‘Sulfur dioxide haze’ in Cebu? Pagasa-Mactan says there’s none

LOOK: A day after the eruption of Kanlaon Volcano, nearby residents harvest their crops and vegetables to prevent the destruction that may result from the ashfall. | via Ferdinand Edralin / AFP

CEBU CITY, Philippines – No need to panic.

While the presence of sulfur dioxide has been detected in several areas in the Visayas following Mount Kanlaon’s eruption, the air here remained safe for breathing.

The state weather bureau made this clarification after reports of dangerous levels of sulfur dioxide and sulfur dioxide haze in Cebu went viral.

READ MORE:

 After Kanlaon eruption, no ash fall, sulfur dioxide flux expected in Cebu

DSWD distributes P750,000 worth of aid to Kanlaon eruption victims

Kanlaon Volcano update: 53 quakes recorded; Alert Level 2 stays

Sulfur dioxide is expected in the air after volcanic eruptions, the Philippine Atmospheric Geophysical and Astronomical Services Administration in Mactan (Pagasa-Mactan) said on Wednesday, June 5.

But in Cebu, its concentration on the surface level has not reached dangerous levels, said Joseph Merlas, weather specialist at Pagasa-Mactan.

Furthermore, the cloudy skies Cebu experienced since Monday were due to localized thunderstorms and not because of ‘sulfur dioxide haze.’

“Good news sad kay generally fair weather man ta so walay kusog nga hangin unya ang hangin nato kay sa southwest and southeast so palayo siya sa Cebu City area,” Merlas said.

Two days after the eruption of Mount Kanlaon, photos of what looked like thick concentrations of sulfur dioxide over Visayas and Mindanao went viral on social media.

The images were captured from an open-access weather monitoring tool, and showed a deep, red formation hovering over the Visayas and Mindanao on June 4 and June 5.

According to Merlas, meteorological monitoring platforms have nuances in presenting real-time data or information. This means that should they be shared without proper consultation from experts, these may only mislead the public.

In the case of sulfur dioxide’s presence in Cebu, the photos likely showed the total concentration of sulfur dioxide in all levels of the atmosphere.

The atmosphere has at least five levels.

“Naa tay makita nga baga nga sulfur dioxide medyo hadlok sa nagtan-aw but (kaning mga weather monitoring tools) total column or concentration (sa sulfur dioxide) of the atmosphere ilahang ipakita. Not necessarily sa surface,” explained Merlas.

On the other hand, Pagasa-Mactan, which also covered the entire Visayas, strongly advised residents near Kanlaon to wear masks and stay indoors as concentration of sulfur dioxide is stronger in these areas.

Outside Negros, like in Cebu, they told those with respiratory problems and co-morbidities to do the same.

Sulfur dioxide

Since its phreatic eruption last June 3, Kanlaon has been emitting hundreds of tons of sulfur dioxide – a colorless gas pollutant – into the air every day.

The highest recorded was 4,113 tonnes, based on the latest advisory from the Philippine Institute of Volcanology and Seismology (Phivolcs).

Exposure to high levels of sulfur dioxide can lead to harmful effects on the lungs, according to the American Lung Association. Symptoms may include wheezing, shortness of breath and chest tightness.