The emission of volcanic gases, including sulfur dioxide and hydrogen sulfide, i

The emission of volcanic gases, including sulfur dioxide and hydrogen sulfide, is not unusual at the summit of Kīlauea. However, sulfur dioxide gas emission rates are now lower than they have been since before 1983, with about 50 tonnes/day measured at the summit of the volcano on the day of this photo (October 24). Even with low emissions, enough gas reaches the surface to produce yellow deposits of native sulfur on the crater walls, as seen here.