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What is "vog"? How is it related to sulfur dioxide (SO2) emissions?

Vog (volcanic smog) is a visible haze comprised of gas and an aerosol of tiny particles and acidic droplets created when sulfur dioxide (SO2) and other gases emitted from a volcano chemically interact with sunlight and atmospheric oxygen, moisture, and dust. Volcanic gas emissions can pose environmental and health risks to nearby communities.  

Vog is a hazard that's associated with Hawaiian volcanoes in particular. See the Hawaii Interagency Vog Information Dashboard for detailed information and current conditions.

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