Some results of laser sensing of industrial emissions over Far Eastern cities of the USSR are presented. Spreading of stack plumes has been tracked at distances to 22 km from the sources. It was shown that the spreading has a jetlike character. It was also revealed in this study that when the plumes reach the upper boundary of temperature inversion they balance around this level. In some cases the breakthroughs of the plumes through the inversion layer were observed due to convective air flows.