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The urban thermal environment is a complex phenomenon, and its effects can be manifested in various aspects, such as the urban heat island intensity (UHII), outdoor thermal comfort, and building energy demand. In this study, the effects of different early planning strategies on these three aspects were evaluated at the neighborhood scale. The central city of Guangzhou, China, was used as an example, typical neighborhoods were delineated using the local climate zone system, and the Urban Weather Generator (UWG) model was used to simulate the thermal environment. A combination of remote sensing, visual interpretation, field studies, and social perception were used to obtain the environmental indicators and input parameters. The results showed that the building height, building density, and wall-to-plan area ratio are the most influential factors on the UHII, the universal thermal climate index (UTCI), and the cooling energy demand (CED) with the PAWN index above 0.2. The change in spatial and temporal variability at the neighborhood scale can have different levels of impact on UHII, UTCI, and CED. Therefore, targeted planning strategies that consider multiple factors that influence the thermal environment must be used to achieve the best results in different urban areas. • The methodology enables quick and simple thermal environment assessments. • Thermal environmental phenomena were assessed by the Urban Weather Generator model. • Sensitivity analysis evaluates thermal environment impacts of planning strategies. • Building height, density, and wall-to-plan ratio greatly impact thermal environment. • Targeted thermal mitigation strategies are needed for different neighborhoods. [ABSTRACT FROM AUTHOR]

Thermal comfort of outdoor pedestrians is a crucial factor affecting the quality of urban life. The quantification of the thermal radiation environment near the ground of an urban street canyon is essential for understanding the thermal comfort of pedestrians. Most studies on the thermal comfort of outdoor pedestrians did not consider the dynamic changes in the thermal radiation on the pedestrian route. The mean radiant temperature for a given location does not adequately represent the effect of non-uniform thermal radiation on the human body. In this study, a simulation method is proposed to investigate thermal radiation experienced by pedestrians in street canyons. We obtained the main parameters affecting the dynamic and non-uniform thermal radiation in the central district of Guangzhou. The results show that an exponential function describes the relationship between the time a pedestrian remains in the post-change environment and the solar elevation angle (h s) as the pedestrian travels through sunlight and shadow areas. A quadratic function describes the relationship between a change in the temperature of thermal radiation and the h s and between the sunlight-shadow frequency and h s. Non-uniform thermal radiation is attributed to the direct shortwave radiation (SW dir) in sunlight areas. The different directions of SW dir irradiating the human body cause a temperature difference in the non-uniform thermal radiation between different parts of the human body. [Display omitted] • Three parameters were proposed to measure the dynamic thermal radiation of pedestrians: f 300 , Δ MRT t , and τ. • The solar elevation angle h s significantly influenced the dynamic thermal radiation. • The vector of direct solar radiation significantly influenced the degree of non-uniformity of thermal radiation Δ MRT s , in each body part. [ABSTRACT FROM AUTHOR]