QBO in WACCM4 (free running version)

[deepashree_dutta@student_unsw_edu_au]

Hi all,

I am using WACCM with CAM4 (compset - F1850W).

Can anyone please clarify how QBO is represented in the model.
(According to Marsh et al 2013 QBO is included in WACCM4; does it not work with the default PI component set?)
I looked at monthly mean zonal winds in the tropics (averaged between 5N-5S) at 50hPa and 10hPa, but the QBO signal is not clear.

Please let me know,
Thanks in advance!
Deepashree

 

[mmills]

The QBO is nudged in WACCM4. I recall that the QBO nudging is turned off for preindustrial (1850) compsets. If you create a case from a 20th Century WACCM4 compset, you will see the QBO nudging settings in the atmosphere namelist (CaseDocs/atm_in). You can copy those to the user_nl_cam file for your 1850 case to turn on QBO nudging.