Haze in Metro Manila caused by vog — DENR

MANILA, Philippines — Amid the haze in Metro Manila yesterday, the Department of Environment and Natural Resources (DENR) said many areas registered “very unhealthy” air quality, citing an Environmental Management Bureau (EMB) report that said the haziness in the metropolis was caused by the vog from Taal Volcano.

“For National Capital Region, the station in Makati City recorded an air quality index (AQI) of very unhealthy for ground-level upwind particulate matter (PM2.5), while stations in Caloocan, Pateros and Parañaque City recorded an air quality index of unhealthy for sensitive groups,” the DENR said.

It also said that the current air pollution levels may be primarily attributed to emissions from heavy vehicular traffic, especially during rush hour, and the effect of thermal inversion which traps air pollutants in the surface level.

“Haziness, on the other hand, may be attributed to the vog from the plume of Taal Volcano. Air quality varies in time and place and can change anytime depending on pollution sources and meteorological factors,” the DENR added.

Based on the EMB monitoring, the SM Skyranch station and Batangas State University station recorded a very unhealthy air quality index. Because of this, the DENR advised residents located in areas with very unhealthy air quality index to avoid heavy traffic areas.

“People with heart or respiratory diseases such as asthma should stay indoors as much as possible. Unnecessary trips should be postponed and people should voluntarily restrict usage of vehicles,” the DENR said.

It added that the EMB has observed from the nearest Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) station, located approximately 33.30 kilometers from Taal Volcano, that the surface wind direction is blowing from the southeast, which is away from Metro Manila.

“Thermal inversion was observed in the nearest PAGASA station at 3.0 km to 3.2 km elevation,” the EMB said.

The EMB monitoring also reported that the stations in Pateros and Taguig City recorded fair air quality index while those in Caloocan, San Juan, Makati and Parañaque cities recorded good air quality index.

The DENR has set the air quality of 0 to 50 µg/Ncm as good; 51 to 100 µg/Ncm as fair; 101 to 150 µg/Ncm as unhealthy; 151 to 200 µg/Ncm as very unhealthy; 201 to 300 µg/Ncm as acutely unhealthy and 301 to 500 µg/Ncm as emergency.?On Sept. 22, 2023, smog was experienced in Metro Manila as DENR had blamed the volume of vehicles in the streets for the haze. During that time, the AQI reached as high as 217 points in Parañaque City, 141 points in Pateros and 128 points in Makati.