Modeling temperatures of wildfires and volcanic lava flows necessitates
measurements of emitted radiance at 4 μm wavelength. The 60 m
spatial resolution of the HyspIRI TIR sensor will allow more detailed
analysis of high temperature phenomena, but also makes saturation of
the 4 μm channel more likely than for previous coarser resolution sensors.
Realmuto et al. (2015-in this issue) review temperature retrievals
from a variety of satellite and airborne sensor data, and provide new
analyses of data acquired over fires and lava flows. They recommend a
1200 K saturation brightness temperature for the 4 μm channel, which
is unlikely to saturate for wildland fires and lava flows filling an instantaneous
field of view. The tradeoff for a higher saturation threshold is a
higher noise equivalent delta temperature at background temperatures,
but other HyspIRI TIR sensor channels will provide lower saturation
thresholds and higher sensitivity