Spatial and Temporal Variations in SO<inf>2</inf> and PM<inf>2.5</inf> Levels Around Kīlauea Volcano, Hawai'i During 2007–2018

Among the hazards posed by volcanoes are the emissions of gases and particles that can affect air quality and damage agriculture and infrastructure. A recent intense episode of volcanic degassing associated with severe impacts on air quality accompanied the 2018 Lower East Rift Zone (LERZ) eruption of K¯ılauea volcano, Hawai‘i. This resulted in a major increase in gas emission rates with respect to usual emission values for this volcano, along with a shift in the source of the dominant plume to a populated area in the lower flank of the volcano. This led to reduced air quality in downwind communities. We analyse open-access data from the permanent air quality monitoring networks operated by the Hawai‘i Department of Health (HDOH) and National Park Service (NPS), and report on measurements of atmospheric sulfur dioxide (SO2) between 2007 - 2018 and PM2.5 (aerosol particulate matter with diameter