About two hours ago, there was a big explosion (should be able to get the time-lapse video within an hour):
A las 21:23 h el #Popocatépetl presentó una exhalación con contenido de ceniza y lanzamiento de material incandescente sobre las laderas del volcán. La ceniza se dispersó al oeste. Semáforo🚦 en #AmarilloFase2 pic.twitter.com/IbtaxOOrzH
— PC Estatal Puebla (@PC_Estatal) February 23, 2020
Since then, there has been tremor and ash emission reported:
⚠️Se exhorta a la población a respetar el radio de seguridad de 12 km.
— PC Estatal Puebla (@PC_Estatal) February 23, 2020
The webicorder is intense, too. The explosion happened at 21:23 local time, and the most intense tremor is before that. Then it became more episodic and a bit lighter, but still more intense than usual.
The alert level is still Yellow Phase 2, but obviously this is more than a puff. Will just have to wait and see what the volcano does and also what the experts report while monitoring it.
I’ll stick this at the top of the blog and use it as this week’s Sunday Morning Volcano before putting it into the live blog after this episode is over.
Update, from about 21 minutes ago – WOW! (not a new explosion, just video of the one at 21:23 — sorry about the music):
22 Febrero 2020 pic.twitter.com/ZgMAot2t6q
— TULAN_NETWORK (@NetworkTulan) February 23, 2020
That was mostly big material (look how long it took for the incandescence to fade) and it went a LONG way. That, kiddies, is why there is a 7.5-mile no-go zone around Popocatepetl right now!
Update, 10:08 p.m., Pacific: Here’s the time-lapse — frankly, it looks much less world-shattering in these views.
No wonder they kept the alert steady at Yellow Phase 2. Still, though — that was a powerful explosion. Am guessing that a sizable chunk of rising magma got stuck, gases quickly built up, and BOOM!
My question: Can this turn into the new normal, i.e., are we going to see more great volumes of very gassy/hydrated magma coming up?
Update, February 23, 2020, 8:12 a.m., Pacific: One more big boom not long after this time lapse starts at midnight and that was all — thus far. (CENAPRED is likely to include close-up video of it, so I’ll wait until their update to include one here.)
Popo also greeted the dawn with some spectacular “puffs.” But some steam (white clouds) shows up now upon checking the San Nicolas de los Ranchos (SNR) webcam. And, probably not coincidentally, there has been a change in the webicorder patten, back to the old “loose perm wave” kind of pattern. (What should we call the tremor pattern before the first big blast last night — a punch perm, perhaps.)
Look for the second explosion towards the end of the 00:00 lines. This time around, there was no intense tremor before it — quite the opposite, actually. As time passed after that second explosion, the tracing went back to that rather bland pre-blast pattern until a little after 2:30. I can’t put it into technical terms, of course, but the webicorder tracing looks like Don Goyo got something caught in its throat again, but this time as it hacked and gagged, the blockage shifted and cleared. That current “wavy perm” pattern appears — to this layperson, anyway — very similar to Popocatepetl’s present baseline.
When I have some time, after the cat books are out, I’m going to try to find papers about the role of water in Popocatepetl’s activity.
Anyway, not that a lay interpretation means anything, but I think this particular explosive episode is over now (unless another batch of gassy, hydrated magma comes up).
Update, February 23, 2020, 9:22 a.m., Pacific: Uh, there are other things that can happen when a volcano clears its throat.
For the last several minutes, while I’ve been watching the SNR livestream, Popo has been erupting ashy/steam plumes — that stuff is hot, too: the convection in the cloud now continues long after it has left the vent, as you typically do see in an eruption.
Update, February 23, 2020, 10:10 a.m., Pacific: CENAPRED’s report is out and describes the explosions as moderate. They did include a video of the second explosion last night, but I’d rather focus on what the volcano is doing now — activity up there, seen through the SNR livestream, is still at a low level (in that the wind does blow away the plume), but it is close to if not already constant.
Here is a time-lapse of this morning’s events — the more constant activity comes near the end of it:
These videos are posted several times a day here.
No change in alert level (and there wouldn’t be, as long as the volcano’s emissions are this low); this must be stressing a lot of people out.
I’ve been thinking back to the last overflight on the 18th to recall how much of the summit crater was filled. This material is mostly falling back into the crater and when that fills up, it will have nowhere to go but down the slope as pyroclastic flows (of limited runout). That, in turn, will become mud flows in wet weather.
Here are the February 18 overflight videos:
This was before the additional tephra of the last several days. It looks like there’s still plenty of room, but there is a lot of material presently being added at a fast pace.
Update, February 23, 2020, 11:02 a.m., Pacific: If you’re watching this live on the SNR stream, you may have noticed a big white weather cloud trying to form on the right. That typically happens at Popo around this time of day — often the summit is socked in until late afternoon or even into the evening, and then it clears.
Not today, though. The cloud wanted to — I noticed some little streamers condensing off to the left, which is how this type of cloud spreads around the mountain. But too much warm air is coming from the volcano, I suspect: warm air holds more moisture; clouds appear when moisture condenses out of cooler air.
Also the convection up there seems to be really roughing up the weather cloud’s internal structure, perhaps even tearing it apart.
Otherwise, eruptive activity appears to be the same. Haven’t spotted any pyroclastic flows from the San Nicolas de los Ranchos side.
Update, 11:37 a.m., Pacific: Looks like the constant low-level ash ventilation is, at least, paused — there’s just the usual rising steam/gas/very light ash plume visible — they have zoomed in the SNR cam, probably to see it. Still watching. The webicorder shows a lot of tremor since about 11 a.m. Popocatepetl time:
A drop in activity is not necessarily a good thing during an eruption.
Update, 12:18 p.m., Pacific: Well, there was a small “puff” a little while ago, but it only briefly dispersed the weather clouds that are gathering around the summit. More importantly, the webicorder now seems to be going back into that “loose perm wave” tremor pattern. Will sign off on this now until or if something big happens again today — if not, will just carry on at the regular live blog.