For transparent volcanic clouds, the
absorption of energy from the underlying
surface is greater in the band 4 region
than the band 5 region, due to a larger
refractive index for silicates in the band
4 region than in the band 5 region. This
results in a negative band 4 minus 5
brightness temperature difference.
This page maintained by Dave Schneider (djschnei@mt
u.edu)