Distribution of Sulfur Dioxide in the Troposphere of the Pacific Ocean

Airborne field programs such as the NASA PEM and TRACE-P missions and the NSF ACE missions provided an opportunity to make a large number of determinations of sulfur dioxide in the Pacific troposphere. These determinations were made over the latitude range 80 S to 80 N and from the surface to 12 km. Surface determinations will be reported for the South Pole. All determinations were obtained using isotopically labeled standards and either Gas Chromatography/Mass Spectrometry or Atmospheric Pressure Ionization Mass Spectrometry. Data for the mid and western North Pacific spanned the period 1991 to 2001. It documented a large flux of sulfur dioxide across the North Pacific. Other interesting observations include the importance of the sulfur dioxide emissions from volcanoes, a very low background sulfur dioxide level in the southern hemisphere, and the transport of sulfur dioxide from the stratosphere to the troposphere just after the eruption of Mt. Pinatubo.