[1] Aerosols lofted to high altitudes by springtime Asian dust storms advect across the Pacific Ocean and, as recognized in recent years, regularly reach the western US. As part of our long-term cirrus cloud research program using remote sensing measurements, we have observed unusually warm cirrus ice clouds associated with transported Asian dust aerosols. The polarization lidar data presented for illustration here suggest that the dust particles, which are indicated to be especially active ice nuclei, can affect the formation and phase of clouds, and hence alter their radiative properties at least as far away as the eastern Great Basin of the US.