A laser holography interferometer is applied to investigate heat and mass transport phenomena around the pseudo-critical line of supercritical artificial air with a composition of 79% nitrogen and 21% oxygen. In a previous study, we successfully observed the heat transport phenomenon, the piston effect, around the pseudo-critical line of nitrogen. The same experimental set-up is applied to the supercritical artificial air, which is a compressible binary mixture fluid. We attempt to suppress the generation of natural convection, and successfully observe the heat and mass transport phenomena, which are the soret effect and the piston effect, respectively. Here, we discuss these effects observed in the supercritical artificial air. (c) 2005 Elsevier Ltd. All rights reserved.