i take it they are raster photo images ?
siganl.gdas. = "Global Data Assimilation System" from NOAA
A guess, something from a GIS program
if so the terminal version of Gmic can read them
LSB/MSB 16 bit singed and unsinged
gmic is 32 bit float native
http://gmic.sourceforge.net/
or
use a geographic data program like GDAL
most Distros have gdal in the repos
http://www.gdal.org/
"gdal_translate " is the program in the software suite
a link to the original source for the file "siganl.gdas.2011022000"
would help
i do a lot of work with the imaging data from Cassini