An Air Quality Advisory went into effect for Grand Forks and surrounding areas Tuesday, Nov. 23, according to the Interior Health Authority and B.C.’s environment ministry. Cold weather and smoke from wood-burning stoves are believed to have raised airborne fine particulate matter (FPM) above healthy levels, ministry meteorologist Trina Orchard told The Gazette.
People with underlying health conditions — especially respiratory ailments like asthma, Chronic Obstructive Pulmonary Disease (COPD) and COVID-19 — should avoid vigorous activity until the advisory is lifted, likely after current weather conditions change.
Air Quality Advisories are triggered when FPM levels exceed Victoria’s daily objective of 25 micrometres per cubic metre (µg/m3), averaged over 24 hours. Those levels hit 27 µg/m3 as of 8 a.m. Tuesday.
Orchard attributed Tuesday’s FPM buildup largely to a weather phenomenon known as a temperature immersion, where a mass of cold, stagnant air hugs the ground, socking in smoke and other sources of FPM like industrial emissions and automotive exhaust.
The same cold temperatures are likely prompting people to heat their homes using wood-burning stoves, the smoke from which will likely hang in the air until the weather changes.
“I looked at the weather conditions for Grand Forks, and it looks like the city’s headed for a relatively snowy, rainy week. So, it would seem that the PM levels will persist for a few days,” Orchard explained.
Grand Forks and Castlegar had the highest FPM levels in B.C. in 2020, according to the BC Lung Association’s State of the Air Report, published this September.