Fig. 1. View of area for ENVI-MET V.4 simulation, the archaeological area in red. The research methodology consists of comparing the results of the simulation of the outdoor microclimate, created with the ENVI-MET V.4 software, the current configuration is modelled with a simplification (considering only trees of one specie) and validated with real data from two meteorological stations, then two other options scenarios are si- mulated: without trees, and with more heterogeneous trees. The results For the modelling it is necessary to define a boundary of the study area; for the case study the boundary of the area for modelling has been chosen with an extension so as to include the first buildings around the Area of Ecological Rebalancing of the Roman Villa of Russi (Fig. 1). The data criteria and approximations are described below. The selected area has an extension so as to include the first buildings around the Area of Ecological Rebalancing. The dimensions of the cells which compose the grill are 4m, dimensions chosen, so that one room of the villa Pearson Correlation between Weather Station and Meteoblue, and Weather Station or Meteoblue and ENVI-MET results, only for air temperature (°C). Table 3 tig. 2. View of Villa Romana of Russi, (left) basement structure of the plan/floor, (right) view of covered area of Villa Romana of Russi, we can observe mosaics and cover (photo ¢ canuti). Operative Temperature following ISO 7726. Table 1 Table 2 Pearson Correlation between Weather Station and Meteoblue, and ENVI-MET results, for all climate data variables (air temperature, relative humidity and wind speed). Fig. 4. Graphics with Weather Station or Meteoblue and ENVI-MET simulation correlation Temperature. Mean Radiant Temperature (°C) values variation during summer and winter day, in order to evaluate thermal shock of the archaeological area materials, between comparison data by hour 15:00 (Tmax) and hour 7:00 (Tmin). 4.3. The choice of days for the simulation greatest flow of summer visitors, while 22 December was chosen as the winter day, among the coldest, with the greatest number of visitors. Fig. 5. Trend of Air temperature (°C) of Weather Station, Meteoblue and ENVI-MET Simulation 25 July (left) and 22 December 2015 (right). Dots report trend values in case of: HO = Homogeneous Trees, HE = Heterogeneous Trees, WO = Without Trees. Air-Temperature (°C) values in summer by 25 July at 15:00, the Ta min and Tamax Values refer to a single area of the OMM Archaeological covered sites and Archaeological Outdoor sites not covered. Relative Humidity (%) values variation during summer and winter day, evaluate a pos- sible hygrothermal shock of the archaeological area materials, between comparison data by hours 15:00 (RH min) and hours 7:00 (RH max). Reflected sw Radiation in SUMMER measured in W/m?, values are refer to single area of the OMM Archaeological covered sites and Archaeological Outdoor sites not covered (Fig. 13). Fig. 6. OMM Mean Radiant Temperature in summer. The Operative Temperature is defined in ISO 7730 as “uniform temperature of an imaginary black enclosure in which an occupant would exchange the same amount of heat by radiation and convection as in the actual non-uniform environment” is not provided by ENVI-MET V.4, and was calculated according to ISO 7726 Annex G (ISO, 2017b) with the formula (1): In Table 1 the values of the operating temperature t, are reported, which fall within the conditions of well-being in the case of light ac- tivity, 50% relative humidity and air velocity < average of 0.15 m/s. The values refer to the indoor comfort conditions, in the absence of si- milar values for outdoor conditions we can consider these guidance values Fig. 7. OMM Mean Radiant Temperature in winter. the tourists, we consider that the choice of another parameter of sen- sation is however valid. 4.7. Reflected radiation With regards to the reflection of the radiation, this is a parameter which is interesting both for the purposes of the visitors’ comfort and that regarding the conservation of the surfaces. Depending on the species, the tree reflection changes considerably. The amount of intercepted radiation depends on the density of the fo- liage and varies depending on the species. In fact, type, size and ar- rangement of the leaves play an important role in improving the ab- sorption of radiation and reflection. Generally this is in relation to the LAI parameter (leaf area index, dimensionless value) which is defined as the total leaf surface that intercepts the light energy expressed in relation to the area of the ground below. Fig. 9. OMM Relative Humidity in winter. Fig. 10. OMM Wind Speed in winter and summer at 15:00. Fig. 11. OMM and legend about Air-Temperature (°C) in summer 25 July at hours 15:00. Having clarified that the numerical model is validated, the next paragraph reports the reading of the results, in order to understand the role of vegetation in the archaeological areas. As specified in the Research objectives paragraph, we are interested in checking if a modelling with the limits described in the previous paragraphs and validated, allows us to obtain results that are applicable also to other disciplines such as, for example, archaeology and restoration, also in order to guide the planning choices made regarding the use of vege- tation in archaeological areas. Fig. 13. OMM and legend relative about Reflected sw Radiation in summer 25 July at hours 15:00. Appendix A Fig. A2. Graphics of the Mean Radiant Temperature distribution in SUMMER: on x-axis MRT values and in y-axis the percentage distribution. Fig. A4. Graphics of Relative Humidity frequency distribution in WINTER, with highlight range values following UNI 10829 (in case of stone mosaic, stone, etc.) and DM 10/2001 (in case of mosaic). How we can see all values are out of UNI and DM range, that’s’ because Villa are in outdoor site. Fig. A5. Graphics of Wind Speed (m/s) in summer, on x-axis w, values and in y-axis the percentage distribution. Fig. A6. Graphics Frequency of Air-Temperature (°C) in summer 25 July at hours 15:00. UNI 10890 range is between 15 °C and 25 °C and DM 10/2011 range is between 6°- 25 °C, we highlight that simulated values are in outdoor and not-covered area. Fig. A7. Graphics Frequency of Reflected sw Radiation in i summer 25 July at hours 15:00. Weather data from the weather station in Russi and from Meteorological reanalysis (by Meteoblue) on 25 July 2015 and 22 December 2015. Table Al Weather data results by ENVI-MET simulation in 25 July 2015 and 22 December 2015. Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.scs.2017.07.020. Appendix B. Supplementary data
