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

(RESOLVED) Questions regarding Vtable.ECMWF_sigma and its variables

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.

MartinHagman

New member
Hi,

I have attached the Vtable.ECMWF_sigma. Now I wonder why, for example, DEWPOINT has GRIB code 168, but RH below has no variable number? Furthermore DEWPOINT has no description in the last column. Why is that?

The same way is happening with SNOW_EC and SNOW. The latter has no GRIB code in the Vtable. Why?

If I look into the intermediate file I, for example, find RH at level 200100, but not DEWPOINT....

Is there a rule for writing the Vtable like this? I mean, is there a connection between that the DEWPOINT has a GRIB code, and RH not, when we, although, find the latter in the intermediate file?

I also want to initialize WRF with QCLOUD and QICE from ECMWF. How do I add these to the Vtable?

Thank you very much for your help! :)

Best,
Martin Hagman
 

Attachments

  • Skärmavbild 2019-02-11 kl. 22.57.34.png
    Skärmavbild 2019-02-11 kl. 22.57.34.png
    365 KB · Views: 558
Hi Martin,

This is because the datafile doesn't include variable 'RH' at 2m height, but it has 2m dewpoint. Thus ungrib will extract 2m dewpoint, then derive 2m RH from it. The same for SNOW_EC and SNOW.

To add QICE and QCLOUD, you need to find the GRIB parameters for these variables, then add them to Vtable. WRF User Guide has a brief description how to modify Vtable. Hope it could be helpful for you. Please see:

http://www2.mmm.ucar.edu/wrf/users/docs/user_guide_v4/v4.0/users_guide_chap3.html#_Creating_and_Editing_1
 
Top