The southwest monsoon over southern Luzon has weakened, and a thermal inversion has been in place for days, with PHIVOLCS issuing at least two special statements on the vog so far. Today, Friday, the resulting smog/vog is intense at ground level. This a major weather/public health crisis, occurring while Taal isn’t showing much change (still Level 1 alert). It’s late and to get started here I’ll just reference one Talkweather post and, below, share another, putting updates below that.
Uploaded about five hours ago, this Manila Bulletin video’s text quotes PHIVOLCS as saying this haze in the national capital is not from Taal, which I take to mean it is an inversion effect, while this report quotes the country’s weather specialists (PAGASA) noting some intrusion into Manila “air space” of Taal’s vog cloud — an interesting case of the volcanologists pointing to weather and the mets bringing in the volcano.
Of note, those hospitalizations and school closures, reported in the articles I saw, were in provinces around Taal (Batangas and Cavite), not Manila.
It seems to me that something like an inversion would work this way, with urban sources building smog over Manila and, in addition, the volcano vogging up its own neighborhood. (As mentioned, its degassing is only a little higher than usual right now, per PHIVOLCS.)
Here’s a currently livestream at Taal (in Filipino), looking out across the lake towards Volcano Island. (Visibility is very bad.)
The challenge is for people who, over decades, have internalized instructions for a volcanic emergency to become open now to a more complex hazard situation that also includes weather conditions.
Hope the smog/vog doesn’t last much longer.
September 23, 2023, 11:57 a.m., Pacific: Weather conditions changed, apparently.
This is one of the most info-laden, easy-to-digest intros I’ve read to date:
MANILA, Philippines — Air quality in Metro Manila and nearby provinces has returned to normal, as the pollution-related smog in the metropolis as well as the volcanic smog or vog from Taal Volcano have cleared, according to the Department of Environment and Natural Resources (DENR).
— Source
But other news yesterday also reported that people did sicken during the event; offices and courts in some areas were closed, as well as schools.
Meteorology and volcanology seem to be in separate categories for many in journalism, judging by the confusion they showed in covering this complex crisis.
To some extent that’s understandable: Taal is a Decade Volcano and can be very deadly.
But the weather can be dangerous and deadly, too.
And when they combine…
This all reminds me of the scene in Jurassic Park where the hunter is focused on one velociraptor and another sneaks up on him.
September 24, 2023, 2:11 p.m., Pacific: Per this report, at least 263 people in the Taal region have had health issues from its vog (I didn’t check what the smog did to Metro Manila residents’ health, but it certainly didn’t boost it.).
Anyway, the inversion is gone — for now.
It occurred during a relatively typical level of degassing at Taal. I hate to think of the number of people with health issues there would have been if Taal had been going through one of its five-digit SO2 emission phases.
As it well could have been.
[LAYPERSON SPECULATION] As I understand it, those occur whenever a new batch of magma trickles up from the depths and degasses through the underground hydrothermal field that presumably is capped and, I think, centered under or very close to Volcano Island.[/LAYPERSON SPECULATION]
Speaking of Volcano Island, here is video it posted by the same YouTuber yesterday, post inversion (I don’t know what he is saying):
September 24, 2023, 9:55 p.m., Pacific: Per PHIVOLCS about four hours ago:
And per this report, classes have been suspended in some places because of vog.
Marlon Abuyo streamed it a few hours ago, too – nowhere near the level on Friday but you can see it, and it’s probably harder to take today after that exposure:
September 26, 2024, 3:18 p.m., Pacific: Per this report:
Phivolcs on Tuesday said the volcanic smog or vog is no longer visible in the Taal region amid a minimal thermal inversion and a reduced emission of sulfur dioxide from the Taal Volcano.
Phivolcs Director Dr. Teresito Bacolcol said the threat of vog would remain as long as the volcano continues to spew sulfur dioxide…
Flight To Wonder 