Elevated temperatures in urban centers have become a common problem in cities around the world. However, the climate problems in suburban areas are equally severe; there is an urgent need to find zero-carbon ways to mitigate this problem. Recent studies have revealed the thermal performance of vegetation, buildings, and water surfaces. They functioned differently regarding the climate at different periods of the day. Accordingly, this study synthesizes remote sensing technology and meteorology station observation data to deeply explore the differences in the role of each climate-influencing factor in the suburban areas of Chengdu. The land surface temperature (LST) and air temperature (T_a) were used as thermal environmental indicators, while the normalized difference vegetation index (NDVI), normalized difference water index (NDWI), normalized difference built-up index (NDBI), and altitude were used as environmental factors. The results showed that the relevant influences of the environmental factors on the climate in the sample areas were significantly affected by the time of the day. The NDVI (R² = 0.5884), NDBI (R² = 0.3012), and altitude (R² = 0.5638) all showed strong correlations with T_a during the night (20:00–7:00), which gradually weakened after sunrise, yet the NDWI showed a poorer cooling effect during the night, which gradually strengthened after sunrise, reaching a maximum at 15:00 (R² = 0.5012). One reason for this phenomenon was the daily weather changes. These findings facilitate the advancement of the understanding of the climate in suburban areas and provide clear directions for further thermal services targeted towards people in different urban areas.

Thermal comfort studies are paramount in enhancing future urban living conditions, and hemispherical photography has emerged as a widely employed field measurement technique in outdoor thermal comfort research. This comprehensive review systematically analyzed 142 outdoor thermal comfort studies conducted over the past decade using hemispherical photography methods, revealing that its primary application lies in objectively describing environmental information and constructing associated indices. In contrast, the number of studies focusing on subjectively assessing environmental factors remains relatively low; however, it is rapidly increasing due to its demonstrated effectiveness and convenience compared to other methodologies within this domain. Overall, despite certain limitations, such as higher labor costs and limited temporal/spatial coverage when describing environmental information, hemispherical photography still retains its advantage of providing accurate data acquisition for outdoor thermal comfort research. In recent years, advancements in mobile measurement tools and techniques have enhanced the richness and versatility of acquired information while leveraging the image specificity inherent to hemispherical photography, which continues to play a pivotal role in subjective assessments related to human perception of outdoor thermal comfort.