- Status: Orange.
- Interactive official hazard map (autotranslated), via Relief Web; En español
- USAID April 4th map (autotranslated) posted on May 18 at Relief Web.
- Links to webcams, public data, and other information.
- Update archive.
Update, June 19, 9:26 a.m., Pacific: The summit is clear and frosty at the moment, under a blue sky; here it is from a webcam viewing the volcano’s backside:
If you’re wondering about that obvious collapse scar, here is the field guide linked by Washington VAAC at their Ruiz page (see information links above), but it is very complicated geology — this layperson with some undergraduate training had a hard go working through it.
Pretty as a postcard, but enough ash — it doesn’t take much to mess up an aircraft’s innards — nevertheless is suspended in the air for 70 nautical miles from the summit for a VAAC advisory to be in effect:
Multiple such advisories have been issued over the last 24 hours, [LAYPERSON SPECULATION]which may have as much to do with improved weather conditions as with Ruiz’ activity, which SGC has noted in previous bulletins to be constant as well as with pulses of ash emission.[/LAYPERSON SPECULATION]
However, this is probably the reason for the current advisory:
https://youtu.be/hmz6FNWA8j0&rel=0
From a Tolima Civil Defense volunteer at around 6:30 a.m., local time.
Yesterday, TROPOMI noted SO2, too.
Meanwhile, schools are on break and the area around Pereira, capital of Risaralda state, is open for tourism (autotranslated).
Pereira appears on some of the hazard maps linked above. This region originally fell under the 15-km exclusion zone, but in late May the UNGRD exempted it. (Source, autotranslated)
Here’s today’s SGC bulletin, just issued (their emphasis):
Manizales, June 19, 2023 11:10 a.m.
From the monitoring of the activity of the NEVADO DEL RUIZ VOLCANO, the MINISTRY OF MINES AND ENERGY through the COLOMBIAN GEOLOGICAL SERVICE (SGC) informs that:
From 9:00 a.m. from yesterday (June 18) until the time of publication of this bulletin, the seismicity related to the movement of fluids inside the volcanic conduits has shown an outstanding increase compared to previous days. However, the values are below the maximum recorded in recent months. An important aspect that has been observed in the last few days is the increase in seismic signals associated with the activity of fluids that are sustained over time and are normally associated with the output of ash and/or greater intensity in the output of gases from the crater.
Regarding the seismicity associated with the fracturing of rock inside the volcanic edifice, this decreased in the number of earthquakes and seismic energy, compared to June 17. The earthquakes were low energy.
Regarding the surface activity in the volcano, the continuous and pulsatile emission of ash persists, confirmed through the web cameras used for volcanic monitoring and other external sources. The column of gases, steam and/or ash reached a maximum height of 1100 m measured from the top of the volcano and a preferential direction towards the northwest of the volcanic structure. Yesterday, on several occasions, and today in the morning, there was an ash fall in Manizales (Caldas). It is not ruled out that this phenomenon will continue to affect the city today if the emission of ash persists and if the direction of the wind is maintained towards the northwest.
Additionally, the variations in the degassing of sulfur dioxide and the output of water vapor from the crater to the atmosphere continued. There were no reports of thermal anomalies on the bottom of the Arenas crater, given the high cloudiness conditions at the time of capturing the image from the satellites, but this does not mean that they are not still present.
Finally, it is important to mention that the variations of the other monitored parameters are still minor.
Although in recent days the activity of the Nevado del Ruiz volcano has begun to show signs of decrease, it also registers some moments of increase with respect to previous days, and so, it is still unstable. The volcano has not returned to its normal levels of activity and, despite the decline in its activity, it could still erupt in a major way in days or weeks. As we have mentioned, on previous occasions, after presenting important changes in its activity, the Nevado del Ruiz volcano has shown a decrease in its activity before a major eruption. That is to say, first it registers a strong increase in its activity, then a considerable decrease and, subsequently, makes a major eruption.
Therefore, we reiterate that the activity of the Nevado del Ruiz volcano continues at ORANGE LEVEL, which indicates that there is a probability that in days or weeks there will be a larger eruption than it has made in the last 11 years (May 29 was the first minor eruption that this volcano made in its most recent eruptive process). To change levels and return to Yellow requires a prudential time where trends and patterns can be observed that allow inferring the possible decrease in activity, aspects that cannot yet be confirmed. For this reason, following the precautionary principle, the level of activity of the Nevado del Ruiz volcano will remain at LEVEL ORANGE. During this time, in the event of an acceleration of the processes that suggest an imminent eruption or the eruption itself, the level of activity will change to Red.
We recommend that the community remain calm, follow all the instructions of the Unit National for Disaster Risk Management (UNGRD) and local authorities, and be attentive to the information provided by the Colombian Geological Service on the evolution of the state of the volcano.
The COLOMBIAN GEOLOGICAL SERVICE will continue to monitor the evolution of the volcanic phenomenon and will inform in a timely manner about the changes that may occur.
For more information visit the following link:
https://www2.sgc.gov.co/Noticias/boletinesDocumentos/Forms/AllItems.aspx
Featured image: Ric Photography/Shutterstock
Flight To Wonder 