Satellite imagery showed just a small plume of ash, indicating that the eruption would pose little threat to aviation. Infrared imagery confirmed that the cloud mainly consisted of gasses, which jet aircraft must also avoid. By means of the FLEXPART 3D simulation and infrared imagery, it was possible to trace the volcanic gas cloud from start to end: It went up to about 11000 meters, tracked up the Red Sea, before it was caught in the Subtropical Jet stream, then tracked all the way to Japan, a journey of about 8000 km.
A 3D simulation of the movement of the volcanic gas cloud was undertaken using NILU’s state-of-the-art particle dispersion model FLEXPART. The model will help the aviation authorities with their warning systems. Volcanic gas clouds spread rapidly in the atmosphere and can damage passenger jet aircraft and interrupt busy airways. This also illustrates how remote sensing data and models can help us visualize the movement of volcanic gas clouds. Andreas Stohl at NILU originally developed the FLEXPART model for research on long-range air pollution, which still is an important use of the technology.
The simulation can be viewed here: Jebel al-Tailr SO2 Eruption. Sabine Eckhardt at NILU developed the volcanic gas cloud model.
The simulation shows the 3D structure of the cloud (in shades of red), the vertical gas column projected onto the Earth’s surface (in shades of blue) and the horizontal columns (along the axis of the cloud and at right angles to the axis – black contours). The model shows that the cloud moved up the Red Sea and then traveled quickly eastwards towards Russia and eventually Japan – in agreement with the satellite images.