How much sulfur dioxide (SO2) gas does Kīlauea emit?
Based on recent (June 2008) measurements of gas emissions from the two currently active vents on Kīlauea—Pu`u `Ō `ō (east rift) and Halema`uma`u (summit)—the combined total ranges from 2,000 to 4,000 tonnes (on average) of SO2 emitted from the volcano each day. These gas emission rates are often affected by changes in magma supply, seismicity, and surface deformation of the volcano. Kīlauea has been erupting nearly continuously along its east rift zone since 1983. For most of those years, Pu`u `Ō `ō, the active east rift vent, has been emitting around 1,500-2,000 tonnes of SO2 daily. As seen in the graph below, occasional spikes in SO2 emissions from Pu`u `Ō `ō have exceeded 5,000 tonnes/day.
