## 2 Materials and Methods
### ENVI-Met Model Setup and Calibration  
The simulation domain was configured within ENVI-met V5.6 to replicate the microclimatic and pollutant dispersion conditions of the university campus of Catania. The selected area spans approximately 360 m \(\times\) 360 m with a vertical domain extending up to \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Sensor** & **Measurement Range** & **Accuracy** & **Resolution** \\ \hline Air temperature & \(-\)40–65 \({}^{\circ}\)C & \(\pm\)0.3 \({}^{\circ}\)C & 0.1 \({}^{\circ}\)C \\ Relative humidity & 1–100\% & \(\pm\)2\% & 1\% \\ Wind speed & 0–89 m/s & \(\pm\)0.9 m/s & 0.1 m/s \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Technical features of the Davis Vantage Pro 2 stationary weather station. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Sensor** & **Measurement Sensor** & **Measure Range** & **Accuracy** & **Resolution** \\ \hline LPC &
\begin{tabular}{c} Particulate matter \\ (PM\({}_{2.5}\), PM\({}_{10}\)) \\ \end{tabular} & 0.001–1000 & \(\pm\)(5 mg/m\({}^{3}\) + 15\% & \multirow{2}{*}{0.001 mg/m\({}^{3}\)} \\ - & Air temperature & \(-\)5–45 \({}^{\circ}\)C & & \\ - & Relative humidity & 0–95\% & & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Technical features of the Aeroqual S500 portable sensor. 50 m. The computational grid consists of 180 \(\times\) 180 \(\times\) 25 cells, each 2 m in width, length, and height, with telescopic stretching above 20 m in the vertical direction to optimize simulation efficiency. To reduce boundary effects, six nested grid cells were applied at each edge. To accurately reproduce the topography, Digital Elevation Models (DEMs) were incorporated into the model setup. This allowed the terrain's natural slope and local altitude variations to influence airflow and surface temperature distribution, improving the physical reliability of the microclimate simulations. Figure 4 displays the modeled domain under the baseline scenario, both with (Figure 4a) and without (Figure 4b) the DEM. Urban materials used in the simulation were classified into six surface types, each assigned with specific values of albedo (\(\rho\)) and thermal emittance (\(\varepsilon\)), as shown in Table 5. These values reflect the typical properties of surfaces found on campus, such as asphalt, concrete, and plastered building walls. The albedo and emissivity values were extracted from the general ENVI-met database and are consistent with those reported in several studies and scientific papers [64; 65; 66; 67; 68]. Vegetation was also carefully parameterized. Tree canopies, hedges, and grass layers were modeled with detailed inputs on albedo, emissivity, and Leaf Area Density (LAD). Table 6 reports the thermophysical properties assigned to the various plant types simulated in the model, which include coniferous and deciduous trees, shrubs, and grass with realistic heights and densities based on on-site surveys [64; 65; 66; 67; 68]. Figure 4: Baseline scenario modeled in ENVI-met: (**a**) with the inclusion of the Digital Elevation Model (DEM); (**b**) without the inclusion of the DEM. \begin{table}
\begin{tabular}{l l l l l l} \hline \hline \multirow{2}{*}{**No.**} & \multicolumn{2}{l}{**Urban**} & \multirow{2}{*}{**Color**} & \multirow{2}{*}{**Name**} & \multirow{2}{*}{**Albedo (\(\rho\))**} & \multicolumn{1}{l}{**Theral**} \\  & \multicolumn{1}{l}{**Component**} & & & & \\ \hline
1 & Ground, soil & Dark green & Sandy loam & 0.20 & 0.90 \\  & & & Concrete & & \\
2 & Pedestrian & & & pavement & 0.30 & 0.90 \\  & roads & & grey & & \\
3 & Clay brick & & & Brick & & \\  & building roofs & & & pavement & \\
4 & Concrete & & & Brick & & \\  & building roofs & & & pavement & & \\
5 & Roads & Black & Asphalt roads & 0.12 & 0.90 \\
6 & Parking & Black & Asphalt roads & 0.12 & 0.90 \\
7 & Building walls & Light grey & Plaster & 0.60 & 0.90 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Thermal and optical properties of input materials in ENVI-met.