New studies help refine Kīlauea gas emission rates

Kīlauea's summit plume—now you see it, now you don't. Top: Prior to the beginning of the 2008 Halema‘uma‘u eruption, Kīlauea's summit released a relatively transparent plume containing irritating but colorless SO2 gas. Bottom: Since the summit eruption began on March 19, 2008, the plume has carried much more SO2 from Halema‘uma‘u, along with a dense mixture of acidic particles that further degraded air quality, especially in the southern portion of Kīlauea's caldera, and has complicated gas measurements. In these paired east-looking views, the Halema‘uma‘u Crater parking lot sign appears on the right-hand side of the road. USGS photos.