Pyrocumulus clouds aren’t particularly threatening – no more than normal thunderstorms, anyway. Just one of plenty of types of volcanic weather, you’re more likely to be threatened by volcanic fog, or vog. This mixture of carbon dioxide, water vapor, and sulfur dioxide – which readily reacts with water to form sulfuric acid droplets – tracks with how much sulfur dioxide is emerging from the fissures.
Unfortunately, since the geochemical change in Kilauea’s magma in the recent past, the Hawaiian Volcano Observatory has tracked a significant uptick in the effusion rate of sulfur dioxide. Although not immediately threatening, it can be hazardous if you’re overexposed to it, or if you have a pre-existing respiratory problem.
“Volcanic gas emissions remain very high from the fissure eruptions,” the latest USGS advisory notes. “If a forecast shift in wind direction occurs today, widespread vog could occur on the Island of Hawaii.” As ever, follow the advice of the authorities, and if possible, don’t breathe it in.
Sure, volcanic weather – like vog, and the acidic plumes of laze on the coast – serve as a reminder that the ongoing eruption at Kilauea is potentially dangerous. The risks don't change the fact that, on a purely aesthetic level, you just have to give Kilauea some respect: From lava fountains reaching heights of a 15-story building to creating its own goddam weather, what more could you ask for at this point?
Curious, I asked the USGS if there's any other type of volcanic weather out there.
“We're not sure...but we do know that volcanic eruptions can occasionally blow holes in existing weather,” they explained. “Back in the 1980s, when Pu’u ‘O’o would experience high fountains, it would stop raining in the vicinity of the fountain, and then start raining again when the fountain ceased.”
That's not all: as pointed out by volcanologist Dr Janine Krippner, you can also get lava-powered waterspouts.