Five different instruments were used in coordinated multiple experiments to measure atmospheric turbulence. C sub n squared, the optical refractive structure constant, was measured by thermosondes, UHF radar, stellar scintillometer, and aircraft mounted micro-thermal probes. Presented here are the results of 19 rawinsode flights. Also comparisons of eight thermosonde/radar profiles, one radar, scintillometer, thermosonode profile, and several aircraft profiles are presented. For the scales discussed here, good agreement is shown between radar, thermosonode, and scintillometer data. Worse agreement is obtained from aircraft measurements. A diurnal shift in the C2 profile is noted but no tropopause enhancement is found.