Sulfur Dioxide gas emissions from Mount St. Helens

SO2 gas emissions from the 1980 eruption of MSH through to 1988, and at the end of the graph are the October 2004 eruption emissions for comparison. The second graph shows a more detailed view of SO2 gas emissions from October 2005 to February 2008. Gas emissions declined toward the end of the eruption to very low levels that dip into the range of uncertainty. The grey shading surrounding the red line indicates the level of general uncertainty in the measurements.