Huang Junwang, Shen Shi, Zhao Min, Cheng Changxiu
Key Laboratory of Environmental Change and Natural Disaster Beijing Normal University Beijing China.
State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing China.
Geohealth. 2023 Jan 1;7(1):e2022GH000725. doi: 10.1029/2022GH000725. eCollection 2023 Jan.
Outdoor thermal comfort (OTC) is critical for public health, labor productivity, and human life. Growing extreme heat events caused by climate change have a serious impact on OTCs, especially in urban areas. Quantitatively characterizing and evaluating the spatiotemporal changes in OTCs are essential, and more applications are needed in urban agglomerations. Therefore, taking the Beijing-Tianjin-Hebei (BTH) urban agglomeration as the study area, this study aimed to quantitatively assess the summer regional OTC from 1981 to 2020. First, the Universal Thermal Climate Index (UTCI) was used as the indicator of daily thermal stress, and then a Composite Thermal Comfort Score was proposed to evaluate the long-term, summertime, regional OTC considering the extent, duration, and intensity of daytime and nighttime thermal stress. The results showed that (a) the increase in UTCI (0.32°C/10a at daytime and 0.21°C/10a at nighttime) and heat stress frequency (0.88 at daytime and 0.39 d/10a at nighttime) were manifested over BTH, indicating a worse OTC. Spatial and temporal heterogeneity was also demonstrated. (b) The general OTC showed a decreasing north-south gradient pattern. At daytime, the northern mountainous zone presented the best OTC, the southern plain zone, especially Hengshui, Langfang, and Cangzhou, showed the worst. At nighttime, the mountain-plain transition zone showed the best OTC, the northern mountainous zone showed the worst since more cold stress occurred. Our findings will be useful in informing climate change adaptation strategies to ensure urban resilience as extreme heat increases in the context of climate change.
室外热舒适性（OTC）对公众健康、劳动生产率和人类生活至关重要。气候变化导致的极端高温事件不断增加，对室外热舒适性产生了严重影响，尤其是在城市地区。定量表征和评估室外热舒适性的时空变化至关重要，并且在城市群中需要更多应用。因此，本研究以京津冀（BTH）城市群为研究区域，旨在定量评估1981年至2020年夏季的区域室外热舒适性。首先，将通用热气候指数（UTCI）用作每日热应激指标，然后提出了综合热舒适评分，以考虑白天和夜间热应激的程度、持续时间和强度来评估长期、夏季、区域室外热舒适性。结果表明：（a）京津冀地区UTCI升高（白天为0.32°C/10年，夜间为0.21°C/10年）和热应激频率增加（白天为0.88，夜间为0.39天/10年），表明室外热舒适性变差。还表现出时空异质性。（b）总体室外热舒适性呈现出南北递减的梯度模式。白天，北部山区的室外热舒适性最佳，南部平原地区，尤其是衡水、廊坊和沧州，表现最差。夜间，山地-平原过渡带的室外热舒适性最佳，北部山区由于更多冷应激的发生而最差。我们的研究结果将有助于为气候变化适应策略提供信息，以确保在气候变化背景下极端高温增加时城市的恢复力。
