Browsing by Subject "UTCI"

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    Approaching environmental human thermophysiological thresholds for the case of Ankara, Turkey
    (Springer, 2020-10-27) Santos Nouri, Andre; Afacan, Yasemin; Çalışkan, O.; Tzu-Ping, L.; Matzarakis, A.
    The disclosed study undertook a ‘human centred-approach’ that ascertained and categorised environmental human thermophysiological risk factors by relating them to the human biometeorological system through the use of three widely utilised energy balance model (EBM) indices, the physiologically equivalent temperature (PET), the modified PET, and the universal thermal climate index (UTCI). The disclosed assessment was carried out over the past decade (i.e., 2010–2019) with a 3-h temporal resolution for the case of Ankara through two WMO meteorological stations to compare both local urban and peri-urban environmental conditions. The study recognised extreme annual variability of human physiological stress (PS) during the different seasons as a result of the biometeorological processing of the singular variables, which in the case of average PET for both stations, varied by up to 75 °C between the winter and summer for the same annual dataset (2012). In addition, all EBMs indicated higher heat stress within the city centre that were conducive of both urban extreme heatwaves and very hot days during the summer months, with extreme heat stress levels lasting for longer than a week with PET values reaching a maximum of 48 °C. Similar cold extremes were found for the winter months, with PET values reaching − 30 °C, and average PS levels varying lower in the case of the peri-urban station.
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    ItemOpen Access
    Human thermo-physiological comfort assessment in Lisbon by local climate zones on very hot summer days
    (Frontiers Research Foundation, 2023-05-17) Reis, C.; Nouri, Andre Santos; Lopes, A.
    Extreme heat is a current and future issue on urban areas, with negative impacts on health and quality of life (increasing morbidity and mortality rates). This paper analyses day (12:00–15:00 h) and nighttime (00:00–03:00 h) thermo-physiological comfort (TC) conditions by Local Climate Zones (LCZ) in Lisbon during a particular Local Weather Type (LWT), very hot summer days. For this, 13 different microscale sample areas were chosen covering urban and non-urban land cover classes (LCZs 1–3, 4–6, 8, 9, A and B). Universal Thermal Climate Index (UTCI) and Mean Radiant Temperature (MRT) were modeled on SkyHelios software for 163 days between 2008 and 2014. Results show that during the day all urban LCZ samples depict the same average TC conditions (average UTCI of 34°C—strong heat stress) and densely wooded areas are 2°C cooler (average UTCI of 32°C—moderate heat stress). However, compact areas (LCZs 1–3) with low sky view factor and some vegetation (street trees) display lower percentages of area with higher thermo-physiological discomfort (TD) levels (83% with strong heat stress against 98% in LCZs 8 and 9 and 100% in LCZs 4–6). When considering the hottest days (air temperatures equal or above 35°C—75th percentile), the moderate heat stress class disappears in all samples and the very strong heat stress class appears only on urban areas, occupying between 12% and 16% on LCZs 1–3, 10%–22% on LCZs 4–6, 16%–22% on LCZs 8 and 9 on LCZ 9. During the nighttime period all samples show no thermal stress, favoring nocturnal physiological recovery. TC conditions in Lisbon are strongly influenced by solar radiation and wind, which explains the need to increase the shading area, preferably by trees, and to promote and preserve ventilation paths.