Kizimen Volcano, which erupted for the first time in 81 years in December 2010, continues to emit gas and ash in November 2012. Because the region is so remote, the information gathered from remote sensing satellites is an invaluable aide to monitoring activity at Kamchatka’s active volcanoes. But when gas rises in a cloud-covered sky, true-color imagery often does not lend enough contrast for easy viewing of the event. In that case, false-color images, which use a different combination of bands gathered in the same fly-over, can prove helpful.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured data as it flew overhead on November 1, 2012. The top image, which is created from bands 1, 4 and 3, is a true-color image. In this image, the plume that rises from Kizimen and blows strongly to the northwest is visible – but is very indistinct as the light colored plume blends well with the white clouds and white snow.Rolling over this image shows the same image, except in false-color. Bands 1, 7 and 2 have been combined to help separate pale, gaseous volcanic emissions from white cloud. In this combination, land appears green, snow appears bright orange and cold clouds are white with a pale orange tint. The warm volcanic plume, which now is very easy to visualize, remains bright white.