Thermal adaptation of southern migrants to the district heating environment in the severe cold area, China: a longitudinally traced investigation

Preference for thermal environments is affected by the thermal histories on their own. A deeper understanding of human thermal adaptation to create comfortable and energy-saving environments is desired. To study the differences in thermal responses of southern migrants and northern locals to district heating environments, a longitudinally traced investigation was performed in the severe cold area, China. 74 freshmen with different thermal histories were invited for six weeks in winter. Physiological parameters and thermal response votes were collected. Results showed that the most significant difference in the thermal neutral temperature between locals and migrants reaches up to 1.1°C, after acclimation, which decreases to 0.7 °C. Also, southern immigrants are not as sensitive to temperature changes as locals, but the gap is narrowing. Moreover, immigrants tended to wear lighter clothing at the same room temperature compared to natives, who were more flexible in adjusting their clothing. It was also observed that physiological and psychological adaptation processes were not synchronous. The humidity is the leading purpose of physiological discomfort for migrants. Physiological adaptation is a relatively slow process. It concluded that southern immigrants may take approximately 1 week to adapt to the thermal environment with district heating. However, they did not fully adapt to the humid environment until the 6th week. The findings have implications for understanding the mechanisms of thermal adaptation and creating comfortable built environments.