ABSTRACT
The data from spaceborne infrared (IR) sensors have been used to detect and monitor volcanic eruptions from the earliest days of the satellite era. The early studies focused primarily on hot spot detection and temperature estimates based on broad-band thermal infrared (TIR) radiance measurements. The advent of multispectral TIR sensors led to more sophisticated and accurate techniques for estimating temperatures as well as techniques for estimating the SO2 content of volcanic plumes. Future missions hold promise for further development. For example, the Surface Biology and Geology – Thermal Infrared (SGB-TIR) mission is proposed to carry the Observing Terrestrial Thermal Emission Radiometer (OTTER) instrument. OTTER is designed to acquire mid IR – TIR radiance measurements in eight spectral channels with an unprecedented combination of fine spatial resolution (60 m at nadir) and revisit frequency or cadence (3-day revisit at equator). In this chapter, we describe the foundations of our procedures for mapping volcanic SO2 plumes and thermal anomalies, using proposed OTTER capabilities as a case study.
