Vamos passear na floresta! O conforto térmico em fragmentos florestais urbanos

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Esta pesquisa investigou o papel dos fragmentos florestais urbanos no conforto térmico. Para tanto, foram monitoradas cinco localidades na cidade de Campinas (Brasil) durante o verão, outono e inverno de 2009. Os dados microclimáticos foram obtidos com o uso de uma estação meteorológica portátil, que mediu temperatura e umidade do ar, radiação, velocidade do vento e temperatura de globo. Além disso, aplicou-se questionários estruturados e fez-se observações de campo para a avaliação das condições de conforto térmico e da percepção ambiental dos usuários. Os índices PMV e PET foram calculados com o software RayMan 1.2 e comparados com os votos dados nas entrevistas. Os resultados indicam que os fragmentos florestais urbanos contribuem para o conforto térmico. A porcentagem de indivíduos sob condição de neutralidade térmica varia entre os índices: 72,4% consideravam-se confortáveis; 63,3% encontravam-se na faixa de temperatura PET entre 18 Â°C e 23 º C; e 39,8% estavam na faixa de conforto do PMV entre -0,5 a +0,5. Os usuários percebem os bosques como locais confortáveis, o que é atribuído à presença da natureza. No entanto, notam problemas relacionados à conservação e à ocupação das áreas. O microclima específico da floresta, o ar fresco e a percepção de ar puro foram citados pela população e podem ser relacionados ao conforto ambiental.

Translated abstract

This study investigated the role of urban forest fragments in thermal comfort. For that purpose, five different locations in the city of Campinas (Brazil) were monitored during the summer, autumn and winter of 2009. Microclimatic data were obtained with the use of a portable weather station that measured air temperature, air humidity, radiation, wind speed and globe temperature. In addition, structured interviews and field observations were carried out to evaluate the thermal comfort conditions and the occupants' perceptions of their environment. The PMV and PET indices were calculated by the RayMan 1.2 software and compared with the actual votes obtained through the interviews. The results indicate that urban forest fragments improve thermal comfort. The percentage of subjects reported as thermally neutral varied between indices: 72.4% were found comfortable, 63.3% were in the PET limit of 18-23º C, and 39,8% were in the PMV range of -0.5 to +0.5. Occupants perceived those places as comfortable, linking this to nature, but they also observed some problems regarding conservation and occupation. The specific forest microclimate, fresh air, and the perception of clean air were also cited by the population and can be linked to environmental comfort.

Related collections

Most cited references 27

Record: found
Abstract: found
Article: not found

The physiological equivalent temperature - a universal index for the biometeorological assessment of the thermal environment.

P Hoppe (1999)

With considerably increased coverage of weather information in the news media in recent years in many countries, there is also more demand for data that are applicable and useful for everyday life. Both the perception of the thermal component of weather as well as the appropriate clothing for thermal comfort result from the integral effects of all meteorological parameters relevant for heat exchange between the body and its environment. Regulatory physiological processes can affect the relative importance of meteorological parameters, e.g. wind velocity becomes more important when the body is sweating. In order to take into account all these factors, it is necessary to use a heat-balance model of the human body. The physiological equivalent temperature (PET) is based on the Munich Energy-balance Model for Individuals (MEMI), which models the thermal conditions of the human body in a physiologically relevant way. PET is defined as the air temperature at which, in a typical indoor setting (without wind and solar radiation), the heat budget of the human body is balanced with the same core and skin temperature as under the complex outdoor conditions to be assessed. This way PET enables a layperson to compare the integral effects of complex thermal conditions outside with his or her own experience indoors. On hot summer days, for example, with direct solar irradiation the PET value may be more than 20 K higher than the air temperature, on a windy day in winter up to 15 K lower.