Systems and methods for remote detection of volcanic plumes using satellite signals. The invention solves the problem of remotely detecting volcanic plumes, including those embedded in clouds, by providing a system that can be installed onboard a mobile platform, such as an aircraft, a satellite, a weather balloon, a ship or a buoy. The volcanic plume detection system tracks RF signals (such as GPS signals from satellites) arriving at the mobile platform, and issues an alert or warning when characteristics of the RF signals indicate the likely presence of a volcanic plume in the monitored space. More specifically, the system in accordance with one embodiment utilizes the refractive properties of hydrogen sulfide (H2S), a gas that is abundant in nearly all volcanic eruptions, to infer the presence of a volcanic plume.