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Turbulent fluctuations of the energy density of broadband pulsed Laguerre-Gaussian beams are studied based on numerical solution of the parabolic wave equation for the complex spectral amplitude of the wave field by the split-step method. It is shown that in the regime of strong scintillations, the relative variance of energy density of the pulsed beams can take values smaller than unity, in contrast to the strong scintillation index of the continuous-wave beams, which tends to unity with increasing the turbulence strength. The level of residual spatial correlation of the energy density of pulsed beams exceeds that for the continuous-wave beams. It increases with shortening of the pulse duration and increasing of the refractive turbulence strength.

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The paper presents experimental data on determining a level of turbulence over a heated metal surface in the saturated turbulence regime, which cannot be explained by the classical Kolmogovov-Obukhov theory. A spectral behavior of temperature fluctuations is studied. Based on the calculated data of the structural function and the spectrum of temperature fluctuations, the level of turbulence over the heated surface is determined along the height. Estimation of the outer scale of turbulence showed that in the center of the metal surface the outer scale increases with height. At the surface boundary, cascade generation-dissipation of vortices is observed.