MANILA, Philippines – For the second time in five days, state volcanologists warned of an increase in sulfur dioxide (SO2) emission from Taal Volcano in the province of Batangas.

In an advisory issued at 11:30 pm on Sunday, August 7, the Philippine Institute of Volcanology and Seismology (Phivolcs) said 17,141 tons per day of SO2 were recorded on Sunday morning.

That is a new high since Taal was downgraded to Alert Level 1 on July 11, surpassing the 12,125 tons per day of SO2 last Wednesday morning, August 3.

Since July 15, SO2 emission has averaged 6,041 tons per day, higher than the average of 1,289 tons per day recorded between May and mid-July.

SO2 is a major gas component of magma.

Phivolcs added that upwelling in the Main Crater Lake and “voluminous” steam-rich plumes continue to be seen. Upwelling refers to the rising of volcanic fluids.

There were also 3 tremors lasting 9 minutes in the latest observation period.

So far, Taal Volcano is still under Alert Level 1. If increased volcanic activity persists, it might be raised back to Alert Level 2.

Under Alert Level 1, these are possible:

• sudden steam-driven or phreatic explosions
• volcanic earthquakes
• minor ashfall
• lethal accumulations or expulsions of volcanic gas

Given the risks, Taal Volcano Island should remain off-limits, Phivolcs said. – Rappler.com