Using atmospheric CCl4 as an internal reference in gas standard preparation

Supplementary material to "First simultaneous measurements of peroxyacetyl nitrate (PAN) and ozone at Nam Co in the central Tibetan Plateau: impacts from the PBL evolution and transport processes"

“…However, CCl 4 is believed to be well mixed to a large scale in clean area air due to sparse emission and long lifetime (42±12 years), thus its concentration at remote sites can be treated as constant in a short period (Simmonds et al, 1998). Based on this idea, Wang et al (2000) suggested the feasibility of using CCl 4 as an internal calibrator gas. The second assumption is prerequired for any 2 application of similar indirect calibration and normally applicable if the ECD sensitivity is stable with a GC run.…”