Citation

Nakayoshi M, Kanda M, Shi R, de Dear R. Int. J. Biometeorol. 2014; 59(5): 503-515.

Affiliation

Department of Civil Engineering, Tokyo University of Science, 2641, Yamasaki, Noda city, Chiba Prefecture, 278-8510, Japan, nakayoshi@rs.tus.ac.jp.

Copyright

(Copyright © 2014, International Society of Biometeorology, Publisher Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/s00484-014-0864-y

PMID

25011423

Abstract

An outdoor summer study on thermal physiology along subjects' pathways was conducted in a Japanese city using a unique wearable measurement system that measures all the relevant thermal variables: ambient temperature, humidity, wind speed (U) and short/long-wave radiation (S and L), along with some physio-psychological parameters: skin temperature (T skin), pulse rate, subjective thermal sensation and state of body motion. U, S and L were measured using a globe anemo-radiometer adapted use with pedestrian subjects. The subjects were 26 healthy Japanese adults (14 males, 12 females) ranging from 23 to 74 years in age. Each subject wore a set of instruments that recorded individual microclimate and physiological responses along a designated pedestrian route that traversed various urban textures. The subjects experienced varying thermal environments that could not be represented by fixed-point routine observational data. S fluctuated significantly reflecting the mixture of sunlit/shade distributions within complex urban morphology. U was generally low within urban canyons due to drag by urban obstacles such as buildings but the subjects' movements enhanced convective heat exchanges with the atmosphere, leading to a drop in T skin. The amount of sweating increased as standard effective temperature (SET*) increased. A clear dependence of sweating on gender and body size was found; males sweated more than females; overweight subjects sweated more than standard/underweight subjects. T skin had a linear relationship with SET* and a similarly clear dependence on gender and body size differences. T skin of the higher-sweating groups was lower than that of the lower-sweating groups, reflecting differences in evaporative cooling by perspiration.

Language: en