The article discusses the use of thermal remote sensing in studying urban climates, focusing on the urban heat island (UHI) effect. It reviews progress in addressing methodological questions raised by Roth et al. (1989) regarding the application of thermal remote sensing to urban areas. While some progress has been made, thermal remote sensing of urban areas has been slow to advance beyond qualitative descriptions and simple correlations. The difficulty lies in using qualitatively based land use data rather than fundamental surface descriptors. Advances in satellite sensors, surface representations, and portable thermal scanners are expected to improve urban thermal remote sensing. The review emphasizes the importance of proper definitions in thermal remote sensing applications. It highlights the need for better understanding of urban surface characteristics, such as surface geometry and thermal properties, to improve the accuracy of thermal remote sensing data. The article also discusses the relationship between satellite-derived surface urban heat islands and those measured in the air, noting that direct comparisons must consider differing source areas. It concludes that detailed, fully coupled surface-atmosphere models are needed to accurately predict air and surface temperature differences in urban areas.The article discusses the use of thermal remote sensing in studying urban climates, focusing on the urban heat island (UHI) effect. It reviews progress in addressing methodological questions raised by Roth et al. (1989) regarding the application of thermal remote sensing to urban areas. While some progress has been made, thermal remote sensing of urban areas has been slow to advance beyond qualitative descriptions and simple correlations. The difficulty lies in using qualitatively based land use data rather than fundamental surface descriptors. Advances in satellite sensors, surface representations, and portable thermal scanners are expected to improve urban thermal remote sensing. The review emphasizes the importance of proper definitions in thermal remote sensing applications. It highlights the need for better understanding of urban surface characteristics, such as surface geometry and thermal properties, to improve the accuracy of thermal remote sensing data. The article also discusses the relationship between satellite-derived surface urban heat islands and those measured in the air, noting that direct comparisons must consider differing source areas. It concludes that detailed, fully coupled surface-atmosphere models are needed to accurately predict air and surface temperature differences in urban areas.