These files are calculations of the hourly solar
irradiance at the surface, based on observations
by the METEOSAT.  The file naming convention is:
       
              esDDMMYYsxx.fis

where DDMMYY is the date and xx = "slot number"
Mean time (UT) is obtained from the slot number over 
the ASTEX region by the formula: 

                  UT = (xx/2) - 0.17


These files are: I2 pixels, 376 pixels/row, 326 rows.  Each pixel
has a spatial resolution of 0.04 degrees.

The header of each file claims there are two channels, although
the provided documentation states that there is only one channel
per file.

The units are: flux [tenths of Joule/cm^2]