Soils are an important source and sink of carbon.  Understanding the contribution of soil organic carbon (SOC) to the global carbon cycle can help researchers improve models of global climate change.  In 1993 and 1995 the authors published estimates of global soil carbon stocks.  This study provides an update to the earlier estimates by utilizing a newly revised global soil regions map and a larger pedon database.   Soil organic carbon was calculated to three depths, 0-25, 0-50 and 0-100 cm.  Mean carbon values are calculated by soil suborder.  The dominant soil suborders for each map unit of the global soil regions map are assigned a mean carbon value from the pedon database.  Maps for each of the three depths and tables of areas by soil suborder are presented.  The new estimates show that there are 739 Pg to 25cm depth, 1,052 Pg to 50cm depth and 1,285 Pg to one meter depth of organic carbon stored in global soils.  Together, Gelisols and Histosols occupy 10 percent of Earth's ice-free land area and store 30 percent of the entire stock of SOC.