EAGER: Depth Sensitive Thermography for Mapping Temperatures of Our Environment

Mapping the distribution and evolution of heat in the atmosphere is a critical endeavor in diverse fields such as meteorology, climate science, and urban studies, especially in a time marked by climate change. However, current methods of measuring temperatures fall short of providing comprehensive information. For instance, weather stations or radiosondes take point or line measurements respectively, which may not be representative of temperatures over an entire city, while scanning LIDAR systems take line or 2-dimensional measurements at a slow pace and high costs. To address this issue, this project suggests a novel depth sensitive thermography (DST) concept, which harnesses the atmosphere’s varying opacity in the thermal infrared wavelengths to survey air temperature profiles in 3D space over ~1-10 km scales, and in time, thus revealing the distribution and dynamics of temperature (and potentially other meteorological variables) in the atmosphere. This project will explore the physical mechanisms of DST, and create the first proof-of-concept DST-imager and explore its utility for temperature measurements and meteorological observations. If successful, this research will yield a new way to profile air temperatures over very large scales, representing a major advance in thermal imaging and sensing, and potentially enable previously unthought applications in meteorological monitoring and research, thermal mapping, and tracking of objects (e.g. forest fires, or in defense applications). The findings of this project will also be integrated into educational and outreach activities by the PI and co-PI to disseminate scientific knowledge and public awareness of DST, and on a different front, potentially lead to the creation and commercialization of unique DST-capable devices originating in the US. Thermography is traditionally restricted to mid or longwave transmission windows of the atmosphere to bypass its opacity in other wavebands, and yields flat images. This project will be the first to utilize the atmosphere’s broadband, spectral transmittance across different wavebands to image and map its temperature distribution (and potentially dynamics) in 3D over 1-10 km scales – a novel and transformative concept that breaks from traditional thermography in terms of the underlying science, optical/radiometric design, and applications. As the first exploration of depth-sensitive thermography, the project will explore scientific and engineering questions such as: What physical limits do the atmosphere and weather impose on DST? How are spectral and spatial resolutions related? What detection systems – ranging from microbolometers to interferometric systems – would offer the spectral/spatial and temporal resolutions needed for advanced meteorological measurements? The findings will be used to design a DST-imager with sufficient spectral/spatial and temporal resolution for proof-of-concept atmospheric temperature profiling experiments, as well as atmospheric boundary layer measurements. As such, it will yield fundamental and technical insights into a novel radiometric method and its potential for meteorological measurements, potentially seeding a new area of research. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.