Mean age of air anomaly derived from ACE-FTS N2O

The deseasonalized mean age of air (AoA) anomaly is derived using N2O observations from ACE-FTS and simulations of N2O and AoA from CLaMS. Results are provided as a monthly zonal mean in 10 degree latitude bins and on 19 pressure levels ranging from 100 hPa to 3.162 hPa. Four different versions of the AoA are provided, each using CLaMS simulations that were forced with a different reanalysis (ERA5, MERRA-2, JRA-55, ERA-Interim). AoA based on ERA5 is available from 2004/2 to 2021/12. AoA based on the other reanalyses is available from 2004/2 to 2017/12.