“Plume of unknown etiology” moving over Alaska

McIDAS images of GOES-11 0.65 µm visible channel data (above; click image to play animation) showed an interesting “dark plume” feature that was moving in an arc from far northeastern Russia, across the East Siberian Sea and Chukchi Sea, and finally over far northwestern Alaska on 16 March – 17 March 2011.

When viewed from a more western angle using MTSAT-2 0.73 µm visible channel images (below; click image to play animation), the plume feature (which can be seen moving over far northwestern Alaska in the upper right portion of the images) also exhibited a darker appearance, similar to that seen on the GOES-11 visible imagery. This darker appearance was due to backward scattering of light from the particles within the plume.