Mean age-of-air in the stratosphere

Data production

Age-of-air is calculated in the EMAC model from a passive tracer with linearly increasing mixing ratio specified at the surface. To calculate age-of-air relative to the tropical tropopause, the average age at 10°N-10°S at the tropopause is subtracted. The simulation analyzed here is branched from a free‐running hindcast run, ensuring that the tracer field is fully spun up at the start of the period considered (Jöckel et al. 2016, RC1SD-base-10). Dynamics are specified with Newtonian relaxation, i.e. nudging, up to 10~hPa with ERA-Interim (Dee et al. 2011).

Post processing

The final data product includes post processing of transient data that is available at each grid box of the EMAC model with 90 vertical levels up to 80 km altitude ~0.01 hPa) and a ~2.8°x2.8° horizontal resolution. The age data was averaged over multiple years (2010-2013) and limited to stratospheric regions. 

Condition of use

The work is licensed under Creative Commons Attribution 4.0 International. We further kindly ask to credit the creators by citing the following publication analysing the data set: https://doi.org/10.21203/rs.3.rs-9087641/v1