternate plates strategy, there aren't effects in the day and in the following days of application suggesting that also this kind of strategy didn't give any positive effect. Figures 5-15 reported the magnitude of rain in the period near the policy strategy thanked to reduce pollutant emissions. These values are useful in order to verify if the variation of the pollutant concentration can depend on the quantity of rain. Regarding the period taken into account seems that neither the rain can have a positive effect in order to reduce the pollutant concentrations. The analysis of actual counter measurements adopted in Italy leads to affirming that in Rome, and in more general in Italian cities, the policy strategy doesn't make a sensible  
Figure 5:0 Particulate matter PM\({}_{10}\) concentration variation related to the total block of urban traffic (green band) and alternated plates (red band) of December 2015. The blue line is the hourly pollutant concentration. Data of daily precipitation are indicated in mm. Figure 5:1 Particulate matter PM\({}_{2.5}\) concentration variation related to the total block of urban traffic (green band) and alternated plates (red band) of December 2015. The blue line is the hourly pollutant concentration. Data of daily precipitation are indicated in mm. variation of the pollutant concentrations. Every time there is the adoption of an alternate plate or total block of urban traffic there isn't a variation of the pollutant levels during the day of application of the measure and in the following days.