Xiaojiang Xu, Timothy P Rioux, John W Castellani, Scott J Montain, Nisha Charkoudian
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引用次数: 0
Abstract
Rising global temperatures, driven by climate change, pose a threat to human health and regional livability. Empirical data and biophysical model-derived estimates suggest that the critical environmental limits (CELs) for livability are dependent on ambient temperature and humidity. We use a well-validated, physiology-based, six-cylinder thermoregulatory model (SCTM) to independently derive CELs during sustained minimal, light, and moderate activity across a broad range of ambient temperatures and humidity levels and compare with published data. The activity and environments were considered livable if predicted core temperatures did not reach 38 ± 0.25°C within 6 h. The outcomes for minimal activity revealed CELs ranging from 34°C/95% relative humidity (RH) to 50°C/5% RH. Corresponding dry heat losses ranged from 14 to -72 W·m-2 (negative = heat gain) and evaporative heat losses ranged from 39 to 104 W·m-2. The wet-bulb temperature (Twb) at the CELs ranged from 33.3°C to 20.9°C. Activity shifted CELs toward lower temperatures and humidities. Importantly, our predicted CELs largely agree with observed livability CELs from physiology and those from a biophysical model. The physiology-grounded SCTM has utility for assessing the impact of climate change on regional livability.NEW & NOTEWORTHY This study is the first to use a physiology-grounded thermoregulatory model to predict critical environmental limits (CELs) above which human thermoregulatory capacity is exceeded. The model outcomes closely approximate empirically derived CELs, showing it is a strong model for estimating and preparing for the impact of climate warming on local, regional, and world human population livability and migration.
期刊介绍:
The Journal of Applied Physiology publishes the highest quality original research and reviews that examine novel adaptive and integrative physiological mechanisms in humans and animals that advance the field. The journal encourages the submission of manuscripts that examine the acute and adaptive responses of various organs, tissues, cells and/or molecular pathways to environmental, physiological and/or pathophysiological stressors. As an applied physiology journal, topics of interest are not limited to a particular organ system. The journal, therefore, considers a wide array of integrative and translational research topics examining the mechanisms involved in disease processes and mitigation strategies, as well as the promotion of health and well-being throughout the lifespan. Priority is given to manuscripts that provide mechanistic insight deemed to exert an impact on the field.