Cartoon illustrating the global pattern of carbon degassing. Units are millions of tons of C/yr. Discharge of CO2 from submarine volcanoes remains unmeasured. Figure based on a schematic line drawing in Sano Y, Williams SN, Fluxes of mantle and subducted carbon along convergent plate boundaries, GEOPHYSICAL RESEARCH LETTERS 23 (20): 2749-2752 OCT 1 1996. Image courtesy of New Zealand American Submarine Ring of Fire 2007 Exploration, NOAA Vents Program, the Institute of Geological & Nuclear Sciences and NOAA-OE.