An update on the QBO dataset to support the IGAC/SPARC CCMI Reference Simulations can be downloaded (zip archive). qbo_data_update.zip
The QBO dataset of the Freie Universität Berlin is used as input to a procedure where the data is interpolated to a consistent vertical grid (14 pressure levels from 90 to 10 hPa) and then extrapolated downward to 100 hPa and upward to 3 hPa.
The software to extent the QBO data vertically is written by Marco A. Giorgetta (Max Planck Institute for Meteorology, Hamburg Email: firstname.lastname@example.org).
All further information about the method can be found on the CCMVal2 webpage for the QBO(login required) and CCMVal1 webpage for the QBO.