Secondary-Organic-Carbon

Elemental carbon (EC) tracer method for estimating secondary organic carbon (OC) from measurements of total OC and EC. Primary OC is estimated as combustion-related OC (proportional to EC via the OC-to-EC ratio) plus noncombustion OC; secondary OC is the non-negative remainder. From Seinfeld and Pandis (2006), Chapter 14, Section 14.3.2, Equations 14.3–14.4.