“…Although the value of ground‐based (handheld or tripod‐mounted) thermal imaging and thermal infrared thermometers in volcanology has long been recognized [e.g., Decker and Peck , 1967; Shimozuru , 1971; Birnie , 1973], only recently has the routine use of ground‐based thermal measurements become widely reported. In recent years, ground‐based thermal infrared measurements of active volcanic features have been used to achieve the following: (1) recognize magma movements within the central conduits, detect the upward movement of shallow feeder dikes and track eruptive activity [ Calvari et al , 2003; Harris et al , 2003]; (2) measure the thermal and rheological properties of active basaltic lava flows, lava tubes and silicic (block) lava flows [ Flynn and Mouginis‐Mark , 1994; Hon et al , 1994; Harris et al , 2002; Kauahikaua et al , 2003; Wright and Flynn , 2003; Andronico et al , 2004]; (3) analyze the evolution of fumarole fields [ Harris and Maciejewski , 2000], active eruption plumes [ McGimsey et al , 1999; Dehn et al , 2002; Kaneko et al , 2002; Matsushima et al , 2003], strombolian activity and persistent degassing [ Harris et al , 1996; Ripepe et al , 2004]; (4) obtain effusion rate for active lava flows [ Harris et al , 2005]; (5) detect potential failure planes on recently formed cinder cones [ Calvari and Pinkerton , 2004] and fractures developing just before flank collapse at active volcanoes [ Bonaccorso et al , 2003]; and (6) analyze active lava lakes [ Flynn et al , 1993; Oppenheimer and Yirgu , 2002]. …”