Ungrib cannot read surface CFSR data (UU/VV)

The surface CFSR data contains all required variables for Vtable.CFSR_sfc_flxf06, but when I run ./ungrib.exe it cannot read near surface wind speed (UU and VV) as following:

###############################################################################

Inventory for date = 2010-12-10 00:00:00

PRES TT RH SPECHUMD UU VV PSFC SM000010 SM010040 SM040100 SM100200 ST000010 ST010040 ST040100 ST100200 SEAICE LANDSEA SOILHGT SKINTEMP SNOW
-------------------------------------------------------------------------------
2001.0 X X X O O X X X X X X X X X X X X X X
-------------------------------------------------------------------------------

###############################################################################


The output of ./util/g2print.exe 201012100000.pgbh06.gdas.20101206-20101210.grb2 is

ungrib - grib edition num 2
reading from grib file = 201012100000.pgbh06.gdas.20101206-20101210.grb2
unknown model and orig center
---------------------------------------------------------------------------------------
rec Prod Cat Param Lvl Lvl Lvl Prod Name Time Fcst
num Disc num code one two Templ hour
---------------------------------------------------------------------------------------
1 0 0 0 1 0 0 0 TMP 2010-12-09_18:00:00 06
2 2 0 192 106 0 10 0 SOILW 2010-12-09_18:00:00 06
3 2 0 192 106 10 40 0 SOILW 2010-12-09_18:00:00 06
4 0 0 0 106 0 10 0 TMP 2010-12-09_18:00:00 06
5 0 0 0 106 10 40 0 TMP 2010-12-09_18:00:00 06
6 0 1 13 1 0 0 0 WEASD 2010-12-09_18:00:00 06
7 2 0 0 1 0 0 0 LAND 2010-12-09_18:00:00 06
8 10 2 0 1 0 0 0 ICEC 2010-12-09_18:00:00 06
10 0 2 2 103 10 0 0 UGRD 2010-12-09_18:00:00 06
10 0 2 3 103 10 0 0 VGRD 2010-12-09_18:00:00 06
11 0 0 0 103 2 0 0 TMP 2010-12-09_18:00:00 06
12 0 1 0 103 2 0 0 SPFH 2010-12-09_18:00:00 06
13 0 3 0 1 0 0 0 PRES 2010-12-09_18:00:00 06
14 2 0 192 106 40 100 0 SOILW 2010-12-09_18:00:00 06
15 2 0 192 106 100 200 0 SOILW 2010-12-09_18:00:00 06
16 0 0 0 106 40 100 0 TMP 2010-12-09_18:00:00 06
17 0 0 0 106 100 200 0 TMP 2010-12-09_18:00:00 06
18 0 3 5 1 0 0 0 HGT 2010-12-09_18:00:00 06


Successful completion of g2print


But when I download this surface it contains two files at each time step as:

1- pgbh06 file
201012100000.pgbh06.gdas.20101206-20101210.grb2

2- ipvh06 file
201012100000.ipvh06.gdas.20101206-20101210.grb2


Also, Vtable.CFSR_sfc_flxf06 is

GRIB1| Level| From | To | metgrid | metgrid | metgrid |GRIB2|GRIB2|GRIB2|GRIB2|
Param| Type |Level1|Level2| Name | Units | Description |Discp|Catgy|Param|Level|
-----+------+------+------+---------------+----------+----------------------------------------------------+-----------------------+
11 | 105 | 2 | | TT | K | Temperature at 2 m | 0 | 0 | 0 | 103 |
| 105 | 2 | | RH | % | Relative Humidity at 2 m | 0 | 1 | 1 | 103 |
51 | 105 | 2 | | SPECHUMD | kg kg-1 | | 0 | 1 | 0 | 103 |
33 | 105 | 10 | | UU | m s-1 | U at 10 m | 0 | 2 | 2 | 103 |
34 | 105 | 10 | | VV | m s-1 | V at 10 m | 0 | 2 | 3 | 103 |
1 | 1 | 0 | | PSFC | Pa | Surface Pressure | 0 | 3 | 0 | 1 |
144 | 112 | 0 | 10 | SM000010 | fraction | Soil Moist 0-10 cm below grn layer (Up) | 2 | 0 | 192 | 106 |
144 | 112 | 10 | 40 | SM010040 | fraction | Soil Moist 10-40 cm below grn layer | 2 | 0 | 192 | 106 |
144 | 112 | 40 | 100 | SM040100 | fraction | Soil Moist 40-100 cm below grn layer | 2 | 0 | 192 | 106 |
144 | 112 | 100 | 200 | SM100200 | fraction | Soil Moist 100-200 cm below gr layer | 2 | 0 | 192 | 106 |
11 | 112 | 0 | 10 | ST000010 | K | T 0-10 cm below ground layer (Upper) | 0 | 0 | 0 | 106 |
11 | 112 | 10 | 40 | ST010040 | K | T 10-40 cm below ground layer (Upper) | 0 | 0 | 0 | 106 |
11 | 112 | 40 | 100 | ST040100 | K | T 40-100 cm below ground layer (Upper) | 0 | 0 | 0 | 106 |
11 | 112 | 100 | 200 | ST100200 | K | T 100-200 cm below ground layer (Bottom)| 0 | 0 | 0 | 106 |
91 | 1 | 0 | | SEAICE | proprtn | Ice flag | 10 | 2 | 0 | 1 |
81 | 1 | 0 | | LANDSEA | proprtn | Land/Sea flag (1=land, 0 or 2=sea) | 2 | 0 | 0 | 1 |
7 | 1 | 0 | | SOILHGT | m | Terrain field of source analysis | 0 | 3 | 5 | 1 |
11 | 1 | 0 | | SKINTEMP | K | Skin temperature (can use for SST also) | 0 | 0 | 0 | 1 |
65 | 1 | 0 | | SNOW | kg m-2 | Water equivalent snow depth | 0 | 1 | 13 | 1 |
-----+------+------+------+---------------+-----------+---------------------------------------------------+-----------------------+


How can I solve this problem

Thanks

Instead of the 'ipvh06' files, which may contain fields on isentropic levels, I think you may need to download the 'flxf06' files for surface data. Could you try again using the 'flxf06' and 'pgbh06' files?

These files are automatically selected when i choose in Parameter Selection: "WRF Model input : Vtable.CFSR - Surface" at RDA dataset from 093.2 (CFSR v1) or ds094.0 (CFSR v2), so how can I download 'flxf06' and 'pgbh06' files?

I don't often use RDA's web interface, but it may depend on exactly which selections you make. Can you try the following (which seems to work for me):

1) Go to the "Data access" tab for the 093.0 (CFSR) dataset: https://rda.ucar.edu/datasets/ds093.0/#!access
2) Choose "Web File Listing" under "Data File Downloads"
3) Choose "Faceted Browse"
4) Set the date range to 2010-12-06 0000 through 2010-12-06 0000
4) Select "WRF Model Input: Vtable.CFSR - Surface"
5) At the bottom of the page, click on "Continue"

When I try the above, I get a link to download a file named flxf06.gdas.20101201-20101205.tar .

Your steps are correct to obtain flxf files only for Grid: 0.312º x ~0.312º.
But when I change Grid to 0.5º x 0.5º the files of pgbh06 and ipvh06 appear again.
I change the Grid to 0.5º x 0.5º because the pressure levels data not available at 0.312º x 0.312º, and to make the input surface data are similar to pressure level data.

So, why the files changed when we change the Grid to 0.5º or how can I obtain on flxf files for 0.5º x 0.5º.
If I run WPS using surface data of 0.312º grids and pressure levels with 0.5º grids is this correct or there is a problem in the run.


On the other hand, when I downloaded the flxf files also UU and VV variables not read successfully by ungrib.exe the problem still exists , where the results are:

###############################################################################

Inventory for date = 2010-12-13 18:00:00

PRES TT RH SPECHUMD UU VV PSFC SM000010 SM010040 SM040100 SM100200 ST000010 ST010040 ST040100 ST100200 SEAICE LANDSEA SOILHGT SKINTEMP SNOW
-------------------------------------------------------------------------------
2001.0 X X X O O X X X X X X X X X X X X X X
-------------------------------------------------------------------------------
Name of source model =>NCAR

###############################################################################


Thanks

The question of why the RDA is returning links to ipvh06 files is probably best directed to the RDA support people. You can find their e-mail address under the "About/Contact" tab on the main RDA web site.

In general, there should be no problem to mix 0.312x0.312 Gaussian grid surface fields with 0.5x0.5 upper-air fields, though.

Also the problem still exists, when I downloaded the flxf files the UU and VV variables not read successfully by ungrib.exe , where the results are:

###############################################################################

Inventory for date = 2010-12-13 18:00:00

PRES TT RH SPECHUMD UU VV PSFC SM000010 SM010040 SM040100 SM100200 ST000010 ST010040 ST040100 ST100200 SEAICE LANDSEA SOILHGT SKINTEMP SNOW
-------------------------------------------------------------------------------
2001.0 X X X O O X X X X X X X X X X X X X X
-------------------------------------------------------------------------------
Name of source model =>NCAR

###############################################################################

The problem here in ungrib.exe, because it cannot read the near surface UU and VV from CFSR flxf files, then it will interpolate them from the closest pressure level, that is not accurate.

Thanks

I'll see if I can reproduce this behavior in ungrib.exe myself.When you run ungrib.exe, are you processing just the flxf06 files, or both flxf06 and pgbh06 files? I.e., when running link_grib.exe, which files have been linked to GRIBFILE.AAA, GRIBFILE.AAB, etc.?
When running ungrib.exe, are you processing just 2010-12-13 18:00:00, or is there a range of times that are being processed?
Also, which version of the WPS are you using?

When I download the surface CFSR using Grid 0.312 x 0.312 only the flxf06 files are available to download, So when I run ungrib.exe, I process just the flxf06 files.
The pgbh06 appear with ipvh06 files when I select 0.5 x 0.5 CFSR from website.
All of these data give the same problem.

When running ungrib.exe, I process a range of times from 2010-12-09 00:00:00 to 2010-12-14 00:00:00

Also, the used version of the WPS is WPSV3.8.1

Thanks