The supergranulation observation data is comprised of four FITS files:

reference_vz_xyt.fits
supergranule_vz_xyt.fits
supergranulex2_vz_xyt.fits
uniform_vz_xyt.fits 

Each file is a {x,y,t} cube of vz velocity "observations" at 200 km above the photosphere, sampled at 60 second periodicity.  Horizontal domain is 100 Mm in the x and y dimensions.  

+ The 'reference' file contains data from a quiet sun simulation with Model S background and NO imposed background flows.  
+ The 'supergranule' file contains data simulation with the supergranule background flows imposed and using the same Model S background properties and periodic forcing.  
+ The 'supergranulex2' file contains data from a simulation where the magnitude of the supergranule flows have been multiplied by a factor of two - for testing linearity of the inversion methods.  
+ The 'uniform' file contains data from a simulation with a uniform Vx = 100 m/s background flow.