The report of OV Manizales of 08.10 specifies that the red tones perceived on the images of the emission of ash from Nevado del Ruiz take 5 october are in fact optical effects of sunlight. An emission of ash indicates not an imminent eruption. The alert level remains Amarillo / behavior change in volcanic activity.
Nevado del Ruiz - emission of ash and light effects - photo RCN Radio / via Shérine France
Nevado del Ruiz - 05/10/2016 - photos taken with and without the effects of sunlight - doc. SGC Manizale
Nevado del Ruiz - 05/10/2016 - photos taken with and without the effects of sunlight - doc. SGC Manizales
Note that on October 7, at 3:34 p.m. local, a volcano-tectonic earthquake, combined with the fracturing of rocks, was recorded at 4,400 m north of Arenas crater; it is of local magnitude 4.4 and hypocenter located at a depth of 5.4 km.
Source: SGC - Volcano Observatory in Manizales.
The KVERT changed twice in two days the alert level of aviation of Karymsky: yellow, October 7 at 11:16 p.m. GMT and orange, October 8 at 1:34 UT.
Based on satellite data of October 7, the volcano seems to have increased. A gas plume moderately loaded in ash extends for about 100 km to the SE of Karymsky.
Terra Modis Data of October 8 mention an ash plume drifting 78 km to the SE of the volcano, and a gas and steam plume containing the ashes of 388 km SE of the volcano.
It is not specified the origin for the observed plumes ... Consecutive of an eruption, or due to remobilization of previously deposed ashes ? To be continued.