Remember this from last year?
Taal, near the Philippines’ capital city of Manila, grabbed world headlines when it had this spectacular eruption in January 2020. Well, it’s rumbling again, thus far without violence.
It’s a good time to share an update of the Taal chapter in my Decade Volcanoes eBook (on sale this month; see details at end of post.)
This huge Philippine volcano, just thirty miles south of Manila, doesn’t fit the “big pointy mountain” stereotype.
It’s a caldera — basically a 9 x 12-mile-wide hole in the island of Luzon.
A series of enormous prehistoric eruptions excavated it over many millennia. The last of these, according to Reyes (see references), occurred some 5,500 to 7,000 years ago.
Taal does have what appears to be volcano that sits in the middle of a vast lake.
During the eruption in January 2020, a few news reports erroneously called this “Taal Volcano.”
But looks are deceiving.
Volcano Island — yes, that’s its name — rises out of the crater lake that fills most of Taal’s gaping maw.
It is a built-up complex of vents and other topographic features that formed during relatively small steam explosions.
Taal Caldera is much larger than Volcano Island.
The ridges and hills around that big lake are part of the caldera rim.
Like the 2020 blast, most historical eruptions at Taal have happened on Volcano Island.
However, the island’s forty-some vents are supplemented by others that have opened up underwater on the caldera floor.
In quiet times, this is a scenic, productive area.
Tourism, fishing, farming, forestry, services, cottage industries, and manufacturing make Batangas Province very successful.
However, everyone knows there is risk.
Taal is the country’s second most active volcano. It has destroyed many local communities down through the centuries and claimed an estimated 6,000 lives. (Reyes; Oregon State; Wikipedia)
Through the Decade Volcano program, experts realized “the remarkable extent in which water is involved in eruptions of Taal Volcano” and now know that this can extend the reach of eruptions here into heavily populated regions. (Newhall)
This was published in September 2020, and shows the island still decked in ash from January’s eruption. As well, you get a feeling for just how closely Taal Caldera and the local communities are intertwined through livelihood (the fishing nets, for example), infrastructure, and recreation. This is something found at many Decade Volcanoes.
Needless to say, the ongoing unrest in March 2021 makes millions of Taal’s human neighbors very uneasy.
14.002° N, 120.993° E, in Batangas Province on southwestern Luzon, the Philippines. The GVP Volcano Number is 273070.
Per the Global Volcanism Program website:
- Within 5 km (3 miles): 717,090.
- Within 10 km (6 miles): 717,090.
- Within 30 km (19 miles): 2,380,326.
- Within 100 km (62 miles): 24,814,047.
Those are official numbers. In addition, an estimated 5,000 people lived on Volcano Island in 2016, even though the island is designated as a Permanent Danger Zone, for obvious reasons, and has no services. (Reyes)
As of October 20, 2020, the alert level is 1: low-level unrest, but no eruption imminent.
The most recent PHIVOLCS bulletin as of time of writing (March 20, 2021, Philippines time):
In the past 24-hour period, the Taal Volcano Network recorded one hundred and seventy-five (175) volcanic earthquakes, including one hundred and thirty-one (131) episodes of volcanic tremor having durations of one (1) to fifteen (15) minutes. Activity at the Main Crater consisted of moderate emission of steam-laden plumes from fumarolic vents that rose 80 to 100 meters high. Sulfur dioxide (SO2) emission that averaged 603 tonnes/day was measured yesterday, 19 March 2021. Temperature highs of 71.8°C and pH of 1.59 were last measured from the Main Crater Lake respectively on 04 March and 12 February 2021. Ground deformation parameters from electronic tilt, continuous GPS and InSAR data analysis indicated a very slow and steady inflation and expansion of the Taal region since after the January 2020 eruption. These parameters may indicate increased magmatic activity at shallow depths beneath the edifice.
Alert Level 2 (Increased Unrest) is maintained over Taal Volcano.
- Eruption styles: Phreatic (steam) or phreatomagmatic (water and molten rock interacting) explosions like the one in January 2020. As well, Taal sometimes has Strombolian activity (lava fountaining and gassy “burps”) and Plinian eruptions.
- Biggest recorded event: In 1754, the main crater on Volcano Island unexpectedly erupted in mid-May and kept at it until early December. Intensity estimates based on old documents range from VEI 3 to VEI 5, possibly even higher. Residents of Manila had to use artificial light during the day, while Taal’s eruption column may have been as high as 25 miles at times. Pyroclastic flows and base surges laid down thick deposits and caused huge waves that washed away whatever lakeside towns weren’t already buried underneath ash. This is the “worst-case” event that today’s emergency managers base their plans on. (Reyes)
- Most recent eruption: January 12, 2020, as of the time of writing this post.
- Past history: See the GVP for details. At least four of Taal’s 33 historical eruptions have been violent (VEI 3 TO VEI 5): these occurred in 1749, 1754, 1911, and 1965.
The Philippines Institute of Volcanology and Seismology (PHIVOLCS). Here is their Taal bulletin page.
Darwin Volcanic Ash Centre (VAAC) issues advisories to aircraft when needed.
This is a chapter from my eBook “The Decade Volcanoes and Us,” which is on sale for only $3.50 through April 5th at Google Play and other online stores (not Amazon, unfortunately: you have to give them sole distribution rights in order to run a sale).
Featured image: etrhamjr via Wikimedia, CC BY-SA 4.0.
Global Volcanism Program. 2020. Taal. https://volcano.si.edu/volcano.cfm?vn=273070 Last accessed March 19, 2020.
Newhall, C. 1996. IAVCEI/International Council of Scientific Union’s Decade Volcano projects: Reducing volcanic disaster. status report. US Geological Survey, Washington, DC. Retrieved from https://web.archive.org/web/20041115133227/http://www.iavcei.org/decade.htm
Oregon State University: Volcano World. 2020. Taal. http://volcano.oregonstate.edu/taal Last accessed March 19, 2020.
Reyes, P. J. D. 2019. An interdisciplinary study of the hazards associated with an AD1754 style eruption of Taal Volcano, Philippines. University of Sydney, doctoral thesis.
Wikipedia. 2020. Taal Volcano. https://en.wikipedia.org/wiki/Taal_Volcano Last accessed March 19, 2010.