AbstractThe intensity of acoustic backscatter from a monostatic acoustic sounder is used to compute the profile of the temperature structure parameterC T2. The average value ofC T2in low‐height turbulent stable layers (temperature inversions) is used to infer the local potential‐temperature gradient. The estimates of temperature jump in the first height inversion at the top of the unstable atmospheric boundary layer (ABL) are compared with the direct measurements of the temperature profile by a tethered balloon, and the indirect estimation from the wave period of the waves present on the inversion. The agreement of the estimations with the direct measurements is satisfactory (at least a 0.4 degC accuracy). Also, the‐4/3 similarity law of theC T2profile in the unstable ABL is used to obtain estimates of the surface heat flux,Qo. The comparison of these estimates of Qowith eddy correlation measurements shows the high accuracy of this method. This direct connection of theC T2profile withQocan also be used to calibrate the backscat