We report the experimental investigation of a stimulated rotational Raman scattering effect in long air paths on SG-IQ TIL, with a 1053nm, 20-cm-diameter, linearly polarized, ins flat-topped laser pulse.An intense speckle patte of near field with thickly dotted hot spots is observed at the end of propagation with an intensity-length product above 17TW/cm.The Stokes developing from the scattering of the laser beam by quantum fluctuations is characterized by a combination of high spatial frequency components.The observed speckle patte with smalldiameter hot spots results from the combination of the nonlinear Raman amplification and the linear diffraction propagation effect of the Stokes with a noise patte arising from the spontaneous Raman scattering.A new promising suppression concept based on the special characteristic of the Stokes, called active and selective filtering of Stokes, is proposed.