[Met_help] [rt.rap.ucar.edu #57604] History for wind rotation in MET

[Paul Oldenburg via RT]

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  Initial Request
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Dear met_help,

In WRF ARW output, wind are rotated based on the map projection, like 
Lambert conformal projection and so on. I am writing to ask whether MET 
rotate model grid relative wind to earth relative wind?
If yes, and how to make sure it has been done from standard output or 
some marks in data?

Best wishes
Yujie Pan


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  Complete Ticket History
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Subject: Re: [rt.rap.ucar.edu #57604] wind rotation in MET
From: Paul Oldenburg
Time: Thu Jul 26 13:03:15 2012

Yujie,

Depending on which MET tool you are using, setting the verbosity high
enough should result in messages printed to
standard output that indicate if and how the winds in the input files
are rotated.  For example, the grid_stat tool
prints a message like this with the -v 3 option set:

DEBUG 3: MetGrib2DataFile::check_uv_rotation() - Found pair match
"VGRD/Z10" in GRIB2 record 10 field 1
DEBUG 3: Rotating U and V wind components from grid-relative to earth-
relative.
DEBUG 3: MetGrib2DataFile::data_plane_array() - Found exact match for
"WIND/Z10" in GRIB2 record 10 field 1 of GRIB2
file "nam_2012040900_F012_gRtma.grib2"

At this time, there is no way to control the wind rotation, it is
automatically triggered by detecting the wind-related
fields like UGRD and VGRD.  Also, wind rotation is only performed on
data that is read from GRIB and GRIB2 data files at
this time.  Does this answer your questions?  If not, please let me
know.

Paul


On 07/26/2012 12:13 PM, Yujie Pan via RT wrote:
>
> Thu Jul 26 12:13:34 2012: Request 57604 was acted upon.
> Transaction: Ticket created by yjpan at ou.edu
>         Queue: met_help
>       Subject: wind rotation in MET
>         Owner: Nobody
>    Requestors: yjpan at ou.edu
>        Status: new
>   Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=57604 >
>
>
> Dear met_help,
>
> In WRF ARW output, wind are rotated based on the map projection,
like
> Lambert conformal projection and so on. I am writing to ask whether
MET
> rotate model grid relative wind to earth relative wind?
> If yes, and how to make sure it has been done from standard output
or
> some marks in data?
>
> Best wishes
> Yujie Pan
>


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Subject: Re: [rt.rap.ucar.edu #57604] wind rotation in MET
From: Yujie Pan
Time: Thu Jul 26 13:07:21 2012

Paul,

Thank you so much! The rotation information is found with -v option.

Have a good day!
Yujie

On 7/26/2012 2:03 PM, Paul Oldenburg via RT wrote:
> Yujie,
>
> Depending on which MET tool you are using, setting the verbosity
high enough should result in messages printed to
> standard output that indicate if and how the winds in the input
files are rotated.  For example, the grid_stat tool
> prints a message like this with the -v 3 option set:
>
> DEBUG 3: MetGrib2DataFile::check_uv_rotation() - Found pair match
"VGRD/Z10" in GRIB2 record 10 field 1
> DEBUG 3: Rotating U and V wind components from grid-relative to
earth-relative.
> DEBUG 3: MetGrib2DataFile::data_plane_array() - Found exact match
for "WIND/Z10" in GRIB2 record 10 field 1 of GRIB2
> file "nam_2012040900_F012_gRtma.grib2"
>
> At this time, there is no way to control the wind rotation, it is
automatically triggered by detecting the wind-related
> fields like UGRD and VGRD.  Also, wind rotation is only performed on
data that is read from GRIB and GRIB2 data files at
> this time.  Does this answer your questions?  If not, please let me
know.
>
> Paul
>
>
> On 07/26/2012 12:13 PM, Yujie Pan via RT wrote:
>> Thu Jul 26 12:13:34 2012: Request 57604 was acted upon.
>> Transaction: Ticket created by yjpan at ou.edu
>>          Queue: met_help
>>        Subject: wind rotation in MET
>>          Owner: Nobody
>>     Requestors: yjpan at ou.edu
>>         Status: new
>>    Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=57604 >
>>
>>
>> Dear met_help,
>>
>> In WRF ARW output, wind are rotated based on the map projection,
like
>> Lambert conformal projection and so on. I am writing to ask whether
MET
>> rotate model grid relative wind to earth relative wind?
>> If yes, and how to make sure it has been done from standard output
or
>> some marks in data?
>>
>> Best wishes
>> Yujie Pan
>>
>


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