Fig. 4: Reconstruction of plume trace gas concentrations.

a-1 Plume signals collected through the filter @310 nm. a-2 Plume signals collected through the filter @330. a-3 Difference in signals between filters @310 nm and @330 nm. b-1 SO₂ concentrations in the plume measured by the hyperspectral camera. b-2 Reconstruction of the plume with SO₂ distributions