Photos capturing massive cauliflower-shaped clouds have been surfacing on social media in the Vancouver area, believed to be pyrocumulus clouds formed by a wildfire over 200 kilometers away. The B.C. Wildfire Service reported that the Anderson Creek fire was detected during aircraft surveillance on Tuesday and rapidly intensified due to strong winds.
Meteorologist Matt Loney from Environment Canada explained that each fire produces significant heat, and the Anderson Creek fire seemed to have intensified substantially. Images shared on various social media platforms display towering cumulus clouds above dark smoke columns in the sky, visible as far as Coquitlam, approximately 220 kilometers away.
Loney elaborated that any source of intense heat leading to strong convection currents can trigger the formation of these clouds as hot air rises swiftly, causing moisture to condense. He drew an analogy by likening the process to opening a freezer door on a scorching summer day, where fog descends towards the ground due to temperature variations.
The clouds are laden with various particulates such as burning embers, dust, and ashes, making them visible to the naked eye. As the cloud reaches a certain warmth level, preventing it from ascending further, it disperses horizontally. The vertical growth of the cloud from the Boston Bar-area fire indicates not just the heat’s intensity but also the atmosphere’s instability, making it visible from multiple angles.
Rachel White, an assistant professor of atmospheric sciences at the University of British Columbia, expressed awe and concern over the photos of clouds from the Fraser Canyon. While she hasn’t personally witnessed these pyrocumulus clouds, she expressed curiosity from a scientific perspective and highlighted the daunting experience of witnessing the destructive force of wildfires.
White emphasized the alarming aspect that these clouds can trigger thunderstorms with lightning, potentially sparking more wildfires, underscoring the peril associated with such natural phenomena. She stressed the unpredictable nature of whether a cloud system will generate lightning, contingent on the specific conditions in that vicinity.