As urban areas continue to expand, there is an increasing focus on enhancing the comfort of outdoor thermal conditions.

In this study, summer discomfort index (SDI) maps were created for Seville, Barcelona, in Spain and Tetuan in Morocco .
Both temperature and humidity, which are crucial components in determining thermal comfort and discomfort, are taken into account by SDI.

The calculations used substituted air temperature with land surface temperature data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and humidity from weather stations, which were then compared to thermal sensation votes (TSV) gathered from surveys given to the residents.
Land surface temperatures are normally higher than air temperatures, but the resulting maps offered a close representation of thermal comfort.

The goal was to evaluate the thermal comfort levels in the chosen cities and investigate the relationship between the remotely sensed (SDI) and the reported thermal perception by the residents. We aimed to gain insights into urban thermal environments and their effects on human perception by integrating remote sensing data and subjective (TSV).

The visual maps offer an easily readable representation of thermal comfort and discomfort and can assist designers in creating better outdoor spaces that are tailored to the needs and comfort levels of residents in each unique city.

The method involved gathering and examining MODIS land surface temperature data, processing it, and calculating each city's (SDI) values. Votes on thermal comfort (TSV) were collected through a seven scale questionnaire-based survey and represented residents' individual experiences and perceptions.

The findings provide valuable insights into the thermal conditions and comfort levels experienced by residents during summer in Seville, Barcelona, and Tetuan. Remote sensing data enabled the creation of spatially explicit (SDI) maps, facilitating a detailed assessment of thermal comfort variations within and between the studied cities. Comparing the remotely sensed (SDI) with subjective (TSV) contributes to a comprehensive understanding of agreement or divergence between objective measurements and human perception.

By highlighting the importance of integrating remote sensing techniques and subjective assessments for evaluating thermal comfort in urban areas, this research advances the field of urban climate studies and its results have implications for urban planning, design, and the development of strategies to enhance thermal conditions and well-being of city residents.