Scheduled Downtime
On Friday 21 April 2023 @ 5pm MT, this website will be down for maintenance and expected to return online the morning of 24 April 2023 at the latest

Hydrostatic & non-hydrostatic WRF runs, Hydrostatic & non-hydrostatic pressure level output types

This post was from a previous version of the WRF&MPAS-A Support Forum. New replies have been disabled and if you have follow up questions related to this post, then please start a new thread from the forum home page.


New member

I have a question about hydrostatic (denoted H henceforth) and non-hydrostatic (denoted NH henceforth) WRF run-time option ("non_hydrostatic" option within "&dynamics" options within "namelist.input" file) and H and NH pressure level output pressure type ("use_tot_or_hyd_p" option within "&diags" options within "namelist.input" file):

When I set WRF to run hydrostatitically ("non_hydrostatic" option above set to false), the output data on pressure levels (files "wrfplev3d_d<domain>_<date>.nc" or something like that) are different when using H or NH pressure level output pressure types. As the case is ran hydrostatically, isn't the pressure in the model hydrostatic and shouldn't using NH and H pressure level output pressure types ("use_tot_or_hyd_p" being 1 or 2, respectively) give same pressure-level data?

Depending on the answer to the question above, it would be interesting to know how exactly WRF calculates the hydrostatic pressure when doing pressure-level outputs and if this is different than the hydrostatic pressure inside WRF model. For example does WRF use hydrostatic pressure or dry hydrostatic pressure when doing these calculations internally and/or externally?

Thanks so much for your help in advace.

Best Regards,