Abstract People are exposed to multiple stimuli in urban environments, but most studies have investigated the unimodal effect of thermal and visual conditions on human comfort perception. It remains unclear whether the cross-modal effect found in indoor multisensory studies applies to outdoor environments. To understand the cross-modal effect of thermal and visual conditions on outdoor comfort perception, we conducted a thermal comfort survey (n = 4304) in Guangzhou and Zhuhai (September 2018). We used the Universal Thermal Climate Index (UTCI) heat stress classification and sky conditions to stratify our results. The thermal sensation vote was positively correlated with sun sensation vote. There was a significant interaction between UTCI heat stress conditions and sunlight preference vote on thermal comfort vote. The sun sensation (brightness) and sunlight preference vote had a cross-modal effect on thermal sensation and thermal comfort vote under various UTCI heat stress conditions. Under extreme heat stress, respondents’ thermal sensation did not differ significantly between different sun sensation and sunlight preference groups. Thermal sensation, preference and comfort vote had a cross-modal effect on sun sensation and sunlight preference under different sky conditions. Under partly cloudy conditions, sun sensation did not differ significantly between certain thermal sensation and preference groups. A theoretical framework is provided to explain the cross-modal effect between thermal and visual perception. Our findings suggest outdoor thermal discomfort can be alleviated by improving visual comfort and vice versa. Therefore, urban design should consider the combined effect of visual-thermal stimulants in optimizing overall pedestrian comfort and promoting urban liveability.

中文翻译：

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热和视觉条件对室外热和视觉舒适感知的跨模态影响

摘要 人们在城市环境中会受到多种刺激，但大多数研究都研究了热和视觉条件对人类舒适感的单峰效应。目前尚不清楚室内多感官研究中发现的跨模态效应是否适用于室外环境。为了了解热和视觉条件对室外舒适度感知的跨模态影响，我们在广州和珠海（2018 年 9 月）进行了热舒适度调查（n = 4304）。我们使用通用热气候指数 (UTCI) 热应力分类和天空条件来对我们的结果进行分层。热感觉投票与太阳感觉投票呈正相关。UTCI 热应激条件与日光偏好投票对热舒适度投票之间存在显着的相互作用。在各种UTCI热应激条件下，阳光感觉（亮度）和阳光偏好投票对热感觉和热舒适投票具有跨模式影响。在极端热应激下，不同日光感和日光偏好组之间受访者的热感没有显着差异。在不同的天空条件下，热感觉、偏好和舒适度投票对阳光感觉和阳光偏好具有跨模态效应。在部分多云的条件下，某些热感觉和偏好组之间的阳光感觉没有显着差异。提供了一个理论框架来解释热感知和视觉感知之间的跨模态效应。我们的研究结果表明，可以通过提高视觉舒适度来缓解户外热不适，反之亦然。所以，