Abstract
Estimates of the level of turbulence C2n and the inner scale of turbulence λ0 are obtained from measurements of the spatial covariance of laser scintillation in weak scattering conditions. Boundary layer turbulence is widesense nonstationary over time scales of <1 min but becomes locally wide-sense stationary on time scales of 2 min. The interpretation of the measurements is very sensitive to the form of the turbulence spectrum in the dissipation region.