Atmospheric Histories (1765-2022) for CFC-11, CFC-12, CFC-113, CCl4, SF6 and N2O (NCEI Accession 0164584)

It has been several years since Bullister (2015) prepared tables and figures of the annual mean tropospheric concentrations in the northern (NH) and southern (SH) hemispheres for the trace gases: CFC-11, CFC-12, CFC-113, carbon tetrachloride (CCl4), sulfur hexafluoride (SF6), and nitrous oxide (N2O). This is the first of periodic updates to the tables and figures compiled following similar methods with updated measurements from the community of scientists who monitor the global distributions of these compounds in the troposphere.

The datafile, Tracer_atmospheric_histories_revised_2023_Table1.csv, and Table 1 list the annual mean tropospheric concentrations of CFC-11, CFC-12, CFC-113, CCl4, SF6, and N2O in the northern and southern hemispheres (NH, SH) from 1765.5 to 2022.5. The reported values are the annual (Jan-Dec) mean mole fraction of these gases in dry air. Concentrations are in parts per trillion (ppt) for CFC-11, CFC-12, CFC-113, CCl4, and SF6; and in parts per billion (ppb) for N2O.