AUTHOR=Krüger Eduardo 

TITLE=Seasonal Effects of Daylight Conditions on Occupant Perception and Skin Temperature

JOURNAL=Frontiers in Sustainable Cities

VOLUME=Volume 4 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/sustainable-cities/articles/10.3389/frsc.2022.782712

DOI=10.3389/frsc.2022.782712

ISSN=2624-9634

ABSTRACT=Current research on the relationship between daylight and well-being has shown that access to daylight plays a relevant role both in terms of light perception and with respect to physiological mechanisms not directly related to vision. Such mechanisms include hormone secretion linked to the regulation of the sleep/wake cycle. In high-latitude locations with marked seasonal differences in available daylight (length of day and daily solar irradiance totals), lack of sunlight in winter can lead in extreme cases to seasonal affective disorder (SAD), the so-called winter depression. The aim of this paper is to analyze changes in reported light perception and in physiological responses, represented in this case by the skin temperature of research participants (n = 16) across three seasons (winter, shoulder and summer seasons). Sessions have been held in thermally stable rooms of a climate chamber, with daylight exposure to two opposing solar orientations of the glazed façade, namely equatorial and non-equatorial orientations, over 5-hour morning sessions. Differences in light perception as well as changes in physiology have been observed. Regarding light perception an increased sensitivity to changes in daylight were noticed in winter while such sensitivity dropped in seasons of the year with greater daylight availability. The same was verified for changes in skin temperature, which were found to be significantly related to daylight availability. Seasonal influence suggests that variability of brightness and correlated color temperature (CCT) of natural light can affect both psychological and physiological patterns in humans.