Search

Commuting flows and long-distance travel are important spreading factors of viruses and particularly airborne ones. Therefore, it is relevant to examine the association among diverse mobility scenarios and the spatial dissemination of SARS-CoV-2 cases. We intended to analyze the patterns of virus spreading linked to different mobility scenarios, in order to better comprehend the effect of the lockdown measures, and how such measures can be better informed. We simulated the effects of mobility restrictions in the spread of SARS-CoV-2 amongst the municipalities of two metropolitan areas, Lisbon (LMA) and Porto (PMA). Based on an adapted SEIR (Suscetible-Exposed-Infected-Removed) model, we estimated the number of new daily infections during one year, according to different mobility scenarios: restricted to essential activities, industrial activities, public transport use, and a scenario with unrestricted mobility including all transport modes. The trends of new daily infections were further explored using time-series clustering analysis, using dynamic time warping. Mobility restrictions resulted in lower numbers of new daily infections when compared to the unrestricted mobility scenario, in both metropolitan areas. Between March and September 2020, the official number of new infections followed overall a similar timeline to the one simulated considering only essential activities. At the municipal level, trends differ amongst the two metropolitan areas. The analysis of the effects of mobility in virus spread within different municipalities and regions could help tailoring future strategies and increase the public acceptance of eventual restrictions. [ABSTRACT FROM AUTHOR]

Green urban areas are a potential touristic attraction, providing opportunities for recreation and social interaction. In this study, two green areas in Lisbon were selected to investigate their influence on the thermal environment in and outside them and to analyse the usage of these parks in view of the perception of thermal comfort, the preferences and personal characteristics of the visitors. Measurements of temperature and relative humidity were carried out for several successive weeks in summer and in winter, in different locations around and inside the green areas. Temperature differences between the green spaces and the surrounding areas were greater in hotter conditions and reached up to 7°C difference at certain times on particular days. This cooling effect provided by green areas has a potential role in mitigating climate change impacts. In order to analyse the perception of thermal comfort and users' preferences, face-to-face interviews were carried out simultaneously with measurements of weather parameters. In summer, a positive correlation between the measured values of temperature and relative humidity with people's perception was observed. A significant association between individual's characteristics and type of usage of the parks was also revealed, particularly related to age and gender. Understanding the relationship between weather parameters, people's perception and visitors' preferences is paramount to create green areas more attractive and beneficial for the urban environment. [ABSTRACT FROM AUTHOR]

Abstract: Green areas in the urban environment can contribute to the mitigation of the Urban Heat Island. In a context of climate change, with the expected increase in temperature, dryness and intensity of heat waves, green areas assume even higher importance as they can create a cooling effect that extends to the surrounding areas. This study analyses the thermal performance of a small green space (0.24 ha) and its influence in the surrounding atmospheric environment of a densely urbanised area in Lisbon. Measurements of weather parameters (temperature, relative humidity, wind speed, solar and infrared radiation) were carried out along a selected path, starting from inside the green area to surrounding streets with different orientations and solar exposure. It was found that the garden was cooler than the surrounding areas, either in the sun or in the shade. These differences were higher in hotter days and particularly related to the mean radiant temperature (Tmrt). The highest difference found was of 6.9 °C in relation to air temperature and 39.2 °C in relation to Tmrt; in both cases this difference occurred between the shaded site inside the garden and the sunny site in an E–W oriented street in the southern part of the studied area. Besides the local weather conditions, particularly the low wind speed, the sun exposure and the urban geometry are the potential factors that explain these differences. The cooling effect of green areas on the surrounding environment can be enhanced by additional measures related to the urban features of each city. [Copyright &y& Elsevier]