Figure 6. A “pseudogram,” a coarse echogram generated by the glider, highlights the scattering layer that the glider encountered between 50-80 meters (164-262 feet) depth. Green corresponds to stronger sound scattering, grey areas indicate the part of the water column where the glider did not detect any scattering during its descent. When the glider surfaces, it transmits this “pseudogram” via satellite to researchers to help determine where the scattering layers are. At the end of a mission the glider is retrieved and the high-resolution raw data can be downloaded.