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How much sulfur dioxide (SO2) gas does Kīlauea emit?

Kīlauea typically emits between 500 and 14,000 metric tons of sulfur dioxide gas (SO2) per day during periods of sustained eruption.

During the 2018 eruption at Kīlauea’s Lower East Rift Zone, SO2 emissions were over 100,000 metric tons per day, in keeping with the increased vigor of that eruption. Methods for calculating emission rates for SO2 can be complicated and challenging in the high-rate conditions that existed at that time. Extremely high SO2 levels can saturate instruments, and accurate wind speed--which is critical in calculations--is sometimes difficult to obtain.

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